Originally Posted by
vision646
I don't know what you guys are talking about but I also have some high speed twitching. During my ride I reached 40mph coming down a mountain and there were some times when I felt the front wheel twitching, got kinda scary but it was still fun

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What I'm trying to say is that I'm attaching myself to this thread in order to to learn something.
What you're likely talking about is the high speed wobbles, which is a different issue from how the bike wants to turn.
Short answer to your problem is put a knee to the top tube when it happens. Long answer is read some of the threads on high speed wobs.