> > I didn't notice the straight fork. That's too bad, those look so "cheap".
>> Somewhere (BQ?) I read that the straight blades are actually better for
> > shock absorption. If so, why weren't they used decades ago?
Bicycle Quarterly's tests showed that fork blades do flex. (For those not following technical discussions, there were lots of "experts" who asserted that only the fork crown/steerer tube interface flexed.)
We showed that forks with more rake flex more - longer lever arm. We did not have enough otherwise identical forks to show that a tight bend at the bottom of the blade absorbs shock better than a large radius (or, at worst, a straight blade), but that is obvious from just looking at the way the forces act on the dropout.
A straight fork has to act mostly in compression to absorb shocks -
hence straight blades are used for suspension forks. A fork with a
tight radius at the bottom puts the lower part of the blade much
closer to horizontal, so the blade can absorb shocks by bending,
which gives more travel than compression of the blades.
>I believe the Ferarri F1 program showed Colnago that straight blades
>worked better.
>Could be wrong.
Formula 1 cars have suspension...
Colnago's claim that straight forks absorb more shocks don't seem to hold up on the road. Many a Colnago rider has complained about hand pain during long rides.
Jan Heine
Editor
Bicycle Quarterly
140 Lakeside Ave #C
Seattle WA 98122
http://www.bikequarterly.com