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Old 09-23-18, 08:55 PM
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Originally Posted by mstateglfr View Post
how is this claim still going on?
a curved fork does not absorb more vibration.
a curved fork and straight fork with the same rake will feel the same. Both will absorb the same vibration and spring the same amount.

further, the wall thickness of the blades is quite important. A 1mm blade under a 125# rider is excessive and would feel harsh compared to a .8mm blade, and thats regardless of if its straight or curved.

as has been mentioned too, tire width and pressure play a big role on vibration damping.

This is coming from well experienced and respected builders. Sachs. Llewellyn. Colnago. Grant Peterson of all people even acknowledges the spring and damping of a curved blade is a myth.
This is almost entirely wrong. Testing both - static and dynamic - shows that curved forks, even a moderate curve to rake the fork around 45mm, deflect much more than a straight leg fork. And the more the fork legs are raked, the more compliant the fork is. Steel straight leg forks are for ease of manufacture or aesthetics and are a negative for ride quality. There have been numerous tests showing this - Rinard's tests as well as Heine's tests in BQ Vol. 6 #3 . It's also easy to double blind test for yourself. The lever arm for curved forks is in a different spot than straight blade forks and gives much more compliance.

Straight blade forks flex sure but they flex much less and in different places than curved blade forks.

with the same rake and tube diameter/thickness, forks will perform the same- straight or curved
Impossible, a raked fork will not have the same tube diameter or thickness as a straight blade fork due to how the legs are bent. So in addition to the difference due to the curve there is always a tubing issue as well.

What's also fun is that it's possible to back into seeing the different fork flex from different fork rake by mounting low rider racks that attach at the drop out and the mid-fork eyelets. On a curved form the change in compliance is extremely obvious - the fork gets much stiffer as the primary area of compliance is triangulated and allows little flex once a rack is attached. On a straight blade fork there is very little change with low rider racks as the compliance is almost entirely up near the fork crown where the tubes are much larger in diameter and much stiffer due to proximity to the crown.
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