LSR 2-1's

No 1950's megaphones, No Aluminum Butt Plugs

Bonneville, Dyno, & Track Proven:  No Stupid Megaphones

If you want to make power on a multi-cylinder engine you have to use a collector system. Whether it's a V-Twin or a V-8 it's the same, and no less an authority than the famed engine builder Smokey Yunick will tell you that. Not using free exhaust energy to help your engine breathe is downright criminal.

No matter what the conventional wisdom is, staggered duals on a Harley will not make more power. You simply cannot escape the fact that a properly designed 2-1 will give you more useable torque where you need it, in the 2000 to 4000 rpm range, which means less downshifts and less rpm to get the job done.

A set of short staggered duals at peak rpm can be made to produce good power but they will be dead on their ass until they get there, whereas an engine developed around an LSR 2-1 exhaust can be made to perform from the bottom up with no dips in the torque band!

Pictured above is our LSR 2-1, 1 3/4", C Style, turnout part number 00-1167 with optional 45 Degree rotation.. Twin Cam 88, 95 cubic inch. Simply works.

Custom Made for Your Application...Grey Button to Your Application

From Sportsters to Top Fuel bikes we make the widest range of performance exhausts with options on primary tube size, tail section design and orientation, and even in special lengths and offsets to accomodate your specific requirements: FXR, Dyna, Softail, FLH/T Dressers, Road Kings, Road Glides, Shovelheads, Custom Chassis, Confederates, Bourgets, Indians, Supercharged applications, S.T.D. heads, S&S SA heads, S&S SA B2 heads....Check out the range of LSR 2-1 Exhaust Systems.

Note: All LSR 2-1 systems have welded-in non-removeable baffles

2-1 Designs are the best way to make power and torque. If you don't believe this then why is it always that the top Pro Stock bikes, cars etc. end up running collectors systems? Damn right they work! If you don't think torque between shifts or when you roll the throttle on, then buy those long sewer pipes or some short curly drag pipes you saw on the Discovery Channel.

Emissions Notice California Customers

 Note: We Build to Order

We offer over 700 part numbers in three different finishes including different finishes for the heat shields which are, necessarily, priced separately. In addition, all exhaust systems are available in both  1 3/4" and 2" primary tube diameters and in four different product ranges. We cover everything for Shovelheads to obsolete Clone Bikes and well as odd-ball requests like 145 Inch RSD customs. As for different cylinder heads: OEM, STD, S&S B1, S&S B2, S&S B3 and others are tooled for. It does get complicated. There is no way to pre-configure this which is why we build to order. This is why we cannot offer same day shipping.

All systems save the S&S B1/B2/B3 heads mandatorily require:

00-1000 Billet Gaskets (2) Evo/TC 88 $9.95
00-1001 Exhaust Nuts (4) Evo/TC 88 $3.00
00-1002 Evo/Evo Sportster Billet Steel 2 Bolt Flange and clips (set: 2 flanges, 2 clips); Chrome $29.95

Heat shields are priced separately.

You can order at anytime online 24/7 or call but you only pay when we ship the part. Some people are in a hurry or want us to confrom to their short schedule and get bent out of shape because there is no instant gratification. Everyone gets the same shake. We roll on your say so but on a logical schedule. Plan ahead...Could be 4 weeks could be six weeks or longer. We get lots of calls asking for "Order Status"...This just slows the process down. Everyone here works, no one sits around.

We build four major product ranges listed below. Each of these has a specific purpose.

We offer Five 2-1 Product Ranges

LSR 2-1 Black Hole: Our sound cancelling Black Hole design. For sound issues or if you rack up touring miles.

LSR 2-1 Pro Stock Spyder: Pure merge collector race system with Black Hole sound cancelling technology.

LSR 2-1 Turn Out / Slash Cut: The standard for 2-1 high performance street systems. Baffled.

LSR 2-1 Pro Stock: Merge Collector in Pure Race in Standard and Challenge versions. No Baffle.

LSR 2-1 Pro Stock RaceCat: Pure race system with 450CFM Catalytic Converter and Internal Baffle.

Welded Non Removable Baffles

All LSR 2-1 designs, with the exception of Pro Stock part numbers, have a welded-in, non-removable, baffle.

Our 00-1306R  Pro Stock Resonator designs have a welded-on non-removable Db reducing resonator / baffle.

Slip Joint Designs

All LSR 2-1 designs feature one or two slip joints to insure the pipes will never crack or break. In the case of rubber-mounted engines there are generally two slip joints, B Style being the exception, with one in the rear primary (see above) and one for the front primary into the collector. All rigid mount engines, all the way back through Shovelheads, have the front primary tube slipping into the collector.

We have customers with 20 year old systems with over 100,000 miles with no issues. When you go back over our 40+ year history we have had to deal with different deck heights and all sorts of different motors which meant solid welded exhausts never fit 100% correctly. We also have special fixtures for taller engines like Stroker Sportsters and all the way to 131 and 145" engines. These also feature slip joints.

The slip joints are just that and are not meant to have clamps. We put dab of teflon paste is put into the slip joint for ease of assembly. Some people want to use Permatex Ultra Black...Do not use clamps. They are slip joints.

Real World Tuning Package

When you order a complete LSR 2-1 exhaust with the RSR Air Fuel Ratio Gauge and The TTS MasterTune there is a $75.00 discount on the total price. You can observe while you ride in the real world to evaluate transitionals and wide open throttle . In actual dyno tuning you really have to hold one "site" i.e. the intersect of load and rpm to get an accurate feedback. That's why you see Superflow engine dynos doing step testing.

The problem is things heat up in these air cooled engines and the hidden code in the Delphi ecm starts changing things. You can really only do one wide-open throtte pull and one rpm site before the engine heats up too much. Best do real world data recording with the TTS while you ride and then evauate, in real time, your map with the RSR  mili-second fast RSR Fuel Ratio Gauge. Real time monitoring when you ride is the only way you can evaluate transitionals, acceleration additives, and wide open throttle...all in the real world air and on the road like you do normally.

New Small (12mm) and Older (18mm) O2 Sensors


In 2010 FLT/H series went to the new small heated O2 sensors. The Dynas and Softails went to these in 2012 and the Sportsters in 2014.

We are tooled for these smaller sensors on all the newer models. The small O2 Sensor models have a floating ground voltage offset that has a complex scheme that varies the signal to meet emissions purposes. If you think you are going to trick these you are in for a surprise.

You must specify the year of your motorcycle when ordering the RSR Dual O2 Gauge. Models with the small OEM O2 sensors will require two 18mm O2 ports in addition to the 12mm ones to monitor your bike as you ride. Our RSR Dual Gauges will monitor the 18mm high temperature O2 sensors we supply. It is the only method to monitor both front and rear cylinders of your bike as you ride. Real world observations to perfect your tune. Better than a dyno which tends to overheat your motor quickly skewing your tune.

Dual RSR Air Fuel Ratio Gauge: Late Model (12mm) O2 Sensors (Open Loop Only)


Dual RSR O2 Gauge: 06-1003 Compatible with OEM Delphi 12mm Mini-Switching narrowband sensors if the bike has "O2 Optimizers" eliminating the Closed Loop Function. Real world tuning while you ride...Observe and then make adjustments. Mounted permanently. Waterproof.

RSR O2 Gauge Billet Handlebar Clamp: 06-1025

RSR O2 Gauge Stainless Brackets: 06-1024

12mm Delphi Sensor Wiring Harness and Connectors: 06-1028 Required for either Open Loop Tuning (PCV, Dobek).



We provide the plugs, wiring and hardware to splice the 12mm Delphi Sensors to our RSR Dual Air Fuel Ratio Gauge.  It is the only method to monitor both front and rear cylinders of your bike as you ride. Real world observations to perfect your tune in Open Loop. Better than a dyno which tends to overheat your motor quickly with differing loads in the real world and things like the air cleaner picking up elevated temperatures, and dyno exhaust emissions skewing your tune.

RSR Air Fuel Ratio Gauges...While You Ride


Since we have been doing closed loop fuel injection systems for Harleys for more than 25 years and have been putting O-Sensor Ports in our exhausts for the same amount of time, we have both single and dual O2 ports for our full range of exhausts. Our RSR Air Fuel Ratio Gauge is the best investment you can make for monitoring and optimizing your engine tune.

All LSR 2-1 exhausts come standard with one or two O2 ports (Sequential EFI models)...18mm or 12.5mm. O2 or Lambda sensors are a necessity for either carbureted or non closed loop efi (Weber Marelli and Early Delphi) Harleys. We should know, as we have a lot of experience with them and have been doing Closed Loop EFI systems since 1989.

The Single and Dual gauges ship with six feet of MIL-W-22759/32 wire. The first 24" is Raychem DR-25 sealed on both ends. If you wish to have a connector at the 24" point there is a $50.00 charge to install either six position (single gauge) or eight position male/female Deutsch DTM connectors with Raychem DR-25 sleeving.

The gauge is housed in a hard anodized round enclosure in a standard 2" format with a 2.250" bezel, center back mount, with a 5/16" x 18 stainless socket head cap screw. The gauge will show fuel ratios from 17:1 to 12.0:1 (or richer). The gauge is visible in daylight and automatically dims for nighttime operation. Only a single L.E.D. illuminates.

Very easy to interpret at a glance. Scale is, left to right, lean to rich: three greens, three yellows, two orange and two red l.e.d.s. You simply cannot "read" spooling digital numbers.

The white arrow indicates the maximum power mixture, the second orange light, which is 13.2:1. Transitory enrichments should not, if the engine is warm (>200F Oil temp), go past the first red light. Readings at the far right side of the scale, the second red light, are simply too rich. Proper closed loop operation will cycle back and forth from green to orange around the center of the display.

It is simply the best way to evaluate the tune of your motorcycle and saves valuable dyno time. Mounted permanently. Waterproof.

Mounts....Roll Your Own or Buy One

The gauges have a center back mount 5/16" x 18 x 1/2" Stainless Socket Head Cap Screw and stainless lock washer. You can fab your own bracket for this or use the 06-1025 hard anodized Billet Mount System for either 1.00" or 1.25" handlebars $49.95. Optional is the 06-1024 two piece laser cut 304 Stainless Steel mounting tabs for either near handlebar clamp or up the handlebar mounting: $9.95.

Intsallation Instructions for both gauges can be downloaded in PDF format.

Whether your bike is carb or efi this is the best way to tune...By riding and observing, not on a static dyno. Dynos are not exactly real world in terms of loads, airflow, or transitionals, and even if you had a million dollar AC Transient dyno room, you would still have to do real world testing. The gauges are dead accurate and are millisecond fast responding which makes it very simple to interpret or remember, even at a glace, while you are dodging cars watching for cops.

Anyone who tells you optimizing tuning is easy is full of shit. Engineers at Ford say they spend two years just perfecting tip-in or initial throttle openings. Ride, observe,..then change or edit. Real world.

Pretty soon Harleys will all be watercooled then you really won't be able to tell the difference between Milwaukee and Hammatsu. "The Man" will be sniffing your butt and planting microchips and gps modules up your ass so they can mail you a speeding ticket and keep track of your movements. They already have data recorders on your car so they know what you were doing when the biggie happened. Brave new world. Monitor your engine to get the most out of it before the NSA monitors your tail pipe.

 Follow the light to fulfillment

 The Mother of all gauges! Not a gauge, but a precision tool that will tell you exactly what your engine is doing in real-time. Gives you instantaneous read-outs of air/fuel ratios from 17:1 to 10.5:1 and indicates maximum power ratios. Four color display is easily read in direct sunlight and automatically dims at night. Waterproof, billet aluminum construction. Your significant other will cheat on you but this gauge will never lie! It won't keep you warm at night, but a perfectly running engine will look and sound the same when you wake up next to it the morning after.

Customer writes: "When the gauge arrived I knew it would be of a very high quality, it has far surpassed my expectations. I was very eager to get this installed and take a look at my tune.  Amazing to see how little adjustments on the carb effect the AFR. As a result of this gauge, I have dropped one size on the low speed jet, raised the clip on notch and confirmed the main jet on my Mik48. Thank you, I really like this gauge. Ed"

"Just wanted to follow up with you. This AFR gauge is a game changer. I think the tune on this bike is just about perfect, or as perfect as a one can get with a carb. I have every needle, main and idle jet available for the Mik48 and think I used everyone of them chasing the tune. Now with everything dialed in, warm idle will flicker between the orange and red light, cruise is at the left orange light and hard acceleration toggles between last orange and first red. Plugs look terrific, bike starts first thing in the morning without any choke, while riding around town the lights are relatively stable, some moving around but not much. Again, I couldn’t be happier with how this gauge works.

I am building a 124” TC to put into another FXR that I am building. This gauge is already on the build list, can’t imagine not having this gauge on any of my bikes. Thanks, Ed"

Customer writes: "Sounds like a FAST Harley!  Revs quicker.  Everyone that knows the bike immediately notices how the engine has better throttle response now.  One blip of the throttle is all it takes to spark envy.   It has a noticeable volume and powerful sound on acceleration complimented by a smooth deceleration growl.  Cruising volume is somehow arguably quieter than the V&H slip-ons that were on the bike previously.  The chrome is flawless.  Packaging was excellent.  It’s amazing how spot-on the fitment of the slip joints are.  The mounting bracket is perfect in form, fit and function.  Everything eases into place with a slow methodical hand.  Don’t force or rush the installation and you will complete it without frustration.  I bought the Dual AFR meter at the same time as the pipe.  I cannot imagine an easier way to tune with my TTS MasterTune!  I was able to actually improve the tune and power while maintaining 43 mpg. Thanks! Ryan"

00-1316 LSR 2-1 using RSR Dual Air Fuel Ratio Gauge.

S&S Twin Cam Oil Pump

If you are running one of these and want a "C" Style Exhaust for your Twin Cam engine let us know as we have a different type "C" Style exhaust that fits these pumps. If you are running a normal cone then there are no fitment issues. Our regular "C" pipe goes up close to the original cone. In the case of the S&S pump pictured above we have to route the rear pipe differently due to the "block" shape.

"B" Style pipes are unaffected by the S&S Oil Pump design.

New Exhaust Tech Section

We have given a bit of an overview on the design of Harley Davidson exhaust systems for those who have questions about primary tube length, tube diameters, collector design and the pulsations and wave timing in a V-Twin engine.

LSR 2-1's Down Under

We ship LSR 2-1 exhausts direct to customers in Australia. Middlemen always seem to want to sell things but not actually buy things...and when they do, the price goes sky high and often they order the wrong parts for the customer who has to wait forever... Too many layers.

We "Build to Order" all systems no matter who you are or where you are and do not try to fill distribution channels full of parts. Offering 700+ parts numbers in four different finishes and in four major product ranges from Full Race to Quiet gives our customers the exhaust system best suited for their intended purpose. We ship FedEx Economy on Mondays and Thursdays.

S&S T143 with B3 Heads

143 Cubic Inches for your Dresser. Another way to spend $10,000.00 to $15,000.00 to climb the Horsepower mountain. We are making exhausts for these with out integral two bolt B3 flanges. The exhaust port dimensions are not OEM Harley. There are slight variations between the B1/B2 and B3 S&S heads.

We have made custom parts for these two bolt T143 B3 cylinder heads. Available for the four product ranges we manufacture...Quiet (LSR 2-1 Black Hole) to Full Race (LSR 2-1 Pro Stock). All use 2" primary tubes.

The new two bolt LSR 2-1 B3 Flange is integral, free rotating, to the exhaust port. Full tapered cnc machined venturi for 2" primary tubes.

Uses a machined1.875" I.D. Billet Alumiunm Gasket.

Belts won't last on these 143T motors so we offer chain drive/swingarm conversions for 09 and later Baggers. Used by S&S on their T143 test bike.

S&S SA B1/2/3 Heads

We have been asked by customers to provide LSR 2-1 exhaust systems for B1 / B2 / B3 heads originally found on EVO and 145" S&S Tribute engines and later T143 engines. Early B1/B2 four bolt flanges. Later B3 use two bolt flanges.We make both. The diagonal dimensions are the same two to four bolt patterns.

We have LSR 2-1, LSR 2-1 Pro Stock, LSR 2-1Pro Stock Spyder and LSR 2-1 Black Hole designs for these three S&S cylinder head variations.. Pictured above are our laser cut flanges and cnc machined hour glass shaped venturis that we heliarc to the B1 / B2 / B3 LSR 2-1 exhaust systems.

We have a specific fixture for the 126 S&S and T143 SAB2 / SAb3 Twin Cam Dresser systems as the billet cam cover is not OEM.

Baffling Alien Discs and Aluminum Butt Plugs

Our testing has shown that the Harley V-Twin is extremely sensitive to back pressure which is why 2-1's that use small or restrictive collectors don't breathe well, and why restrictive baffles shut the motor down. Disc type baffles are good for spark arrestors on dirt bikes but they have no place on a big inch V-Twin. You don't make power by adding restrictions to your exhaust system whether it's a bunch of stainless discs or some damn piece of aluminum billet machined into a Harley butt plug! Ever wonder why they had to put a hole up the center of the discs? Well, one reason was the discs are so damn restrictive you have to have several pounds of them to get enough flow through their waffle shaped passages. Good mufflers, but they have nothing to do with performance and they sure as hell do not create vacuum as has been claimed. When you get confused by all the bullshit simply ask the following question.." Do they run them in NASCAR or in Formula One?". Nope, they run straight pipe collector systems without any stupid discs or aluminum butt plugs.It's always funny how when the money is on the line, all the little things like discs, billet caps, anti-reversion flaps, reverse megaphones and other such nonsense somehow don't make the field.

One Size Does Not Fit All

Oh, the joys of mass production. It is so easy when you are pumping out tubes with low priced help to compromise and make all your primary tubes one size. Split the difference, cover your ass, ride right up the middle and fill the distribution channels with "one size fits all". Turn up the promotion, andodize some butt plugs, come up with a tricky name that sounds like something from NASCAR or a Godzilla Movie, declare your superiority, get your product in the press, publish some dyno charts and head for the bank. Hey! It's just numbers on a sheet of paper and the one with the biggest numbers wins.

This is the strategy used by manufacturers who use 1 7/8" primary tubes instead of building both 1 3/4" and 2" primary designs as does RB Racing.

Evo and TC88 cylinder head castings both have exhaust pockets that are about 1.920" in diameter. The exhaust port is much smaller than this with a large cross-section diameter of 1.600", but an actual area closer to a 1.500 circle. These are high velocity ports. The quickest way to kill power is to put in bigger exhaust ports or too large a primary tube as the gas speeds drop and, as speeds drop, the pressure rises which results in less scavenging.

This is why Harley uses 1.750" primary tubes with and I.D. of around 1.625".

Once the motors get bumped up in displacement and cnc ported cylinder heads are installed then the picture changes. Going from 80 or 88 cubic inches to 117/124/126/135 cubic inches represents more than a 50% increase in air being pumped out the exhaust port. A 1 3/4" or 1 7/8" design is just to small. Bigger motors require 2" primary tubes.

"One size fits all" may make economic sense in terms of production efficiencies, but it doesn't make sense for your engine.


Customer writes: "First, I have had your LSR 2-1 C w/Turnout on my 98 FLSTS for about 4 years and 32,000 miles. It looks great, sounds great, and of course, performs great.

Second, the mechanic that works on my bike also drag races a Shovelhead powered FL. He only ran Thunderheader until he rode my bike and did some research. Steve had you guys make him a 2-1 and set new records in his class.

Third, my brother-n-law has a '05 EFI Road King. He was just dying to put some Rinehart true duals on it. I talked him into waiting until he looked at and listened to a lot of RKs before buying. During the year he did this I kept asking what he wanted out of the new exhaust. Finally, he admitted sound and performance. He kept saying I love the sound of your bike and it is fast as hell. So, I suggested the LSR 2-1 C Slash Cut longer pipe. We installed your exhaust, a PCIII usb, and a K&N filter with stock a/c cover and changed the backing plate. His road king has torque and runs like a scalded dog. We both can out run 95" kits installed at the HD dealers.

I provided the background to say this. My B'law took his RK to the HD dealer for the 15k maintenance service. The mechanics went nuts over the exhaust and what it does for the performance. They asked all kinds of questions. They had never heard of your firm or the exhausts. Now comes the kicker and it makes me a little sad (because I have enjoyed having an exhaust that out performs the crap the HD dealers sell). The mechanics conclusion. They are going to take off that HD exhaust crap (their words) and get RB Racing exhausts. Now the word will spread around Memphis and RB Racing exhausts will be everywhere.

It was good while it lasted - having the performance edge over others.

Your exhaust system has been great on my bike for 4 years and 32k miles. Thanks for a great product. I can't imagine having any other brand of exhaust!

PS. Sure wish you would make a LSR 2-1 for Victory Jackpot or 8 ball. The only reason I haven't purchased one in the last two years is because you said you would NOT make a Victory exhaust.


Self-Tuning Myth

People have the idea that closed-loop systems are completely self-tuning and that they are going to sell you some add-on gizmo that will automatically tune your efi bike. This is a crock of shit. The truth is that every engine is different and, in the Harley world, difference is the norm as there are limitless engine build combinations.

In Detroit, Japan, or Germany, they spend thousands of man-hours developing base maps for their automotive applications. On top of these base maps goes the closed-loop feedback mechanism controlled by mathematical equations or algorithms that govern exactly how the closed loop operation will function. These base maps are not written so the vehicle will run perfectly without feedback i.e. maps are not designed for open-loop operation. The strategy for closed-loop operation is different as fuel requirements under different climatic and altitude differences can be as much as 30%. Unless the base map is constructed for the particular application, the O2 feedback mechanism will not work properly.

OEM correction schemes allow only very slight learning corrections or they will "throw" an error code. They do this for a very specific reason i.e. if things are going wrong, which is indicated by the system trying to correct out of bounds problems, then a sensor or something else is wrong. They are not designed to make large swings to correct calibrations that are way out of bounds.

14.7 / 13.2 = 1.11

People take their perfectly good Delphi electronics and swap them for a self-tuning "Wide-Band" system. The "Wide Band" manufacturers tell you to run their systems at an air/fuel target of 13.2:1. This simply puts 11% more fuel through the engine, i.e. if you were getting 40 mpg @ 14.7:1, you are now going to get 35.6 mpg. You might as well go get a carburetor.

The objective of closed loop and narrow band sensors is to get the most efficiency out of your engine by targeting 14.7:1 except in warm-up, sudden transitions, and wide open throttle, as well as hard decelleration and or fuel cut-off. Ratios as lean as 17.0:1 can be run under decelleration and certain no load situations.

FYI maximum constant torque occurs around 13.2:1, whereas sudden transitions can be anywhere from 12.5:1 to 10.0:1 depending on temperature conditions. It isn't simple. EFI isn't Linkerts, Bendix or S&S simplicity. The closest carb you can get to efi fuel control is a CV Carburetor.

Beyond Stupid

Some add-on boxes for late model O2 sensor equipped oem Harleys eliminate the O2 sensors altogether. Why in the hell would you want to take a self-adjusting, sophisticated system and turn it into a gas guzzling low mileage dumb efi system? Beats the hell out of us and, since we make closed loop efi systems, we do have some experience in this area.

Your bike should be left in closed loop, tuned in closed loop and monitored with O2 displays in closed loop. Correction factors defined in the oem code cannot be exceeded. Maps have to be rewritten for the changes to the bike so the base map is in agreement with the oem algorithms.

Phone Sex and Remote Tuning

In some sort of logical disconnect a few customers call us up wanting us to tune their bike over the phone and then become increasingly indignant when we tell them it just doesn't work that way. Now, we spent the better part of 14 years, starting in 1976 working on carburetors, jetting, needle design, and even designed and marketed a flat slide carb for the Harley market. Thousands of man hours representing about 5 months out of every year were devoted to jetting issues. It got to be a real issue i.e. it was an interesting experience to define what the correct air fuel ratios should be, experimentally figure out how to measure them, and then deal with tuning die cast critters, often modifying them with extra circuits etc. but, in the end, it was temporal and an endless loop that did not exactly pay the bills.

We did learn how to make things run well, not that anyone appreciated it. It was fun to watch people try to beat you when they couldn't. Knowledge. Hard work.

Since 1989 we've been working on and manufacturing closed loop fuel injections systems for Harley Davidsons and have set numerous Bonneville, El Mirage and Maxton speed records and won drag racing championships with them. We spent over 3000 man hours writing and perfecting Autocal.V6 prediction and analysis software for our RSR Fuel Injection systems. Why did we spend 3000 man hours? Well, we didn't plan on it, and it's a good way to flirt with insanity, but we saw no other option as digital efi requires hundreds of decisions, all of which are intertwined. No more brass jets. Exponential combinations. Changing points, one at a time is sheer insanity. Progress comes with increased complexity.

These days all Harleys are closed loop fuel injected with a single throat throtttle body and are speed density Delphi systems, all very complex. It's the same formula we decided on 18 years ago. The only thing we suggest is that you use O2 signals to monitor and tune the system as the sensors are millisecond accurate and must be monitored at the exhaust port where temperatures are high and as far away from the outside oxygen rich air as possible. We suggest you use software, not hardware, to adjust your system using our RSR Air Fuel Ratio Gauges and keep your bike off of the dyno until the lights in these displays tell you your mixture is correct. Engines operate in a very narrow realm of air fuel ratios. If you want to go to the dyno after this...fine.

Just don't call us breathlessly demanding we tune your bike over the phone.

 Superflow CycleDyn...Testing a Running Motorcycle

If you are going to use a chassis dyno it has to be a tool and not a toy. At RB Racing we use the Superflow CycleDyn as it best emulates the real world. We use it for development and not for publishing "dyno charts". Most of our work is with Pectel SQ6M controllers which have extensive internal datalogging and playback capabilities up to 2000Hz sampling rates. With the Superflow we can program specific tests and transient sweeps with our turbocharger systems up 750 hp in inertial mode or 500 hp in Eddy Current controlled accelerations.

For those of you who like Dynojet "Dyno Graphs" this article.

Steve Cole (TTS MasterTune) who has spent untold thousands of hours on every dyno imagineable has this to say about CycleDyns:

Steve Cole: "In the development side what I can say is the SuperFlow when setup properly emulates the real world much better. As an example the only way to get a DynoJet to give you HP and TQ is a WOT unloaded run. The SuperFlow allows that plus just about any other combination you like with real torque output. So what does any of it buy you becomes the question. I can tell you that if we tune to a DJ and get the best we can, then repeat on the SuperFlow using real world acceleration rates for the engine being tested the results are very different. Take the final calibrations and run them in both dyno's unloaded and the DJ developed type calibration will show the most HP and TQ in those conditions, on both the SuperFlow in DJ mode and the DJ. Then take the SuperFlow controlled condition calibration and load it in the bike the power will go up when tested in the SuperFlow mode again which can only be done on the SuperFlow.

Now the hooker, take the bike and put one of the finished calibrations in it and give it to the customer and say go ride it and come back after you've ridden it well, to know how it feels/runs. They come back after an hour or so then load the other calibration and ask them to do the same riding over and come back again. Each and everytime we have done this every customer has picked the calibration that was done on the SuperFlow under the controlled acceleration modes! So pick what works for you but there is a difference. Does it take longer, does it end with a measurable difference............. YEP!"

When we have turbo bikes like our Road Glide Turbo it gets a bit interesting to go testing in LA traffic with police, cell phone cameras, and freeway cameras. We still do real world riding with data acquisition as the real world is where you ride.

People want "Dyno Sheets"...see below. We aren't going to test every damn camshaft, compression ratio, piston confguration, cylinder head etc as there is not enough money nor time to do so. However, we do testing for our own race development, R&D, and our personal development platforms. These optional $5,900.00 internal "High Pressure Blowers" provide cool airflow to match road speed 1:1 up to 180 mph. Air is also directed to the rear tire. The CycleDyn is calibrated at Superflow at the time of manufacture to measure and account for this additional drag.

Aerodynamic drag in terms of frontal area can be part of the dynamometer programming...useful for Bonneville simulation.

When we have turbo bikes like our Road Glide Turbo it gets a bit interesting to go testing in LA traffic with police, cell phone cameras, and freeway cameras. We still do real world riding with data acquisition as the real world is where you ride. We used to go to the drag strips...then they closed all of them. Then we used to ride way out to Avenue "A" in Palmdale for 200mph testing on a two lane road with low flying pheasants and farmers with tractors crossing the roads. Society does close in you you.

Dyno Sheets

People call us all the time asking for "Dyno Sheets" and we patiently tell them we do not provide self-serving graphs predicting fantastic horsepower and torque gains. Plenty of customers send us dyno sheets but, as we've been at this a long time, we know the tuning game is too complicated to provide numbers just to sell an exhaust. Tuning is a multi-variable process.

When the EVO motors came out Jerry Branch published his famous manifesto on tuning 80" EVO motors...In short, unless you bumped the compression the horsepower was not forthcoming. Same these days. In 2014 John O'Keefe of Branch O'Keefe ran an extensive series of tests on OEM Twin Cam cylinder heads to see if he could offer a "less expensive" ported head as everyone with a grinder in his garage was suddenly an expert at cylinder head porting. John found out that any attempt to clean up the ports killed the flow and port velocities dropped. He scrapped that idea and kept his well-proven chamber modification, porting and valve replacement system.

Logic seems to be in short supply when it comes to tuning. Tuning is not a pipe changing exercise. The world these days is full of customers who agonize endlessly over what to buy and then dump these parts on some unsuspecting "shop-tuner" expecting miracles. It just isn't going to happen. Coordinated development is expensive and time consuming. If it was NASCAR developer they might spend days searching for a few hp or a different curve for a specific track.

If you are looking for warm cuddily sheets we are clean out of them. We are tuners and you can buy all the trick parts in the world and a guy with a well tuned mild bike with a good power to weight ratio will kick your ass. Real world. Find a good tuner or become one. Look in the mirror.

Screaming Eagle Super Tuner...SEST (discontinued)

"SEST" or Greek for the worst written instruction manual we've ever seen. We defy you to figure out how to get various charts and graphs to open and how to get to the advanced versus basic tuning options. We suggest you look around the internet as the manual is of little help.

We bought one of these to see what was involved. If you can figure out the software navigation issues and install a map that somewhat matches your bike, you simply ride around, observe the RSR Air Fuel Ratio Meter display and make edits. The tuning is fairly straight forward. Without the Dual Gauge we don't know how you would do it. We just ride.

These days Harley only offers their "Street Tuners".

Steve Cole's TTS MasterTune


Before the Screaming Eagle Super Tuner (SEST) there was the SERT or Screaming Eagle Race Tuner. Acronyms, what would we do without them? Steve Cole was the guy behind the SERT until Harley decided to go with another contractor. Money. It's always about the money. Since Steve designed the original stuff, this new stuff i.e. TTS MasterTune is easier to use and has one benefit that the "SEST" does not have...You have the ability to save and restore your original calibration. In addition with the Green Analog Interface Model you can log up to four analog channels like Wideband Sensors.

We prefer software solutions to tuning late model efi Harleys and not use any add-on boxes or to replace the entire system with some "self-tuning", throttle-angle based, wide band controller. There are simply too many problems technical-wise with wide band sensors...Stuff they do not tell you about like pressure and temperature compensation issues and sensor latency. You are better off with the OEM O2 sensors. You won't believe this but that's your problem.

One point no one is going to tell you is that Harley has hidden tables that will richen up your injectors if you hold the bike under load, like on a dyno or wide open throttle for any amount of time beyond "x". They don't want you to fool with this. Guess what happens to those people who tune under full load.

MasterTune BT Diagnostic and Development Tools
Communication Interfaces

The MasterTune BT Communications Interface is the tool that provides 2-way communication between the bike's ECM and a Windows-based laptop/PC utilizing the MasterTune BT software. The interface also provides stand-alone data logging for diagnostic and calibration support. The MasterTune BT software package can be downloaded for free at

Part Number 

MasterTune BT Communications Interface - CAN 6 Pin (2012-2020) (Gray) 

When used for calibration development, this interface marries to the ECM during the first ECM flash and further calibration development can only be performed on that ECM.
When used for vehicle diagnostics and data logging, this interface can be used on any compatible vehicle, even if already married to an ECM.

Mastertune BT Interface communicates to the PC via a wireless Bluetooth connection. Also includes a support loop to attach the interface to the bike via a wire tie.

Compatible with the following Delphi equipped Harley-Davidson Motorcycles:
    •    Touring models 2014-2020
    •    Softail models 2011-2020
    •    XL Sportster models 2014-2020
    •    Street models 2015-2020
    •    Dyna models 2012-2017
Works with the following MasterTune software products:
    •    MasterTune BT
    •    DataMaster BT
    •    VTune BT
    •    Flight Recorder


Part Number  2000021


MasterTune BT Communications Interface - CAN 6 Pin (2021+) (Red)
When used for calibration development, this interface marries to the ECM during the first ECM flash and further calibration development can only be performed on that ECM.
When used for vehicle diagnostics and data logging, this interface can be used on any compatible vehicle, even if already married to an ECM.
Mastertune BT Interface communicates to the PC via a wireless Bluetooth connection. Also includes a support loop to attach the interface to the bike via a wire tie.
Compatible with the following Harley-Davidson Motorcycles:
    •    Touring models 2021-present
    •    Softail models 2021-present
    •    RevMax models 2021-present
    •    (Sportster & PanAm)
Works with the following MasterTune software products:
    •    MasterTune BT
    •    DataMaster BT
    •    VTune BT
    •    Flight Recorder

In the late 70's, all through the 1980's and into the mid 1990's we used to spend about 5 months out of every year tuning things. No time for that anymore. It's best that you tune your own bike...add up the hours and write yourself a hot check. Or just pay somebody. We use a Supeflow CycleDyn Dyno and we ride in the real world using our RSR Air Fuel Ratio Gauges.

TTS & Exhaust Combo Military Discount


We offer a combined 10% discount to active or prior service both US Militaty and the Coast Guard on LSR 2-1 exhaust purchases with TTS Tuners and Cable Kits,


Whenever you look at an exhaust and see it caked in black soot you know the bike is not running or tuned correctly. Back in the mid 1980's we did a carburetor development program for Keihin Corporation for their 41mm CR Race carbs on both Shovelheads and the new Evolution motors. When we were finished the bikes got 56 mpg cruising and 46 mpg if you ran them harder...and after 500 mile tests the pipes were perfectly clean inside and the exhaust ports were dead clean.

If you take the exhaust system off a modern Closed Loop BMW, as we have, you will find them dead clean or whitish inside. Harleys should be the same.

We always ask what mileage people get from their "tuned" or modified Harleys after "Dyno tuning"....The universal answer is 37 mpg or less. If they don't know, we ask them if they have to gas at 100 miles. Most do.

Once a customer bought an exhaust from us and took his bike to two different dynos in search of the "117 Hp" he was looking for for his 103...He got 110Hp. After pissing and moaning we told the guy to give us our exhaust back and we found it caked in soot. So much for tuners and their tail pipe sniffers that see lean reversions...They just kept adding fuel. You tell the customer to put on our RSR Air Fuel Gauge to monitor the mixtures F/R in the real world...No, they want a "Dyno Tune". We have dynos...we know what they do and can't do.

Logic plays no part in people and their toys. EFI is complex...put in larger injectors and all of your warm up, synchronous and asynchronous fueling is out the window, Brave new world.

No soot.


Pictured above is the exhaust port from a 2017 Dyna Low Rider S with about 100 miles on it. No soot. Delphi engineers seem to have done a very good job. Looks like the port you would see on a BMW. Now, when your "Tuner" gets finished with it, it will most likely be full of soot. Logic plays no part in people and their toys. EFI is complex...put in different cams, change air cleaners, port the heads and all this goes out the window. Brave new world.

No soot.

Tuning and Development  Stories

Back in the 1980's we developed a 38mm Flat Slide Carburetor off a Mikuni casting that was only used in Japan. We called it the "PowerMaster". Mikuni American Coropration was sort of upset about this and wanted to take over the project, but Mikuni Japan told them to let us do it. We added an accelerator pump that we manufactured and got the Shoveleads and EVO's working well and, at one point, even developed an electric automatic choke mechanism as people were too lazy to pull an enrichening knob. Mikuni American Corporation simply doubled our prices for the castings from $70.00 to $140.00 each after we sold several hundred carbs, so we dropped the project. Since we had all the data, Mikuni USA asked us to develop a 42 mm Flat Slide for the Harley Market that was originally made for Vance and Hines inline-4 Jap market. We declined.

Keihin Corporation then asked us to develop the 41mm CR Carb for the Harley Market. We tested the carb on Shovelheads and EVOs getting 54-56 MPG and turned the data over to Sudco Corporation after doing altitude tests to 8000 feet as well as hot soak testing.  Kehin actually asked us to do long idle tests with the bikes leaning to the right even though we told them all the sidestands were on the left.

Sometime later we ordered a 41mm CR Carb from Sudco and took it apart. We called them up and asked if they had done further testing and , if they had, what mileage did they get. The answer was yes and they were getting 37 MPG...We responded "That was what we thought".

We installed the Keihin 41mm CR on new 1995 Dyna with our original needle and jetting and the customer ran the bike on a 500 mile run. We pulled the exhaust off after the run and it was perfectly clean inside. He marveled at the mileage as his friends had to fill up and he just topped his gas tank off. The bike would pop wheelies easily with a dead stock engine and could do no wrong. The customer then took the Dyna to another shop and had some work done and a cam installed. He brought the bike back to us to look at. We looked at the exhaust and it was full of soot. One ride around the block proved the bike was gutless and way out of tune. We told the guy it ran great as we did not want to get involved.

Usually it's people's inability to tune. 99% are just parts changers. There is no science in part changing. Guess who gets blamed...The exhaust manufacturer.

Backpressure Physics

We are going to state this very clearly...Backpressure does not increase horsepower. Period.

An often heard statement from the well-informed is "You need a bit of backpressure for an exhaust to work". Usually this comes from someone who is not a tuner or someone who is faced with a situation where he does not have the tools or means to adjust things. Anything you do in the exhaust will change the flows, the pressures, or velocities somewhat. The correct scenario is that the exhaust has to be properly designed and then you optimize the jetting, ecu data inputs, camshafts, port dimensions, valve sizes and the like. The exhaust has to be designed for the intended use.

This all dates from the early 1980's when Supertrapp invented a muffler designed for dirtbikes to trap potential sparks, or burning, carbonized, bits, so it could have US Forrestry Approval for off-road use. The "trapp" tells what the intended purpose was. If you wanted a Harley to barely work you had to stick a couple of pounds, or about 23-25 of these discs in the end of your exhaust. Of course this didn't really work, which is why they ended up putting a hole up the middle anyway. You don't tune an exhaust.

Your engine has 15 psi (1 Bar) of atmospheric pressure sitting at the inlet and another 15 psi lurking at the end of the tailpipe. The inlet stroke creates a pressure differential and the atmosphere goes rushing inward. The exhaust valve opens and there is a pressure rise in the tube followed by a strong vacuum signal as the gases head down the pipe. Note that we said "vacuum signal."

Pressure differentials can be seen in the exhaust of a jet engine. We have a high pressure pulse coming out our exhaust system but it's just not visible as in the photo above.

The pattern of evenly spaced rings sometimes visible in the exhaust of jet engine is typically referred to as shock diamonds or Mach disks. The phenomenon occurs anytime a flow exits a nozzle at supersonic speeds and at a pressure that is different than that of the external atmosphere. Most of us are probably used to seeing shock diamonds occur near sea level during the takeoff of an aircraft, like in the above photo of the SR-71 Blackbird.

Logical extremes are often used to illustrate a point. For those who argue that backpressure can be a help they might say, from an extreme position, "Let's throw away the exhaust system so we have no backpressure at all". They would then conclude that the motor would run like crap and we would agree completely. The only problem is that they haven't gotten rid of backpressure, they simply have introduced 15 psi at the exhaust port and have given up any inertia, gas speeds or vacuum signals that exist in a primary tube.

The vacuum signal or low pressure that follows an exhaust event can be used to help scavenge the cylinder during overlap when both exhaust and inlet valves are open. Conversely, during this overlap period, the increase in backpressure can cause these burnt gases to re-enter the combustion chamber and contaminate the inlet charge. Result...loss of power.

The proper way to look at exhausts is to view them as a way to maintain the highest velocity that will not impede flow. As velocity increases the pressure drops and the engine can become more efficient. We have all the variables of length, diameter, rpm, collector size, internal shapes and the reflective waves that all this causes. There is no "one answer".

For those of you who disagree because of anecdotal evidence we would agree with you also. Stick your finger, washers, or whatever up an exhaust and it will change things. Altering an exhaust's flow can correct someting else like mixure or spark timing. In the end, if you have to throw it off a cliff to win, do it. Only results count and if increasing backpressure helps your situation then do it. We use baffles that do not impede flow (power) but maintain high exhaust speeds (lower pressure). People are, by in large, not tuners just part changers...We spent years doing drag strip testing before the land got too expensive to determine the internal shapes of the exhausts.

People who take our advice and use our RSR Air Fuel Ratio Gauges to tune and monitor in the real world get the best results.

As a final thought...Gale Banks doesn't make money selling increased backpressure exhaust systems. Think about it. That picture above is a dedicated exhaust backpressure gauge. We use them and we design our systems for minimal backpressure.

Broomstick Myth

There seems to be a myth about broomsticks and tuning which goes like this "If you can stick a broomstick up your exhaust you won't be able to tune your bike". Well bippies, we went through that more than 35 years ago when the EVOs came out....and well though the development of our own fuel RSR injection up through the high end Cosworth ECUs we use these days...not to mention OEM Delphi systems. Forget the useless Weber Marelli.

Go to the dragstrip with an exhaust that only bypasses enough air for a 1.0" diameter broomstick and you'll be on the trailer when the engine signs off on the big end (power). This myth continues because of slow reacting Lambda Sensors placed incorrectly in the exhaust system and or control systems using Alpha-N (Throttle angle/rpm) which try to control in real time all the shit thats going on, having too much authority to correct things instead of incrementally learning. Some exhaust system manufacturers place the O2 sensors where they simply are going to read incorrectly. Steve Cole of TTS MasterTune can tell you horror stories about this. Then the "Tuner" then wants to choke up the pipe to stagnate things to get a reading.

We run our Pro Stock systems with no baffles under our RSR closed loop efi systems. No broomsticks and O2 sensors very close to the exhaust valves and get over 50 MPG. At W.O.T. you don't look at Lambda and you don't want a restrictive exhaust.

Internal system shapes will determine when reflections occur. Sticking a slow reacting Lambda probe up the rear of the pipe only half way to the exhaust ports is patently stupid. People keep doing in anyway. Best use our RSR Air Fuel Ratio Gauges with Lambda sensors at the exhaust ports.

Fuel Injection..A Reality Check

OEM HarleyDelphi Injectors come in various ratings: 3.91 grams/second; 4.35 grams/second; 4.89 grams per second (CVO); and 6.00 grams per second. These ratings are static i.e. shorted open. Pulsed static is about 90% of this i.e. what you could expect if you maxed them out in your ecu calibration software. If you hold them to an 85% duty cycle they, respectively, offer the following horsepower potentials: 105 hp; 117 hp; 131 hp and 161 hp. Now, you can squeeze more out of them by going past 85%, but this is the point where they are still controllable.

We get calls from people building wazoo big engines and they are still running the stock injectors. We suggest you get the right injectors for your engine building projects. We offer a several calculators for those messing with efi systems. Fuel Injector Calculator   Professional Injector Pulsewidth Calculator.

To see what lengths we go to to cotrol 360 hp on turbos take a look at our Road Glide Fuel System.

Band-Aid...Not Needed

If you have a late model Harley with a Fly-By-Wire throttle you do not need an add-on gizmo. We suggest you get Steve Cole's TTS Master Tune software described above. When purchased with RB Racing exhausts and turbocharger systems we offer a $50.00 discount i.e. $375.00 v $425.00 list. TTS MasterTune allows you to adjust your electronic throttle without the expense of additional add-on devices as well as your fueling and everything else in the Delphi ECU.

O-Sensor Ports Standard....New Dual O2 Meters

For fuel injected models our Dual Gauge monitors front and rear cylinders in real time in the real world. Invaluable for tuning. Depending on the year and model these tie into high temperature Bosch 18mm O-Sensors. Permanently mounted, waterproof and has an optional 1.0" or 1.250" billet handlebar mount.

For LSR 2-1 Exhausts late model bikes with 12mm O2 ports have these ports in the standard oem location and secondary 18mm ports are installed (if ordered) for the RSR Dual O2 Meter Bosch O-Sensors. 2009 to 2016 Dressers have the 12mm O2 ports near the transmission and we place the RSR 18mm Bosch O-Sensor ports near the exhaust ports where they should be.

Wideband O2  Adaptations

Systems that typically use Bosch LSU 4.2/4.9 wideband sensors for self-tuning have a built-in problem. First, the "map" has to be correct before any of this self-tuning takes place. Secondly, the real issue is the sensor response time, i.e. the time it takes the sensor to stabilize, and for the ecu to make a corrected output. No matter what they tell your there is a significant delay between the reading and the correction, during which time the engine will be at another rpm/load site . This can be on the order of 980 Ms for the Bosch Wideband sensors which is why, in dyno testing, they use step tests for a number of seconds, letting the engine stabilize at specific load/rpm points, before any measurements or changes can be done. Constantly rewriting RAM locations with "corrections" on the fly is never going to be correct.

Think about it...A high revving sportbike can gain rpm at 40,000 rpm per second per second...Where in the hell was the O-sensor reading on the fuel map? O-Sensors are a "Trim-Function" device not an absolute control strategy. The base mapping must be correct and you do not accomplish this by any form of auto-tuning. Not even in Formula1. Typically a new Harley can deliver 50 mpg...When these auto-tuners, ecm rplacements or ecu intercept boxes finish their never-ending editing you are suddenly in the 30 mpg range. This is not a good strategy.

The OEM narrowband Delphi system actually works twice as fast  500 Ms and the map, as delivered by Harley, is correct. The Delphi ecm has the ability to adjust about 20% in small increments (block learn multipliers) to factor for air cleaners slowly getting dirty etc. It already is self-tuning in a trim function capacity.

In short, taking off your fast acting, self-calibrating, Delphi system is just plain stupid. Use TTS MasterTune and adjust your font and rear Volumetric Efficiency Tables by observing our RSR Gauge in actual riding. Don't screw around with ignition timing...about 32 degree full advance at W.O.T. is damn close.

Mounts....Roll Your Own or Buy One

Dual RSR O2 Monitor (06-1003) to the right and ORCA Gear Position Indicator to the left. Dual O2 monitor displays real time readout of front and rear cylinders. Ride the bike, observe and then adjust. Correlate rpm and load and change what you need to change i.e. richen or lean these areas. Cheaper than a dyno, and easier than trying to datalog things. The real world is where you ride...monitor it there. 1" or 1.25" cnc machined handlebar clamps. Part # 06-1025

Road Toad...The Movie

Harleys vibrate. Next time we'll make a better camera mount. Video shows the gear indicator in action on a 5 speed 2004 Road Toad as well as our RSR Dual Air Fuel Ratio Gauge. We made a few edits to the TC88 ECM for our LSR 2-1 Pro Stock Spyder exhaust. Gives you an idea of how we tune things by actually riding them and how useful the Bonneville Gear Indicator is.

Get a tub of popcorn and a six pack and watch a 2004 FLTRI find happiness going through the gears. Make your own movie and get some more popcorn and beer and show your friends how you hit redline in sixth gear. At Bonneville we run five gears but we have a 425 hp Harley...and a lot of beer.

Handlebar Billet Mounted Bracket: Three degrees of freedom. Stainless hardware. Part Number 06-1025. For single or dual O2 meters. Meter has a 5/16" x 18 center back mount should youy decide to make your own mount system. 1.25" bars pictures left above. 1.0" bars to the right above.

We have been making single RSR Air Fuel Ratio Meters (pictured to the right above) for over 30 years. All LSR 2-1 exhausts for the last 30 years have come with an 18mm front O2 port standard. Perfect for monitoring and tuning carbureted applications. All LSR 2-1 exhausts can be ordered with two O2 ports regardless of year at no extra charge. The gauge tells you the truth whether you want to know it or not. Knowledge is never easy and since "tuning" is a knowledge-based exercise there is no microwaveable, instant mashed potato solution to the truth.

Get the gauge, single or dual display, and become your own master chef. Single gauges are for carbureted applications where you only monitor the front cylinder. The rear cylinder is shrouded and runs hotter and requires less fuel. Targeting the front cylinder biases the rear richer that the front. Trust us, we have lots of experience in this.

Of course it's always easier to yell into a telephone or berate your tuner. Grow up. You bought the bike. Learn to adjust it.

LSR 2-1 Sizing For Your Motor - Click on photo to enlarge

RB Racing LSR 2-1's use large 3" diameter collectors which are perfectly mated to our 1 3/4" or 2" primary tube diameters. Both our 1 3/4" and 2" designs feature our CNC machined Turbo Venturis for maximum flow. We often are asked which is better, the 2" or 1 3/4" design...The answer is how big or how modified is your motor. If you are planning to go over 100 cubic inches then go to a 2"primary tube design. We have customers with high output 96" S&S motors that routinely pump out 112hp with 2" Style "B" 2-1 LSR systems. Normally we say a 96" S&S motor is better off with one of our 1 3/4" designs as there is generaly more torque available at lower engine speeds in the 2000 to 4000 rpm range. If your motor is a 113 c.i. or 124 c.i. S&S motor or a 113/126/132/139" ORCA engine then you should go directly to a 2" design.

800 Horsepower LSR 2-1 Slash Cut

We're not really sure what a 2-1 has to do with Top Fuel Nitro motors but when Carl Pelletier asked us to make a collector for his top fuel 175c.i. PRP motor we whipped up a 4" diameter collector and sent him the tooling. Take a Tour of what it takes to run a top fuel bike. Doug Vancil's hard running Top Fuel Harley sponsored by Vance and Hines has a 2-1 that looks like one of their Pro Pipes so when Carl asked us to build one we made sure the collector area wouldn't restrict each of the 400hp explosions that were coming from each cylinder. Carl qualified 8th out of 32 bikes at the final Las Vegas meet and ran in the sixes at over 200 mph so the 2-1 probably didn't hurt anything. His best speed is 214mph with the 2-1 so it didn't seen to hurt anything. Top Fuel is pure insanity and is addictive as Heroin for those involved. Like they say " Gasoline is for washing parts...Nitro is for Racing!".

Potato, Potato, Potato

The sound our 2-1's make is so "right" that customers want them for their sound alone. They have a much more powerful sound because the engine is working easier and the power is much smoother. LSR 2-1s wound out to the max get everyone's attention because they sing the song that only a power junkie would love. Everyday we talk to customers who have tried every pipe on the market and can't believe how much faster the LSR 2-1 is throughout the RPM range. You can expect horsepower gains from 6 to 18 hp over any other design.

On the sound issue, we keep getting asked what a particular pipe sounds like, to which our answer is "It still sounds like a Harley." For those of you who can't remember what your bike sounds like we suggest you buy a small tape recorder ... record your bike and listen to will hear the siren call of the open road and a faint "Potato, Potato, Potato". If this sound doesn't please you or tickle your fancy record a Honda, a Ferrari or your old lady snoring and hook it up to your headphones while you're riding...that is what your RB Racing LSR 2-1 will sound like. One final time, LSR pipes sound like a Harley!...We will tell you they aren't as noisy as a tinny, cheap-ass megaphone! Harley tried to patent the sound "Potato, Potato, Potato" but finally gave up after 5 years of legal hassle.

LSR Baffles are welded into the tail section, have tapered entries and exits to smooth the flow, and never require any maintenance! We aren't stupid enough to weld in some flat plates that belong in sardine cans not on a high performance big twin! LSR 2-1 baffles are designed to achieve the same performance as would an "open" pipe, but provide a small amount of back-pressure to to increase low speed torque by preventing cylinder "blow-down" on camshaft overlap. Actual drag strip testing shows no differences in E.T. or mph with the baffles either in or out.

Pictured above is our LSR 2-1, 1 3/4", C Style, turnout part number 00-1167. Twin Cam 88, 95 cubic inch.

The "B's" and "C's". Click on photo to enlarge


A pipe has to look as good as it works and every angle has been considered with the LSR 2-1. The pipe is designed to follow the motor's lines and to provide the necessary ground clearance while still allowing access to oil fillers, ignitions, and push rods. The 3" diameter tail section is available in Turn Out or Slash Cut styles.

Probably our best performing Softail pipe for smaller (under 100") motors is this 00-1163 LSR 2-1, B Style 1 3/4" with a Turn Out tail section in Silver Ceramic.

Customer says "The fit, finish, sound, and performance are great. I get compliments all the time. This pipe replaced an e-series and I couldn't be happier with it! To any potential customers who aren't sure about their decision... I would say go for it. They won't be sorry. Thanks again for your help."

Customer says "Thanks, I am so stoked about these pipes.  For a basic stock motor with some bolt ons, this thing is pulling away from me in every gear.  I spent about six months looking at everyone’s pipes.  I knew I didn’t want just any pipes for the looks.  For the bucks pipes cost, I want the real deal.  So far I think I got it. Can’t wait to get to the corner to sport ‘em."

Here's a chrome version of the 00-1163 with the Turn Out rotated 45 degrees.

Some models which have floorboards can only fit a "C" Style pipe. As to which one works the best there are too many variables for us to discuss as it varies model to model. Some customers have priorities such as extra clearance for their forward contols and their tennis shoes / cowboy boots / high heels / lineman they go for the "C" Style. Other customers demand a "B" style because they "know it's better because they had a "B-Style" on their last bike and it kicked ass!" Everyone has his priorities and the bike set-ups are so different that we offer both styles "B" and "C" as well as 1 3/4" and 2" in both Turn Outs and Slash Cuts for most models. Decisions, decisions, decisions!

Pictured above is an LSR 2-1, C Style, Turn Out, 1 3/4", part number 00-1008 for a Shovelhead.

Pictured above is a TC88 LSR 2-1 Turn Out, C Style 1 3/4", 00-1167. Bike has been run for a year with slight discoloration of the primary tubes. Heat shields were ordered to cover this.

C Style Rotated 45 degrees

Customer writes: " Hi all, Here are the pictures of the LSR 2-1 (1167 C-style) that I installed on my scooter. Looks BAD AS HELL doesn't it. This is the best looking 2 into 1 that I have ever seen, in fact, I'm getting compliments from guys who were just like me, "I wouldn't get caught dead with one of those damn things on my ride", till I found this one on the net. Simply put it's the best looking, best performing, best crafted, and the badest sounding pipe I have ever owned! Hell I even bought the heat shields for it, but I'm not putting them on and covering up this piece of fine craftsmanship, until I absolutely have to. Heck with the quality of the chrome on this pipe they may never get installed."

00-1167 TC88 Softail Turn Out rotated 45 degrees.


People call us up all the time and want to know how how our pipes compare to the "competition"...We usually respond "Fuck if we know!"...Some people get pretty incensed at this response and demand to know why we don't go out and buy other people's designs and "test them". We realize people are impatient in their desire for someone to make a decision for them...we just aren't going to play that game. The magazines are full of ads with pipes that claim to be king of this and that and are otherwise oozing with superlatives. Some manufacturers go so far as to publish dyno charts showing their pipe to be better than Brand "X"...Did you think they were going to otherwise? Comparisons and dyno sheets we would publish would be self serving bullshit. It's a tuner's game and it always has been. We just build parts that don't limit you in this area.

Most of the time the customers do the "comparison" because the average caller already has had somebody else's pipe or pipes and is looking for something better. It's bad science, besides being expensive, to try a bunch of pipes without trying to optimize the tuning each time, and we tell people this. We will tell you, however, that shops that have spent a lot of time trying to wring out a few extra horsepower generally will find our pipes to give them some extra horsepower right off the bat and more once they learn the combinations that work with them. The real answer is that we have well proven designs that don't represent a limit in your quest for horsepower. The pipe is but one element of the equation. Pictured above is an LSR 2-1, C style, part number 00-1060.

Torque and Ruby Slippers

People get pissed at us when they ask for "numbers". We always tell them we "don't know" because after nearly 33 years of tuning and racing and designing we have seen too much and done too much to give any placebo answer. In fact it always depends on the bike and the tuner. No two bikes are alike. Maybe your bike was built on a Monday and they left a coke bottle in the gas tank (old Detroit wive's tale)...Some bikes are faster than others. Everyone believes their bike is "faster". It depends on the tuner and, these days, the bikes are more complicated. People change from chain to gear drives. They put on different cylinder heads. They switch cams. They add on tuning twiddle boxes. They tune, or the "shop" tunes. They "dyno" the bike...maybe even somebody rides the bike with instrumentation like our RSR Air Fuel Ratio Gauge.

People call us up then hang up when we tell them we don't know what their "gains" will be. We don't publish self-serving charts. We just take all the experience we have and build the best parts we can. People end up happy who buy the parts because they are well made and are designed to perform. We make different tube diameters and offer a wide range of systems for any particular bike so you will maximize your potential. There is no "One Size Fits All" at RB Racing.

People who don't buy the parts because we won't coddle them with assurances go elsewhere where Aunt Em will tuck them in and tell them what they want to hear.


For those of you who just love numbers and not science we'll throw some figures at you that customers call up with: 95" 107 Hp; 96" 112.5 Hp; 104" 128 Hp; 107" 138 Hp; 120" 142 Hp; 113" 142 Hp; 117" 138 Hp; 106" 126 Hp (see below); 104" 255Hp (Turbo); 120" 300Hp (Turbo); etc. etc.

Typical Comment: "Though it took awhile to get it, it was worth the wait... Hi to you all at RB Racing this is Tony D. I got my 02 Deuce back from my tuner today ( had him map it ) it has the 95" kit 10.25 pistons SE HP Heads and SE 251 Cams with a Power Commander on it. It Dyno'ed at 87hp with the Vance & Hines Short Shots I had on it. With your "C" Pipe (1167) it now Dynos at a 103hp WHOW !!!!!!! or should I say Holy Fuck-N Shit !!!!!!! What a diffrence the RIGHT PIPE makes ! Though I haven't put very many miles on it yet the 45 mile ride home was a blast to say the least. A BIG THANK YOU to all of you at RB Racing.You had asked me to send a photo I do not have a digital camera so I will have to send a photo by mail please e-mail me the address to send it to. Again THANK YOU !!!"

Pictured above is a LSR 2-1 00-1023 Ceramic Black Sportster exhaust.

If you are a tuner and use your head as well as your heart you will do well with our exhaust systems. We make about 400 part numbers, most in two different primary sizes, and three different finishes to make sure we have the right part for your engine from an 883 Sportster up to a big inch firebreather. One size does not fit all...One design does not work for everything. Serious pipes for serious motors.

Typical Story

One shop built a 95" TC88 Bagger motor for a customer and the customer put on a set of somebody's NASCAR inspired "duals"...The customer was unhappy with the engine saying it just didn't make a lot of power and that "there was nothing wrong with the duals...there's something wrong with the motor!" They slipped on one of our 00-1124 LSR 2-1, Turn Out, 2" primary exhausts that he borrowed off another bike that was in the shop. The bike instantly gained 20 horsepower and 16 foot pounds of torque. Needless to say that ended the discussion about something being wrong with the engine. They ordered two 00-1124 systems with a 45 degree rotation in the Turn Out.

This is the pipe installed on the customer's bike. You can request our LSR 2-1 Turn Out systems be rotated 45 degrees as is the 00-1124 part shown above. The 45 degree rotation is usually where saddle bags are involved. Twenty extra horsepower always makes people happy.

Customer writes: "Pipe performs like a dream bike pulls hard all the way from idle to rev limit its quiet when sneaking home and barks with authority when hot rodding. Fit and finish is excellent ... can't wait for it to show some color, but chroming is so good I might have to wait for awhile. I have tried a great many exhaust systems none compare with yours.I will be using them exclusively .   thank you". Part number 00-1124.

Customer writes "VERY high quality components, with excellent welds and material.  It's clear to see this is not a hacked product, or put together in a shed.  Precision fitments and the components to space out the floorboard and mount the bracket are of equal or better quality than Harley OEM. Impressive!" 00-1122 LSR2-1 Silver Ceramic, 1 3/4" Turn Out rotated 45 degrees.

Customer writes, "Noticable power pull on this pipe vs. my buddie's Road King with the exact same setup other then he's running Rineharts.  No contest on the drag race.  I win handily." 00-1122 Silver Ceramic.

Pictured above is a 00-1145 +5" LSR 2-1; 1 3/4" Slash Cut with three piece heat shields. In general, big inch baggers love the 2" LSR 2-1 exhausts..." I picked up 13.5 Horsepower and 11 foot pounds of torque on my 116" over my V&H Pro Pipe!"...customer from Texas.

Ease of Installation

All LSR 2-1's are constructed in a number of fashions depending on the style of pipe and the model they go on: On rigid mount applications like Softails and most Shovelheads we use a"two-piece" design for "B" and "C" styles. The rear primary tube, the collector, and the tail section are welded into one assembly, while the front primary is a separate piece that slides into a precision "upset" slip joint that is permanently welded into the collector right next to the rear primary tube. This two-piece design makes the pipe supremely easy to install and offers three additional benefits: (1) We get better chroming on the front tube; (2) The slip allows for minor variations in exhaust port heights; (3) The slip joint allows a tension-free final positioning of both the head pipes as well as the tail section in relation to the mounting bracket, thus reducing stress/vibration fractures. There is no cussing when you install an LSR 2-1! On rubber mounted applications that can use "B" style pipes like FXRs and DYNA models we use the same "two piece" design. On rubber mounted applications that use "C" style pipes like FLH/T/Road King as well as certain DYNA and FXR models we use a "three piece" design that adds a second slip joint in the rear primary tube. The shorter rear primary tube is exceptionally rigid and the slip joint removes any stress, preventing fractures in the weld at the collector.

LSR 2-1 Mounting Brackets

Rubber or rigid we have a complete mounting solution for your bike. We see lots of combinations, from stock to offset customs and can provide mounting solutions for most applications. For some pipes like the Shovelheads we give you a piece of steel strap and tell you to fake it. On the Shovels there is a slotted bracket heliarced to the back of the pipe that is just outboard of mounting points on the frame...two quick bends and two holes and you're done.

We offer general LSR 2-1 Mounting Instructions in a PDF Format.

FLH/T/Road King: We supply a laser cut 1/4" steel plate with dowels that bolts to your transmission. The rear of this bracket is slotted and has either two or three bolts that attach the bracket directly to the back side of the pipe. Any oem mounts front and rear have to be removed.

FXR: There are FXRs and then there are aftermarket FXRs like Kenny Boyce frames and a variety of "Rubber Mounted" pro street and quasi-Softail designs. For all of these we provide a 1/4" steel plate that bolts to your transmission. The bracket is slotted to allow for variations in engine mounting and has a selection of dowels that take into account the different transmissions available. The bracket attaches directly to the back of the LSR 2-1 pipe, which has a slotted bracket heliarced to the pipe. The bracket does not interfere with billet aluminum swingarm pivot mounts like those on Kenny Boyce frames or other aftermarket pivot mounts. Pictured above is an LSR 2-1, 1 3/4", C Style, Turn Out on a 1990 FXRS that has made three trips to Sturgis from California.

Softails have a heavy steel bracket that goes from the frame to the back of the exhaust. There is nothing to fracture or break. Pictured above is a 00-1167 LSR 2-1 C Style 1 3/4" Turn Out on a TC88.

Early FXR(P) police models (see above picture with 00-1141 +5" pipe) with floorboards don't fit many pipes. The ex Police bike shown above uses FXR brackets as the rear master cylinder is just outboard of the transmission. Best bet is to install forward controls or mid pegs on this particular model...then regular part numbers apply. To fit LSR 2-1s to these ex Police models with floorboards it will be necessary to cut and modify the rear floorboard support (splined peg mount to floorboard bracket) for clearance on the pipes. FXRT models had mid pegs and pose no problems.

Note: All LSR exhausts require the use of the OEM flanges and circlips. The Harley part numbers for these flanges and clips are: 65328-83 (exhaust ring clamp) and 65325-83A (retaining ring). S&S Cycle SA or B2 (145" Tribute) cylinder heads require four bolt flanges which we provide and are part of the pipe assembly captured by or Special Application Venturis. 00-1180 pictured above.

FXR: Transmission mounted using a laser cut 1/4" steel plate and dowels. 00-1181 (FXR Forward Controls) Pictured above. Customer writes " I am very happy with it. It was easy to install and fit very well. Thank you for a great product."

FLH/FLT/Road King: Transmission mounted. 1/4" laser cut steel plate dowel mounted. No oem mounts are used. Remove oem mounts.

DYNA (Evo): Transmission mounted. 1/4" laser cut steel plate dowel mounted. No oem mounts are used. Remove oem mounts.

DYNA (TC88): Transmission mounted. 1/4" laser cut steel plate dowel mounted. No oem mounts are used. Remove oem mounts.

Softail (All): Pipe bolts directly to frame via 3" wide heavy steel "Z" bracket. No oem mounts are used. Remove oem mounts.

Evo Sportster: Laser cut frame bracket replaces oem bracket (all rigid mount models). On 2004 and later models we supply a transmission bracket that attaches to the mid part of the rear pipe. On 2004 models remove the large oem bracket which requires the removal of the rear final drive cover aft of the transmission. #30 Torx required to unhook rear brake rod.

Mounting Torques

For flanges and mounts we recommend 15 foot pounds of torque. On exhaust flanges you do not use any locking compound as our nuts are self-clinching. On bolts for frame and engine-mounted brackets we recommend that the threads be clean and that a low grade (Blue) thread locking compound be used with 15 foot pounds of torque. Bolts and nuts on our slotted brackets do not require a locking compound but can also be tightened to 15 foot pounds.

In lieu of torque wrenches do not overtighten exhaust flanges to the point where they bend. In the case of bolts going into transmissions and into frames also do not attempt to see how strong you are as aluminum threads and bolts are weaker than you and your wrench are. Simply tighten things till the bolt stops and give another partial turn to firmly snug it. The last bit of tightening actually stretches things a bit and the tension holds things tight. Tightening should always be done in a sequence. Never finally tighten one part then go to the next...Always loosely tighten things in sequence and then finally tighten things in sequence.

The exhaust should never be installed with any of its elements in tension. It has to rest in place without strain and be tigtened without strain.

We employ split lockwashers on most fasteners to prevent counter-rotation. This works surprisingly well if the bolt is properly torqued or tightened.

In any case, you have a responsibility to tighten things or at least check periodically as part of your normal maintenance. Harleys do shake and try to kill anything attached to, or even near them. If things get loose the additional shaking moment can break bolts and destroy threads.

General LSR 2-1 Installation Sequence

1. Remove the OEM exhaust and exhaust bracketry. If the bike has floorboards remove the right floorboard.

2. Pry the OEM exhaust gaskets out of the exhaust ports. We use billet gaskets instead.

3. Install the frame or transmission bracket provided. Use Blue Loctite on the mounting bolt threads into the transmission. Lockwashers under the bolt heads on the transmission mount. If through-bolt like on early rigid Sportsters or Shovels use lockwashers under the hex nuts.

4. Front and Rear primary tubes: Install billet flanges and clips. Install front pipe loosely with billet gasket and nuts provided. Loosely affix the front heat shield to the pipe as you might not be able to install the shield later with the rear pipe in place. We use 1/4 drive ratchet plus extensions and 3/8" socket and a 3/8" wobble for the exhaust stud nuts.

5. If the rear pipe has a slip joint (rubber mounted C Style) slip the rear pipe into the tail section. You may use Permatex ULTRA BLACK.

6. Begin slip of tail section/rear pipe into the front exhaust slip joint (You may use Permatex ULTRA BLACK) and work the rear exhaust and billet gasket into the exhaust port. Loosely affix exhaust stud nuts provided. We use 1/4 drive ratchet plus extensions and 3/8" socket.

7. Slide 5/16" x 18 bolt(s) into slotted bracket on back of exhaust and thread these through the mounting braket. Loosely affix with lock washer(s) and hex nuts provided. Some exhausts may require a spacer (provided) between the exhast slotted bracket and frame/transmission bracket.

8. Gently tighted up all fasteners and nuts. Nothing can be in tension. You may use a rubber mallet to seat the slip joint(s).

9. Install remaining heat shields and tighten front heat shield (5/16" Nut driver). Completely wipe the pipe and shields down with a clean cloth to prevent grease and oil stains from being baked on.

10. Run bike briefly in place. Let it cool down and retighten fasteners. Reinstall the right floorboard with hardware provided.

11. If ceramic finishes it is wise to go through several heat cycles. On modern efi closed loop systems they go into closed loop within minutes. Let bike idle for a few minutes then shut it down to let it cool. Several sessions of this will cure the resins as they are only oven-fired to 400F. Exhaust temperatures are >1000F.

12. Double check all fasteners and ride the bike. Check your work afterwards. You bought a Harley so you are already showing signs of dementia.

Bonneville Proven

 LSR stands for Land Speed Record and that means only one place...The Bonneville Salt Flats, the Great White Dyno. We have the only gas powered street legal bikes over 200 mph and we're damn proud of it. RB Racing doesn't race typewriters, we race motorcycles and when someone says they get a 70% gain from their system, ask them for their 200mph Bonneville Records or any records for that matter. Hell, if we raced typewriters it sure would be a lot easier, not to mention cheaper.

We place an LSR tag on each exhaust system we make so they can be easily identified. Every now and then over the last twenty plus years someone decides to copy one of our designs, usually because some customer is very happy and he "stirs up the pond". They copy the general look but not the features that make them work. The tags eliminate any question about whether it's an RB Racing design or not and allows people admiring your bike to know the pipe's origin.

The tags have proven to be very popular and have been used since 1992. Every now and then someone asks us to not place the tag on their system to which we answer..."send us an affidavit certifying that you have removed all manufacturer logos from your tires, engraved Performance Machine logos from your brakes, Mikuni or S&S identifications from your castings, Harley identifications from your gas tank, Nike logos from your tennis shoes etc. and we'll consider it". The last guy we let talk us out of this was getting his bike in Hot Bike magazine and said he'd give us "credit" for a one off pipe we designed. When the magazine appeared on the newsstand all we saw was "computer designed pipe by Sands Racing". That was the end of that.

New Cloisonne Tags

Like in the adage "The relentless search for perfection" we have upgraded the logos we put on our LSR Exhaust Systems. Previous tags were stamped and formed aluminum with silkscreened details. The new cloisonne tags are a precision die struck brass, nickel plated, with powdered glass fired in an oven then polished to a jewelry finish. These are direct replacements for our older tags and are available for US $25.00 postpaid via US Global Express (foreign) or Priority Mail (domestic US). They come with black headed rivets and are riveted in place with a light coat of high temperature silicone (Permatex 598B) behind the tag. Part # 00-1009.

Customers Race We All Win

Jim Snyder set new speed records with his Sportster. We couldn't get him a Ceramic Black pipe in time so we sent an unfinished pipe so he could make his race. We shipped his Black LSR 2-1 Pipe a few days later. We love racing. It sure beats the hell out of parking and talking. Race bikes, even if they are street bikes always have a drama about them because they have stories to tell.

Turbo Venturis

All RB Racing LSR Exhaust Systems feature our "new" (we've been quietly doing it since 1985!) CNC machined Turbo Venturis that actually "scavenge" to help your motor breathe. Machined from billet, these allow full 2" flow and eliminate the phony restrictions that other 1 3/4" to 2 1/4" pipes have at your exhaust port. We supply special close tolerance aircraft nuts for your exhaust studs because our machined venturis are too wide for a standard hex nut. Pictured above is a Dyna TC88 00-1111 in Black Ceramic.

Performance Built In...Exactly, For Each Application

Our competitors must think you won't notice that they neck their 1 3/4" to 2 1/4" pipes down to as small as 1 1/2" to mate them to your exhaust ports. RB Racing's Turbo Venturis are expertly heliarced to each primary tube eliminating any internal obstuctions and insuring the maximum flow from each exhaust port. RB Racing won't build phony performance pipes...We sure as hell won't ask you to port your heads, put in bigger valves and a high performance camshaft then stick a bunch of stainless steel discs or machined aluminum butt plugs in the pipe to restrict the flow! And we damn sure won't put some silly "1950-ish" reverse megaphone pipe with internal flat plates, baffles and air foils to screw up your performance. Our pipes make anywhere from 6 to 18HP over these stupid designs. From the Turbo-Venturis to the exit of the pipe our pipes outflow all other pipes on the market. Pictured above is a RB Racing LSR 2-1 part number 00-1164 ( 1 3/4" Slash Cut FXSTB Twin Cam Softail in Ceramic Black) being installed at Hal's Harley Davidson's Performance Center.

LSR CNC Machined Gaskets Mandatory

Our CNC machined Turbo Venturis are not compatible with the "bowl-shaped" late model OEM exhaust port gaskets and require early style "flat" gaskets for the LSR Exhaust Systems to both fit and seal properly. The narrow machined flat face of the Turbo Venturi must seat against a flat surface, not the bowl-shaped late model gaskets. Using the LSR Exhausts in combination with the wrong gasket will cause misalignment, inability to tighten the provided close tolerance aircraft nuts, and will force the bowl-shaped gasket into the exhaust port. The correct woven style gaskets to use are: Harley OEM 65324-83 or Drag Specialties DS 174742.

Mandatory for a nominal charge of $9.95 are a pair of our LSR CNC machined gaskets which mate perfectly with our Turbo Venturis. These are proven in over 16 years of use on our race and turbo applications...the only gaskets that will stay in a turbo bike for 25,000 miles! These gaskets prevent any gasket "creep" into the exhaust flow and are one more thing that will give you "an edge" on the competition. We always wondered why people would port their heads, put in bigger valves and then squish the gaskets into their exhaust ports. We bet you never paid attention to what was going inside your exhaust ports for one very simple can't see what's going on in there once the pipe is tightened! The LSR CNC machined gaskets also insure perfect alignment of the exhaust system. Most fitment and alignment problems are traced to using either the wrong type of gasket or using old gaskets that have taken a "set". We've always used these on our race applications and it's time everyone who's concerned about performance should do the same.


All LSR 2 into 1 exhausts require special close tolerance aircraft nuts to bolt the LSR Turbo Venturis to the exhaust port. Standard 5/16" x 24 hex nuts will not fit. Each exhaust comes with the required four nuts. It is recommended that you order an extra set (4) of these nuts, part number 00-1001, when you order your exhaust.

Pictured above is a 1997 Bad Boy with a Black Ceramic 1 3/4" LSR 2-1, B Style, Turnout, part number 00-1054. The ceramic finish has held up for 5 years.

STD Cylinder Heads

We make special flanges for STD heads that match the rectangular bolt pattern that STD machines. If you order a RB Racing LSR 2-1 Exhaust you can order these flanges which have been designed to fit our standard turbo venturis. RB Racing Part Number 00-1003. Sold per pair $29.95. When you order a RB Racing LSR 2-1 Exhaust system we either polish and chrome these or bead blast and ceramic coat them.

S&S Four Bolt SA B1 and  SA B2 Heads

We have been asked by customers to provide LSR 2-1 systems for S&S SA B1 and B2 four bolt heads as well as for the 126" and 145" S&S Tribute engines.  Pictured above are our laser cut flanges and cnc machined venturis that we heliarc to the 2" primary tube for the S&S Racing heads. We make exhausts for both the S&S SA B1 and the S&S SA B2 four bolt cylinder heads with raised ports.

The 145" Tribute engines are 1" taller than stock and have special fixtures.


RB Racing LSR 2-1 exhaust systems use either one or two slip joints depending on the model. We suggest you put a coating of Permatex 598B ULTRA BLACK in the slip joint. None of our slip joints use any clamps because then they wouldn't be slip joints anymore. The inner pipe gets hotter that the outer pipe and they grow into each other and form a tight seal. The 598B is a non hardening gasket material and will prevent any leakage from condensation that forms in the pipe and, with the usual carbon particles, will actually seal better over time. It also makes the pipes easy to take apart later on. Get a tube before you install your RB racing exhaust system.

Custom Made for Your Application

Every LSR Exhaust is custom made for your particular application. Pictured is an LSR 2-1, 2" Style "C", for FXRs with forward controls part number 00-1182. The bike belongs to Dewey Jelen of Deweys Custom Pegs. It is a special construction 120" Merch motor dynoed at 140hp (Superflow CycleDyn) in a Kenny Boyce Frame that has the engine 3/8" offset to left and has a thicker billet nose cone from Jim's...RB Racing builds LSR Exhausts for every damn combination you can think of! We can handle offsets for wider frames and even build "taller" pipes for those applications that have cylinders that may be 3/4" or more taller. When you order an LSR 2-1 from RB Racing we build it custom for your application to insure perfect fit...just be sure to fill us in on all the weird stuff you've concocted. No wire feed bubble gum welds! All LSR Exhausts are fully heliarced for the cleanest possible appearance. It takes five times longer and is much more expensive but it is the best way to do it. All motors are not the same size, so we offer all our exhausts in both 1 3/4" and 2" sizes as well as step header 2 1/2" LSR Nitro Duals...We are the only manufacturer to do this! Your new 100+ inch motor shouldn't be choked off with too small a pipe!

Non Standard Frames

Mais oui mon petit Bourget fabrique en Arizona, tuyeaux partout! When you start building your dream bike things often take an ugly turn when you find out that the only exhaust that will fit your exotic scooter is some serpentine drag / showpipe that is choked down with a couple of 1 1/4" i.d. performance strangling"torque cones"...Then you start looking for a performance pipe and find that everytime you spend your money the new pipe runs smack dab into your extra wide swingarm or master cylinder that your frame maker has conveniently stuck right where the exhaust is normally routed! RB Racing makes LSR 2-1 pipes for Confederates, Bourgets, Kenny Boyce and other frames including choppers so you don't have to get stuck with a set of non-performing pipes that will keep you parked where it's safe instead of at the head of the pack where your dream should be. Keep the paint up and the rubber down and let the mortals hear that motor sing! Pictured is a LSR 2-1 style C Slash Cut w / 2" primaries partnumber 00-1197 for a Bourget Softail.

Big Motor Applications Stock Harley Frames

120 or 131 inch Merch or other big bore motors going into stock Harley Softails, FXRs, or FLH/T chassis can cause all sorts of headaches when it comes to the exhaust department. Some of these motors aren't exact replicas of the Harley V-Twin with different fin structure, fat ass billet oil filters and chunky cam covers and nose cones that are thicker than stock. All these things run into exhaust systems and often the only pipe you can fit is someone's wet dream custom weird cut drag pipes that wouldn't blow the feathers off a duck's ass. Rejoice all you sinners who have joined the "You Can't Beat Cubic Inches" parade to big jugs nirvanna...RB Racing makes a wide range of B and C Style LSR 2-1 pipes to fit all these applications. You might not be reaching for 8000 rpm with the Sportsters but you'll be able to shred your 240 or 250 series donut just fine by 5500rpm and absolutely turn the earth's axis a degree or two right off idle. Just let us know the specifics as to how you've set up your scooter and we'll do the rest. Pictured above is a Titan Gecko with a 107" S&S motor from the Blue Sky state of Montana.

Magnacharger LSR 2-1 Systems

The Magnacharger is a fat supercharger casting that simply doesn't work with all exhaust systems. We have tooled up with eight new pipes for Magnacharger applications...1 3/4" and 2" primary tubes in LSR 2-1 designs, all in our "C" style, somewhat similar to DYNA designs although it is a cross between these and Softail and FL series parts. Check our part numbers page for LSR 2-1, LSR 2-1 Pro Stock. Pictures will be posted as they arrive from installations.

00-1290, LSR 2-1, C Style, in Black Ceramic, Turn Out Rotated 45 degrees on a Dyna FXDWG. Dave runs to the pulsations of the mothership and has plans for a Diesel powered motorcycle. Dave will have us all running on Veggie Oil or at least he will be when the ice bergs melt and we all sprout gills. Dave put a Springer front end on just because someone told him he couldn't. Dave's a Vet....Freedom.

Chrome, Silver , Black Finishes

Bike pictured to the left above is a new Twin Cam 88 Softail with a Chrome LSR 2-1, 1 3/4", Style "B", part number 00-1168. Bike pictured to the right is an Evo Sportster with a Black Ceramic LSR 2-1, 1 3/4", Style "B", part number 00-1022. Chrome or Black: All chrome is full automotive grade duplex nickel, triple plate; Black finishes are a two layer process with an underlying base coat and a semi-gloss black final coat. "Black" pipes are fully polished as if they were to be chromed to remove any surface defects, then are blasted, silver ceramic coated, baked, tumbled, cleaned, shot with black satin and then baked a second time to complete the process. Silver Ceramic pipes are also pre-polished then are blasted, silver ceramic coated, baked, tumbled, and final polished.


On our Dual Coat Black Ceramic LSR 2-1 Exhaust Systems the heat shields and heat shield clamps are ceramic coated with 2000 Degree F satin black ceramic finishes. These finishes resist carb cleaners and other chemicals. Our Silver Ceramic LSR 2-1s use silver ceramic coated heat shield clamps.

Polished Silver Ceramic Finish

If you are running a late model FLH/T Dresser with EFI you might want to consider this finish as they will tend to run hotter than their carbureted bretheren...and discoloration of the chrome can be an issue. The polished silver ceramic will not change color. If you choose one of the 1 3/4" versions, you can get chromed heat shields for the pipes...three piece for the C style, and four piece for the B style pipes. Pictured above is a 2" primary LSR 2-1 C Style, Slash Cut, part number 00-1170, destined for a big inch stroked TC88 Softail.

We've tried everything you can think of and these are the best finishes. Go to our Part Numbers page to check on your application. Pictured above is our new Polished Silver Ceramic finish on a 2" Style C, Slash Cut, part number 00-1170 for a stroked TC88 Softail.

00-1167 TC88 LSR 2-1, C Style, 1 3/4"Turn Out, in Silver Ceramic. Replaced an "E" pipe. More power, better sound, better construction, superior finish...result, one happy camper. Very clean bike with a lot of changes.

New "Dual Coat" Black and Silver Ceramic  Finishes

We have a lot more people looking for durable ceramic finishes and we think we have the best finishes on the market. In the late 70's and early 80's we tried all sorts of coatings and paints and even used porcelain on some of our products in the late 1980's. The newer ceramic finishes are tougher and we use both Polished Silver Ceramic and Ceramic Black to complement our usual chrome offerings. The newest "Dual Coat" Black finish is a double coat process that gives additional protection against scratches and nicks, providing two barriers against corrosion...Silver then Black on top of it.

In 27 years we have tried all sorts of black finishes: Kal Gard, VHT, Techline, and others. We also, in the mid 1980's, even tried porcelain for awhile. It chipped and the heat distorted the parts. Most finishes will not survive over a long period unless they have a base coat to cushion rock strikes, moisture and scratches. The surface has to be perfectly prepared and most applications can fail if run too soon at elevated temperatures as they are typically baked at 450 to 500 deg F whereas the cure takes place at around 750 deg F. Lower temperatures will not cure the resins and they will fail once the bike is run. To get around this dilemma for Black Finishes we have found the best solution is a Silver Ceramic cushion base coat and a secondary Black Semi-Gloss finish on top of this.

"Dual Coat" Black Ceramic finish is the most expensive as it involves a triple process. First the parts are polished to remove any tooling marks.Then the parts are zirconia media blasted to prepare the surface. Then parts are cleaned. The parts are base coated with a Silver Ceramic ceramic base coat and then a second Black coating on top of this.

The Silver Ceramic finishes can be cleaned with soap and water and scuff marks can be removed with Mother's Aluminum and Magnesium Polish.

Dual Coat Black Ceramic Finish

The Dual Coat Black Ceramic is shown here after we media blast the top Black Ceramic Coat off with #100 Oxide leaving the base Silver Ceramic Coat exposed. Holding the blast gun at one spot for a longer period exposes the bare metal underneath.

The Dual Coating process is expensive and takes several days with three trips to the oven. Once to clean the exhaust, once to bake on the Silver Ceramic and a third time to bake on the Black Ceramic Finish. It's the only way a Black Ceramic Finish will hold up to chemicals and corrosion. We have years of experience with this process.

Chrome Shields, Black Shields etc.

1999 Night Train with a 00-1054 in Black ceramic with chrome heat shields.

Las Vegas customer writes: "Dear RB Racing, thank you very much for a wonderful product. It was worth the wait. The flat black ceramic finish and the fit of the pipe just overwhelmed me. I have attached a digital picture of the RB Racing pipe installed on my 2002 H-D FXSTBI Night train and the increased performance of the pipe is great.

I had the H-D Screamin Eagle Racer Tuner software installed and tuned on my bike. The horsepower increased from 83.29 to 104.3 and the torque increased from 87.04 to 104 foot pounds. Once again thanks for a great product. I have several other folks who want to purchase your pipe for their bike."

00-1164 B Style 1 3/4" Slash Cut, ceramic black, TC88, 95c.i..

New Heat Shields for the Collector Area

A new heat shield that covers the collector area is available for LSR 2-1 exhausts. On "B" Style pipes there are four shields: Two on the rear pipe, one on the front pipe and the new shield for the collector area. On "C" Style pipes there are three shields: one on the rear pipe, one on the front pipe and the new shield for the collector area. Pictured above is the new collector shield. All of the shields are hand fitted and have sturdy internal clamp brackets that are helibrazed into place...not spot welded, which would break.

Those of you who want black or silver ceramic coated shields on ceramic pipes we now offer these ... We have been testing these new shields for the last year and have had overwhelmingly positive feed back. The FXR pictured above is a 1 3/4" C Style Turnout in black ceramic with chrome heat shields. The black ceramic will not change color and the chrome shields will continue to look new and prevent any scuffing, not to mention keeping your tennis shoes from melting.

It's the Airflow That Limits Things

RB Racing LSR 2-1 Exhaust systems are now available for S&S Cycle Special Application "SA" and B2 heads with 2 inch diameter primaries. The standard SA exhaust valve is a whopping 1.75" diameter with a special (non standard) exhaust port configuration. The B2 heads have even larger valves.

These are the best production castings going with their raised inlet and exhaust ports. Oh, you can fool around with the usual porting bullshit, but you'll end up where these castings start out in terms of cfm. Progress is progress and year to year the only horsepower gains come when you make the cylinder heads more efficient.

The problem with the SA/B2 heads is that nothing fits their four bolt pattern and the shallow non-standard pocket is decidedly bigger than anything sitting on the shelf...stock flanges need not apply! S&S figures you are going to fab your own exhaust so they provide a machined spigot that slips through the four bolt flange. The idea is that you get some springs and make up a slip joint and go creative...this doesn't work on street chassis.

Compare the oem size exhaust flange on the left that is used on "billet" motors with the "SA" flange on the right...get out your calipers and see what's holding these other motors back. RB Racing is familiar with these four bolt critters as we use them in our 113" RSR Fuel Injected ORCA motors both turbo and normally aspirated. For our 113" ORCA motors we use cnc machined special Turbo Venturis that capture a laser cut four bolt flange and are in turn heliarced to our 2" LSR 2-1 primaries. The Turbo Venturis flow 8 to 12% more than a straight section pipe. We also make LSR Nitro Duals for these heads for those of you who don't want to be seen with a 2-1 at the senior prom.

R&R Billet Heads

Another non-standard exhaust port. R&R billet cylinder heads. 2.125 x .400" deep. We can make custom exhausts for these but it is a special order item only. These are on a 147" R&R motor.

Ducks in a Row

People are really fond of trying to organize everyone in various locations to fit their schedules and project deadlines. Usually RB Racing gets lumped into this chain of events...shows, dyno guys, mechanics, trips, races etc. Well, we just really go on our schedule because there is enough anarchy and angst in the world to go around. Our advice is to start organzing all the other people after you get our exhaust because we just run on our schedule and not everyone else's. Seems to work out best for the majority this way. FIFO.


These days people have all sorts of expectations. They want to be loved. They want to be admired. They don't want their chrome to turn colors. They want "numbers". They want assurances. They want guarantees, warranties, trial periods, and return policies. They don't want the part, they just want everything that goes with their household baggage. It's all part of keeping everything nice and tidy and "best". Fear of rejection. Fear of making any decision.

We just come in and make the best parts we can and that's all there is to it. The rest of the equation is too complicated. There are plenty of people who will assure you till hell freezes over. We don't have time for this.

For those of you who do not understand that 1450 Deg F of exhaust flame front will discolor chrome don't order the parts, or just leave the bike on the trailer..or order the heat shields to cover up the underlying discoloration. Ceramic or chome the pipes get really hot and heat shields provide an air gap to protect and hide things.... Melted tennis shoes, burned pants. Air is the perfect insulator.

It isn't the old days anymore. People with $35,000.00 toys roll up in the screaming fetal position. Joy used to be a basket case that you could get running. Brave new world.


The agony of decision making can drive a poor consumer insane..."What is the best?"...".."How does it compare?"..."What will I get, what will I gain?"..."When can I get it?"..."Should I get a 2" or a 1 3/4" pipe".."Will the chrome blue?"..."Can I talk to someone who has one?"..."How long have you been in business"...""I've never heard of you"... "How black is the black?"..."Why haven't I seen these before?"..."My bike is at the builder and he has to have the pipe by Friday or I lose my slot!"..."Is the silver as shiny as chrome?"..."I have a wazoo998 cam and billet rocker boxes and a 280 rear tire...will your pipe work?"

Right brain, left brain. Fear of rejection. Fear of being different. Social standing. It's all too much for most people to deal with.

Look at the pictures, take the Red Pill, and start your journey. It's that simple.

Remove the Angst

If you wish avoid any decision and stay right where you are, just take the Blue Pill. If the journey for truth and power excites your spirit, take the Red Pill.

No Limp Dick Designs

Ever since Jesse James did his original Hell Bent pipes people have either copied them or tried to make whatever they were doing swoopy. If you are a slave to fashion then these might just suit your fancy. At RB Racing we build logical designs that work and leave the limp dick fashion trend to those who love to park and talk.