Originally Posted by jeff800
Bottom Bracket / Drivetrain
I believe that this is the most talked about and least understood of the three flexes. You often hear people say that the stiffer the better and that any bottom bracket flex results in a loss of energy. I firmly believe that to be untrue. Let's look at what causes bottom bracket flex and what it leads to.
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being a bit of a steel fan (even though I do about half my miles on one of my alu bikes), I tend to believe this theory, but a frame that's too stiff isn't the only reason for rear wheel "skipping".
Tyre choice is a factor: if I use a 20mm rear tyre at 160psi, I have no trouble getting to skip.
But the main thing factor is poor technique: moving bodyweight too far forward when off the saddle allows the back wheel to fly all over the place.