LSR Pro Stock Challenge"RaceCat" 2-1's

No 1950's megaphones, No Aluminum Butt Plugs

A pure LSR 2-1 Pro Stock Challenge pipe but with some sound attenuation and a RPV Technology Racing Catalytic Converter to knock a few decibels off the normally wide open LSR 2-1 Pro Stock design. This allows you to run a full race LSR 2-1 Pro Stock Challenge system on the street. Not quiet but clean. Here with Dual Coat Black exhaust and full black heat shields.

These use our 12 degree LSR 2-1 Pro Stock Merge Collector. Keeping the same dimensions as our Challenge systems we have added a custom zero restriction catalytic converter that has a much higher bypass are than the 2.5" tail section of our Pro Stock Design and added a baffle after the catalytic coverter. This cleans up the exhaust and makes the pure racing pipe a tad more acceptable on the street. Wide open it still wails but idle to part throttle operation is mellowed a bit.

We custom hand make these as they are very expensive and labor intensive. They are only sold with Dual Coat Black or Silver Ceramic exhausts and a full four or five piece heat shield set including the complex heat shields that cover the collector, the tail section, and the primary tubes. Shield pricing follows our standard pricing depending on the finish. Shields can be in Chrome, Black Ceramic or Silver Ceramic.

We give you the choice separately on pipe and shield pricing i.e. some people may want full chrome heat shields and others may want a Black Ceramic or Silver finishes. It's your choice as to the aesthetics of the selection.

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.

The designs have been tested on our 80" FXR, a SE120R 135 hp Road Glide and a 110" CVO Road Glide. All part numbers are 00-1306-RC and are custom made for each application. Costs for the base system adds $300.00 to our published LSR 2-1 Pro Stock Challenge prices. Systems can be made in both 1 3/4" and 2" primaries. We build to order. Payment at time of shipment. Systems are delivered in ceramic finishes...Dual Coat Black or Silver.

Exhaust above is a 2" 00-1306-RC  LSR 2-1 Pro Stock RaceCat in Dual Coat Black Ceramic with four chrome heat shields.

The 110" CVO Road Glide uses our Dual RSR Air Fuel Ratio Gauge to monitor the front and rear cylinders in real time and TTS MasterTune software to make VE adjustments for front and rear cylinders. Real World Tuning.

On FLH/T models the 00-1306RC exhausts extend to the end of the bags like our LSR 2-1 Black Hole and Pro Stock Spyder systems do.  It's not as loud as a completely open LSR 2-1 Pro Stock system or our LSR 2-1 Pro Stock Spyder. Fries the back tire with SE Race Clutch and hydraulic master cylinder.

Milwaukee 8

People keep asking about RB Racing releasing LSR 2-1 exhaust systems for the new Harley Motor. Well, we are fixtured for them with a new muffler design that takes into account the increased compression and displacement, but we are not releasing anything until some things settle down. No matter what people say, this is an emissions-designed engine with a lot of compression, locked in place valve adjustment and camshafts that are simply going to give you next to zero in gains for your hard earned money in changing the exhaust. Every exhaust manufacturer wants your $$$. We don't. We'll release them when there are real gains to be made.

Testing has shown cam changes need to be made along with a 2-1 exhaust to make any appreciable gains. Go ahead buy your $500.00 air cleaners and your $700.00 Monster Slip-Ons...keep the economy going.

It's still an air-cooled 45 degree V-Twin no matter what they say about water or oil cooling. BTUs are BTUs...It just has less flexibility in terms of modification than EVOs or Twin Cams at this time.  Another expensive puzzle. Not yet.

People tend to forget these are heavy couches. Adding weight is a no no. One of our M-8 test bikes came in with a V&H Duals that, when we removed them, weighed 41 pounds!! Our M-8 exhaust weight far less than Half of that and the Pro Stocks 1/3 of that. Power to weight ratio. Heavy couches.

The Milwaukee-8 is a taller, heavier engine with the O2 sensors moved upstream, closer to where they should have been. Earlier LSR 2-1 designs will not fit this motor. We supply a different saddlebag mount system for our under the bag designs like the Pro Stock Spyder and Black Hole. All systems also have a three point laser-cut mount off of the transmission.

00-1396 LSR 2-1 Pro Stock Spyder exhaust with 2" primaries and four heat shields.above.

Milwaukee 8 Exhausts: 12mm and 18mm O2 Sensor Ports Standard

All LSR 2-1 Milwaukee 8 Exhausts come standard with both 12mm and 18mm O2 ports. This gives customers the choice to run either the OEM 12mm or 18mm O2 ports (or both with our RSR Air Dual Fuel Ratio Gauges) and tune with various narrowband or wideband options on the market.

If you are running a Tuner that disconnects the 12mm or 18mm Oxygen Sensors with "O2 Optimizers", putting your bike into Full-Time Open Loop, then you should order our RSR Dual Air Fuel Ratio Gauge.

When you order the Gauge, for real-time, as you ride, monitoring for tuning purposes, we provide you the specialized harness plugs and wiring to connect your OEM O2 Sensors to our RSR Dual Air Fuel Ratio Gauge. It's the proven way to perfect your fueling.

Single orDual RSR Air Fuel Ratio Gauge: 18mm or Late Model (12mm) O2 Sensors


Dual RSR O2 Gauge: 06-1003 Compatible with OEM 18mm O2 Sensors. If 12mm OEM Mini-Switching narrowband sensors this gauge reads secondary 18mm O2 sensors.
Real world tuning while you ride...Observe and then make adjustments. Mounted permanently. Waterproof.

Single RSR O2 Gauge: For carbureted models. 06-1005 Kit

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).

Pro Stock Power... Noise reduction, Zero restriction, Clean Quiet exhaust

Unrestricted LSR 2-1 Pro Stock power with noise reduction featuring a Zero-Restriction RPV Technology catalytic converter to make the world a greener place while you are shredding your tire and burning rich mixtures to please the OPEC Sheiks...without the noise.

Our RPV Racing converters are rated at about 450 CFM i.e. 300hp flow rate.

Big Inch Engines: SE120R, 124",126", 143" S&S... "Race Cat" ready

The SE120R Engine was originally for Baggers and a specific AHDRA racing class...another way for the MOCO to get your money now that V-Rod Destroyers are old news. Think of all the early adopters who went 95/103/110 and now they can go 120". Stimulus money! If you want one in your bagger and want a full race system then our LSR 2-1 Pro Stock "RaceCat" is about the only way you can get your peak power and have some sound attenuation. Ride your bike to the racetrack. 850 lb race bikes...get real.

135 claimed hp is nice but the noise gets old...unless you only want to run your sled on a dyno. In the real world the man is waiting for you. And you can opt for a set of SE Hurricane heads and maybe eek out 150 Hp and make even more noise.

If you are a Horsepower Freak then the LSR 2-1 Pro Stock "Race Cat" is your ticket to semi-respectability...You can claim you are "Green" because of the Catalytic Converter when you kick their ass. The socially acceptable method of achieving dominance in the "my dyno report is bigger than your dyno report" world.

As all the mythical lemmings head off the cliff we might remind them that a S&S SA B2 126" engine is rated at 154 hp and John O'Keefe at Branch O'Keefe has been working SA B2 heads for big inch Sportsters, S&S 124" motors and getting 166 to 200 hp depending on compression. Of course you could get one of our turbos but the extra 100 to 200 hp might be too much power for you...Turbos chop up the exhaust noise and don't need a muffler...Going fast without all the noise is a lot more fun.

S&S T143 with B3 Heads..Even bigger and $$$$

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 integral B3 flanges. The exhaust port dimensions are not oem, not S&S SA B1 nor S&S SA B2. Go figure.

We have made custom parts for these T143 B3 ports. Available for the five product ranges we manufacture...Quiet (LSR 2-1 Black Hole) to Full Race (LSR 2-1 Pro Stock). The new two bolt/stud LSR 2-1 B3 Flange is integral, free rotating to the exhaust port. Full 2" I.D. No billet aluminum Butt Plugs or packing you have to replace.

Belts won't last on these 143T motors so we offer chain drive/swingarm conversions for 09 and later Baggers...Developed for our 360 Horsepower turbos.

Bye bye men in blue

The highway is for gamblers, better use your sense. The blacktop, too, is moving under you. Yonder stands the man in blue.. all ears and waiting for you. All your straight pipe friends are coming for the man in blue. Free tickets for the courtroom door... Twist the grip and start anew, the man won't be stopping you. RaceCats pass straight on through. Your friends will meet the man in blue, but the road ahead calls out for you. And it's all over now for the men in blue.

Pro Stock power...Pro Stock LSR 2-1 "Race Cat" with noise and emission reduction.

3X is the solution

Until RB Racing attacked the problem noise was equated with power.  A number of years ago we introduced our silent running LSR 2-1 Black Hole systems that produced power without getting tickets or wearing out your welcome or your passengers on long rides.

We then came out with our highly successful sound-cancelling LSR 2-1 Pro Stock Spyder systems for people who modified their engines for more power and displacement but still wanted a pure race system but with some sound reduction....and just enough sound reduction to make touring and sport riding tolerable.

At other end of the market were the power junkies who had to have our pure racing, championship winning, LSR 2-1 Pro Stock and Pro Stock Challenge systems. People kept asking us to put baffles in our Pro Stock systems and we kept telling them "It would kill the power....So don't do it!". You simply can't cram a baffle into a tuned 2.5" (63.5mm) tail section without choking off the flow. Houston we have a problem.

Our answer was to cut the noise a bit with absolutely no restriction and clean up that rich power producing mixture on the way out... Might as well swing for the fences.  The only way was to increase the cross-sectional area and have a bypass mechanism that attentuated the sound by slowing the gases and then speeding them up as they exit. The answer was to use a custom design a high bypass RPV Technology catalytic converter core that has three times (3x) the flow rate of our LSR 2-1 Pro Stock 2.5" tail section. The sound is dissipated and the spent exhaust gases are cleaned in the larger cross section then speeded up in the 2.5" exit. Zero restriction followed by a muffler coretodampen the pulses.

The LSR 2-1 Pro Stock "Race Cat" allows you to run a full race Pro Stock System on the street. It's not a sound cancelling system like our LSR 2-1 Black Hole or our LSR 2-1 Pro Stock Spyders but it is the highest tech, clean catalytic solution for built engines.

Branch O'Keefe Ported Heads

John O'Keefe of Branch O'Keefe has larger displacement kits for late model Twin Cam engines. Stock  engines from Harley are way down in horsepower. This doesn't cut it with an 800 lb sled. Typical Branch Specifications: Larger inlet and exhaust valves; .060" decked cylinder head; compression releases; new valve guides; racing valve springs; flowed inlet and exhaust ports; forged lightweight pistons contoured to match quench style combustion chamber; and BP-600 Branch camshafts. Not a bad idea to get a matched, proven, combination.

CNC porting is fine but has two limitations: (1) Core shifts in the casting process often means the ball end cutters in 5 axis operations can skip surfaces which really should require additional hand finishing that is often not done; (2) Each motor is a bit unique i.e. port velocity at a given rpm is so important for a particular situation that canned port work tends to be a generic one shot deal. F1 engines are still hand finished even after cnc preparation.

John does all our race stuff and has since 1977. Marry these with a LSR 2-1 Pro Stock "Race Cat" and you have a killer combination. He'll set up you heads based on about 100 years of his and Jerry Branch's research.

Hand Made Pro Stock Merge Collector

From exhaust port to the collector area this is a pure LSR 2-1 Pro Stock exhaust system for the highest velocity and peak scavenging at the exhaust valve. We mate this to our zero-restriction, noise-reducing LSR 2-1 "RaceCat" technology.  The twelve degree knife edge merge is the best flowing collector on the market, pure race technology...All precision heliarced, not the abrupt, wire-welded, collectors the mass production houses use.

Silver and Black Ceramic Finishes

In case you are interested, here's the drill we follow for ceramic coating. Bend the parts. Pattern cut the parts. Deburr and polish the sub parts. Tig weld and hand fit the merge collector. Tig weld the assemblies in sub fixtures. Drive the parts to the coater. Coater bakes the parts, then cleans the parts to remove any internal residue.  Coater then masks and sprays the parts with silver ceramic and bakes the parts for a second time. Coater then tumbles the parts in large vats to burnish (harden) the surface. Then the parts are final polished by hand.

In the case of Black Ceramic it is a dual-coat process: Coater bakes the parts, then cleans the parts to remove any internal residue.  Coater then masks and sprays the parts with silver ceramic and bakes the parts for a second time. The next day black ceramic sprayed on top of the silver and the exhaust is baked for a third time.


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.

Nightmare After X-Mas

TV, Jesse James, Orange County Choppers, biker build-offs, master builders. Art is cool but when the cold winds of reality blow you get back in your pickup truck. No way to make a fashion statement quiet enough to avoid tickets and get you where you want to go. Great for the short putt to the bar or HOG meeting where you can bask in the glow of your "I saw it on the Discovery Channel and now I have one". We like art and sculpture and Dali would approve of the drooping exhausts but that's not why we build things. Noise, loss of torque, tickets...well, we make pure race pipes and will give you back your torque if you'll take take the the other two with it.

LSR 2-1 Pro Stock "RaceCat" systems offer an alternative. Power and performance with an acceptable amount of noise. We try to factor in art as we are violently opposed to ugly. Beauty as they say is in the eye of the beholder.

True Duals and Aluminum Butt Plugs

Customers ask us why we don't make "True Duals". While the name has a certain ring to it, with "True" sort of impugning everything else you might consider. Well, we won't make things that don't work, like dual pipes, dual pipes with aluminum butt plugs, or even a falsie left pipe that does nothing. Now, we like Fishtails, and all sorts of things like that which are traditional and pretty. We just aren't going to make them.

Customer writes: " Hello RB Racing !  Just wanted to drop you a note to say THANK YOU, THANK YOU, THANK YOU!!!  I changed the pipe on my Roadking from a popular name brand "TRUE DUAL" to your LSR 2-1. Had the bike dyno'd yesterday and what a difference, The HP number jumped from 82 HP to 89.95 (call it 90) and the torque number jumped from 96 ft lbs to 102 ft lbs.  Nothing else was changed but the pipe.  Anyone know some one looking for a set of used true duals?  While those numbers aren't huge or record setting they are much, much better. In addition, the bike runs tons better, no more cracks or pops and runs smooth as ever at RPM. Again , I can't thank you enough for producing a product that meets the need and not necessarily a product that boasts bragging rights that are unsubstantiated. Mike".

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. Black Hole technology does not involve stupid eye candy, or outdated, or just pain dumb, ginger bread.

New Dual O2 Meters

For OEM Weber/Delphi EFi sequential injection our new RSR Dual Air Fuel Gauge displays the fuel mixture in both the front and rear cylinders separately. 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.

Scale is, left to right, lean to rich: three greens, three yellows, two orange and two red l.e.d.s.

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.

Compatible with OEM narrowband sensors. Can be supplied with new high temperature Bosch narrowband sensors. Far right photo shows gauge in dim light conditions at maximum power setting.

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.

A few years ago 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.

Harley had to recall these after being fined. They are no longer available.

System Approach to Tuning

1. LSR 2-1 Exhaust... Proven performance gains.

2. RSR Air Fuel Ratio Gauge...Observe in the real world. Dynos are great but we don't ride them.

3. TTS MasterTune Software... Make adjustments based on observations

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.

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.


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.


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.

Fuel Injection..A Reality Check

OEM Harley Delphi 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 Pulse width Calculator.

To see what lengths we go to to control 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.

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.

RSR Air Fuel Ratio Gauges...Real World Tuning

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.

Single RSR O2 Gauge: Reads the front cylinder in non-efi models. It is simply the best way to evaluate the tune of your motorcycle and saves expensive and often inaccurate dyno time. Real world tuning while you ride...Observe and then make adjustments. Mounted permanently. Waterproof.

Dual RSR O2 Gauge: Compatible with OEM narrowband sensors. For non-closed loop models (1999-2007) we can supply the LSR 2-1 exhaust with two 18mm O2 sensor ports and two high temperature Bosch O2 sensors: Part Number 06-1026. Real world tuning while you ride...Observe and then make adjustments. Mounted permanently. Waterproof. Use TTS Master Tune Software to adjust the VE tables for the front and rear cylinders.

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.

Tune in the Real World: RSR Air Fuel Ratio Gauge

Since we have been doing closed loop fuel injection systems for Harleys for more than 30 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.

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 glance, while you are dodging cars watching for cops. We have a Superflow CycleDyn which gives a better real world correlation than other dynamometers but we still evaluate air fuel ratios when riding.

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.

 Customer Comments

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.

Digital Gear Indicator and Dual Air Fuel Ratio Gauges

A useless air temperature gauge and tiny warning lights...whatever happened to black and white gauges? Well our RSR Bonneville Digital Gear Indicator and our Dual Air Fuel Ratio monitor actually do provide useful, easy to read, information. Knowing what gear you are in and what your engine is actually doing in front and rear cylinders is a lot more important than knowing what the air temperature is...After all, you are sitting directly in the airstream so the air temperature is no mystery.

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.

O-Sensor Ports Standard

For the last 27 years all RB Racing LSR exhaust systems have come standard with a machined and heliarced oxygen sensor boss just below your front exhaust port. This port is designed to accept and oxygen sensor (18mm x 1.5mm) which will allow you to use our RSR Air/Fuel Ratio Meter to tune and monitor in real-time your air/fuel ratio. Also, if you really wish to get 55mpg and kick ass, our RSR Fuel Injection's closed-loop heated O-Sensor will plug directly into this port.

All newer closed loop Delphi EFI Harleys use two O2 ports, either 18mm or in newer bikes 12mm. When ordering your LSR 2-1 Pro Stock "RaceCat" we need to know the year and model to install the correct ports. If you have a newer model and plan on using 18mm "Wide-Band" sensors these can be installed.  For some customers we install both the 12mm and the 18mm O2 ports. There is no charge for adding or substituting O2 ports.

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. 800 hp 2-1 Top Fuel exhaust pictured with 214 mph in 1/4 mile results. Carl and Lesa Pelletier of Competition Motorcycles.


LSR 2-1's Bonneville, Dyno &Track Proven

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!

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. The base map must be designed for additive correction except at wide open throttle.

OEM Harley systems have a 15% correction ability. The trick is not that it adjusts...which it should, but that the underlying base map is correct for the changes you have made and then the system can correct within this 15% window.

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.

You 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. The knowledge is still there and the experiences were invaluable (not really) but carbs are a dead issue these days.

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. Stock 4 speed Harleys in the 12's at 103 mph, stock 2 valve 550's into the 11's, early 750's into the 10's and the first stock 1100's into the 9's. Does it mean anything now? Nope.

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. It isn't going to work.

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.

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.

We sort of understand efi

For the last 18 years 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 we use Cosworth Pectel Controllers

We like FXR's. This is our late model CVO that we changed a bit. We use it for testing exhausts like the new LSR 2-1 Pro Stock "RaceCat". We put our RSR Closed Loop Fuel Injection on it...It's still just an 80" Evo. We got rid of the 21" front and put on early style mags with a 19" front. The belt drive was removed and put on a 530 rear chain. To cover more ground we put on a 5 gallon FLHX gas tank.

We have torn this poor FXR apart again for its next incarnation.

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 all evolved into the same formula we decided on 18 years ago. Single large throttle body, in our case 56mm RSR EFI, port injection, and closed loop operation with idle air control. It's not any simpler. In fact the whole deal has gotten a lot more complex.

On all or new applications we use Pectel Cosworth ECMs with Fly-By-Wire or throttle by wire inlet systems.

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.

LSR 2-1 Pro Stock "RaceCat" Mounting Brackets

Note: All LSR exhausts require the use of the early style chrome die cast OEM flanges and circlips. RB Racing chromed billet flanges and clips are part number 00-1002 for one complete set. The Harley die cast 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 our Special Application Venturies.

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.

Early FXR(P) police models with floorboards don't fit many pipes. 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.

FLH/FLT/Road King : Dual mount: transmission and saddlebag. 1/4" laser cut steel plate dowel mounted to transmission. Oem rear saddle bag mount are used. Remove any oem brackets for the front pipe beneath the nose cone. If you are running a Baker 6 speed they are wider and we have to shorten the transmission mounts by 1/2".

DYNA (Evo) : Transmission mounted. 1/4" laser cut steel plate dowel mounted. No oem brackets are used. Remove any oem brackets. 00-1281 2" C Style for a 145" S&S Tribute motor pictured.

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

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

Evo Sportster: Laser Cut steel bracket replaces oem bracket (all rigid mount models). On rubber mounted models we supply a transmission bracket that attaches to the steel stamping that supported the mid part of the rear pipe. On these 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. 2004 Rubber mounted engines require early style exhaust flanges as the 2004 flanges are too thick for our turbo venturies.

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.

The technology we use with our turbos equally applies to our exhaust systems. Turbos don't make more power with excessive exhaust backpressure and normally aspirated exhausts don't like restrictive mufflers either. These are just antiquated 100 year old air compressors and they need all the help they can get.

New Cloisonne Tags

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.

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.

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 Venturies 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 18 Hp over these stupid designs. From the Turbo-Venturies to the exit of the pipe our pipes outflow all other pipes on the market.

For those of you who bought the slip in "torque cones"....Throw them in the trash.

LSR CNC Machined Billet 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.

Customers have asked us to include our billet gaskets with each LSR exhaust system as it is a hassle to search for the correct flat woven, early style gaskets and they cost the same as our superior billet gaskets.

Mandatory for a nominal charge of $9.95 are a pair of our LSR CNC machined gaskets which mate perfectly with our Turbo Venturies. 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.


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.


All LSR 2 into 1 exhausts require special close tolerance aircraft nuts to bolt the LSR Turbo Venturies 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. The exception to this is the four bolt "SA" and B-2 flanges on the S&S Special Application cylinder heads which use Allen bolts.

Chrome, Black, Silver Finish

Chrome, Duak Coat Black Ceramic,  or Silver Ceramic: All chrome is full automotive grade duplex nickel, triple plate; Dual Coat Black Ceramic finishes have a semi-gloss black look. Silver Ceramic finishes have a polished surface finish. Black, Silver Ceramic pipes are fully polished as if they were to be chromed to remove any surface defects, then are blasted, and finally ceramic coated.

Ceramic finishes hold the heat in the exhaust better than does chrome. Chrome has the hardest surface finish. Ceramics do not change color. Ceramics can scuff or marr if hard, sharp objects scratch them. Heat shields for the primary tubes and collector area are recommended for all applications to prevent any contact with the pipe's surface.

Newer 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, Semi-Gloss Black, and SS Titanium to complement our usual chrome offerings. The newest "Dual Coat" Black finishes are a dual coat process that gives additional protection against scratches and nicks, providing two barriers against corrosion.

In 27 years we have tried all sorts of black finishes: Kal Gard, VHT, Techline, and others. We also in the mid 1980's we 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 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 we have found the best solution is a 2500 Deg F Ceramic cushion base coat and a secondary Black Semi-Gloss finish on top of this.

"Dual Coat" Black Ceramic finishes are therefore the most expensive as they involve 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 2500 Deg F ceramic and baked. After this process they are tumbled to burnish or harden the surface.

If the parts are to be Black are first lightly abraded and then are sprayed with a second ultra high temperature coating and baked a second time. The 2500 Deg F base or cushion coat adheres to the metal very well and provides insulation and corrosion protection. The black is a thinner coat and provides the smooth, dark black, finish we require.

The Semi-Gloss finishes can be cleaned with soap and water and scuff marks can be removed with Mother's Aluminum and Magnesium Polish.

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

Heat Shields for LSR Pro Stock "RaceCat" 2-1 Exhausts

On "C" Style pipes there are three shields: one on the rear pipe, one on the front pipe, and one for the collector area to the converter.

On "B" Style pipes there are five shields: Two on the rear pipe, one on the front pipe, and one for the collector area and one for the tail section.

All LSR 2-1 Pro Stock "RaceCat" Exhausts have a heat shield (mandatory) on the collector to the catalytic converter section. This is where the exhaust energy is dissipated to muffle the sound. Cancelled energy generates or traps heat. If you are running at elevated RPMs under load for extended periods there can be some discoloration of the chrome in this area. The shield provides a heat barrier and decorative cover for this section of the muffler. We will insist you order the front and rear shields.

All primary tube and collector shields are hand-fitted and have sturdy internal clamp brackets that are helibrazed into place...not spot welded, which would break.

Dual Coat black , or silver ceramic coated shields are available for extra cost. Heat shields are generally done in chrome. The chrome surface resists scuffing.

It's the Airflow That Limits Things

RB Racing LSR 2-1 Pro Stock "RaceCat" Exhaust systems are now available for S&S Cycle Special Application "SA" B-1 and B-2 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. Newer B-2 heads employ 1.800" exhaust 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 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.

S&S B2 Head Porting

Whenever we do something serious like our 139" Bonneville ORCA motor we defer to the experts, especially when we are dealing with raw, unfinished ports the size of a dime. Branch O'Keefe is simply the best in the business and even Jerry Branch (retired) got involved in the decision making. Take a look at some S&S SA B2 ports that about 90 years cummulative experience came up with. All John O'Keefe and Jerry Branch asked was what we thought the exhaust ports should be like in terms of flow based on our 30 years of turbocharger experience. We all agreed on a number and this is what the result was. Ports for 400+ horsepower.

John has worked extensively with the S&S SA B2 heads, winning the S&S 50th Anniversary Horsepower shoot out contest. Normally aspirated B2 ported heads don't look like ours but John knows how to squeeze 200+ horsepower out of them.

John O"Keefe

If you want the best cylinder head work for your Twin Cam 88/95/103/110 etc., Evo, or even Shovelhead contact Branch O'Keefe. That's what we do and have done since 1976 when Jerry Branch prepared our cylinder heads for the 24 hour Endurance racers we built and took to the 1977 Bol D'Or in France. John O'Keefe knows you don't want "down time" so he has an exchange program for cylinder heads. Harley has made a lot of changes in their castings and it's best to go with Branch O'Keefe as differences in machining, alloys, and specifications can cause problems if you deal with porters who don't have the inventory and the experience.

We discussed our Bonneville Bullett project with John and he promptly drug out two sets of S&S SA B2 heads that he had done extensive R&D on. He had the numbers so he was the best guy for the job.

John does not have "homing pigeons" like other outfits where seats come loose, the work is sloppy, or cheap valves that stick or gall are installed. He treats every head they produce as if it was his own. Sort of rare these days.

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. Turbo venturis have also been machined for the large port, 4 bolt flange, S&S "SA" and newer B-2 heads.

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" and 132" RSR Fuel Injected ORCA motors both turbo and normally aspirated. For our 113" and 132" 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.

S&S SA B1 and B2 heads

If you have a set of these "SA or B-2 Heads" and want a specific exhaust be sure to tell us at the time of your order. Adding an "SA" suffix to a listed part number will do the job. Remember they are only avaiable for LSR 2" primary designs. No gaskets are used with these. The special Venturi rides directly against the cylinder head.

S.T.D. Flanges for LSR 2-1 Exhausts

Dating way, way, back S.T.D. put four bolt or stud loctions in their cylinder heads. Lately they have been selling complete engines so we decided to make up some Four Bolt Flanges for our LSR 2-1 Turbo Venturis. These are available at the time you order your system for $29.95 per set in a chrome finish. Billet gaskets required for standard dimension (Non S&S SA) ports.

Purpose Built...No True Dual or Thunder Crap

RB Racing flat-ass doesn't build things that don't work. There is a beauty in things that work well for their intended use and no one design is right for everybody. We build LSR 2-1 exhausts in both 1 3/4" and 2" varieties for everything from a stock EVO or TC88 right up to whatever big inch custom you can think of, including limited production Confederates, Bourgets and other aftermarket chassis.

The LSR 2-1 Pro Stock "RaceCat" fills another need...the need to have performance without having to run a wide open pipe. There is beauty in purpose and, like the yacht or the plane,..."If it looks right it is right". These are right. The "Cat" cleans up the exhaust.

The record setting bagger pictured above ran one of our LSR 2-1 Pro Stock Challenge you can get this kind of power with some noise reduction and a catalytic scrubbed exhaust to boot. Isn't science wonderful. Who says innovation is dead? We never give up innovating.