Professional Rake and Trail Calculator

[Sandblaster]

Thinking about modifying your offset, fork size, axle size, or wheel size?
Here is a really cool calculator that will help you make the required changes..

http://www.rbracing-rsr.com/advchoppercalc.html

Here is a example of some of the info there:

Your front suspension geometry is defined by the following six variables which are defined as:

Offset-- Centerline of top of steering neck to centerline of top of fork tubes.
Rake-- The angle in degrees of the steering neck from the vertical.
Fork Length-- The distance between the top of the fork tubes to the centerline of the axle.
Diameter of the front tire.
Diameter of the rear tire.
Trail: Distance defined by vertical line from axle to ground and intersect of centerline of steering neck and ground.
Raked Triple Trees-- In order to bring trail figures back into line, triple trees with raked steering stems can be used. Expressed in degrees. Usually adjustable in 3, 5, and 7 degrees of rake.
Tire Diameter Formula: If you do not know a certain tire diameter use the following formula:
Diam Inches = Rim Diam Inches + [ (2 x Aspect Ratio x Section Width) / 25.4]
Example: 200/55R18 Tire:
26.7" = 18 + [(2 x 0.55 x 200)/25.4]