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Old 10-04-2012, 06:37 AM   #14
SS Blowhard
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Joined: Oct 2008
Location: Gold Coast
Oddometer: 2,708
Originally Posted by Clay Spinner View Post
Wanted to bump this... Wondering what length (eye to eye) shock people are using on their 100mm extended swingarms.
Try standard length.

Maintain the std distance between swingarm pivot and lower shock mount
Reinforce the frame at the swing arm pivot and the upper shock mount
The cantilever effect of a "central" lower pivot attempts to increase the
distance between the swing arm pivot and the top shock mount.
Eventually it will.

With the same spring as you used before the extension the ride hight of the extended setup will be the same

Zero Sum.

Increasing the spring rate and / or preload will raise the ride hight.
Experiment with preload to get the ride hight you require and use that to calculate a more optimum spring rate.

This takes the trigonomertry out of the equations and reduces the process to low tech scantling on linear values.

If it doesn't work out all you've invested in is a spring.
Once you get in the ball park you can refine shock length , ride hight, spring rate & mount positions.

Have fun.
My bike is slow but the earth is patient.
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