function calcfork() {
	if(document.form1.tirediam.value == "") {
		alert("Please enter a front tire diameter in inches!")
		document.form1.tirediam.focus()
		return false
	}
	if(document.form1.rake.value == "") {
		alert("Please enter your steering head rake in degrees!")
		document.form1.rake.focus()
		return false
	}
	if(document.form1.offset.value == "") {
		alert("Please enter your triple clamp offset value in inches!")
		document.form1.offset.focus()
		return false
	}
	if(document.form1.length1.value == "") {
		alert("Please enter height of steering pivot crown to ground in inches!")
		document.form1.length1.focus()
		return false
	}
	if(document.form1.tripletree.value == "") {
		alert("Please enter triple tree rake in degrees!")
		document.form1.tripletree.focus()
		return false
	}
	
	tempdiam1 = document.form1.tirediam.value
	tempdiam = tempdiam1 / 2
	anglerake = document.form1.rake.value
	angleraker = (anglerake / 180) * Math.PI
	offsetl = document.form1.offset.value
	anglefork = (document.form1.tripletree.value * 1) + (document.form1.rake.value * 1)
	angleforkr = (anglefork / 180) * Math.PI
	l1 = document.form1.length1.value
	l2 = (l1 * 1) - (tempdiam * 1)
	l3 = Math.sin(angleraker) * offsetl
	l4 = (l2 * 1) + (l3 * 1)
	fork = l4 / Math.cos(angleforkr)
	
	l5 = (l1 * 1) * Math.tan(angleraker)
	l6 = offsetl / Math.sin(angleforkr)
	l7 = (l2 * 1) + (l6 * 1)
	l8 = l7 * Math.tan(angleforkr)
	trail = (l5 * 1) - (l8 * 1)
	
	

	test = fork
	tempj = Math.round(test * 100)
	tempk = tempj * .01
	daRatio = parseInt(tempk * 100) / 100 
	document.form1.ratio.value = daRatio
	
	
	test2 = trail
	tempj2 = Math.round(test2 * 100)
	tempk2 = tempj2 * .01
	daRatio2 = parseInt(tempk2 * 100) / 100 
	document.form1.ratio2.value = daRatio2
	
	
}