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Calculating trail from other measurements?

Old 07-16-12, 12:50 PM
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Calculating trail from other measurements?

Everyone,

Can somebody tell me if there's a formula to calculate trail if you know the head angle, the fork offset, and the actual wheel/tire diameter? It seems there should be, but I haven't found a reference.


Thanks . . .
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Old 07-16-12, 01:19 PM
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https://yojimg.net/bike/web_tools/trailcalc.php
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Old 07-16-12, 01:33 PM
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Originally Posted by Jonathan Hanson
Everyone,

Can somebody tell me if there's a formula to calculate trail if you know the head angle, the fork offset, and the actual wheel/tire diameter? It seems there should be, but I haven't found a reference.


Thanks . . .
You're kidding - did you not try Google? calculate bicycle trail
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Old 07-16-12, 02:52 PM
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Actually I can't believe I didn't Google it first either - thanks for the replies.
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Old 07-16-12, 03:14 PM
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Straight edge and a tape measure on the ground?
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Old 07-16-12, 06:23 PM
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Originally Posted by fietsbob
Straight edge and a tape measure on the ground?
It's difficult to accurately project the line through the center of the headtube to make a direct measurement. If you know the published HTA, fork rake and wheel radius, the calculation is easier than trying to measure it.
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Old 07-16-12, 07:39 PM
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Originally Posted by Jonathan Hanson
Actually I can't believe I didn't Google it first either - thanks for the replies.
Proof BikeForums is more respected than Google
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Old 07-23-12, 07:18 AM
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Proof BikeForums is more respected than Google.
Exactly!

Turns out my old Sekai is a mid-trail design.
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