Originally Posted by curtwally

Hi,

I am guessing that you have a large frame size which seems to be a common (but not exclusive) theme with speed wobble. Geometry of large frames seems to be a cause. I remember a few years back a poster talked about out of spec forks being a cause. I like the suggestion of seeing whether another fork with differing rake can be substituted. I suggest contacting manufacturer to see if this is possible. And yes as many posters have noted holding your knee into the top tube can stop or prevent the vibration. But unlike some posters who suggest this is a minor problem.... it is not. I witnessed a high speed down hill mountain crash which resulted in broken bones. I would not ride this bike at speed downhills until changes are made, up to and including getting a different bike. A bike that does this is just dangerous. curtwally