Further Trail Modification Question

by Bike Builder

under what conditions might you have to modify the axle plates to maintaining proper trail? (If that is required, what are the critical points to use for judging that need and how might one go about setting up check points to maintain accuracy?)

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Aug 19, 2013
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rake
by: mike brantley

What about addressing rake and trail on telescoping down tubes.

Apr 05, 2012
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? On what size forks should I use
by: Anonymous

Hello I have a war eagle frame with a 47 degree rake like to know what size forks to use and what degree Should be in the triple tree

Jun 04, 2011
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Rake and Trail Calculator
by: bikerart

Here is the easiest way I have found to do rake and trail.

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

This is the more advanced calculator,

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

It does not get easier than this, in my book.

Bikerart

Nov 30, 2010
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The Trail Is Determined By Drawing A Vertical Line...
by: Custom Choppers Guide

The Trail is determined by drawing a vertical line down from the center of the front wheel and a line following the rake angle of the frame. The axle plate can be used to adjust the location of the front wheel's center. By adjusting this point forward or rearward the trail will grow or shrink. The trail must be positive as shown in the attached sketch. Negative trail is dangerous and will result in poor handling at high speeds and will result in the bike flopping and will cause severe injury or death. Minimum of 3" of trail is required.

Using a piece of kite string you can easily tape to the appropriate locations and make rough measurements of the rake and trail. Be sure to measure rake and extend line from the frame's neck, not the fork's T. The frame's neck is the pivot point that will determine the trail. Also be sure to measure vertically down from the center of the front wheel, not the axle plate pin or attachment point to the fork. Feel free to let us know with questions. Also feel free to send a photo of your bike from the side view and we can do a rough measurement for you if you are having trouble.

The only conditions you'd have to modify the axle plate in order to maintain proper trail would be if you have an extreme rake angle or a triple T that is not parallel to the rake angle. These are special cases and the Noor1 springer fork plans is parallel to the rake angle.