Originally Posted by
London commuter
I think this comes down to a definition of "lock up" the front wheel. Perhaps it is a USA meaning, but it seems most people here take that as meaning lifting the rear wheel. In that case, yes, I can do that. Easily. In fact, coming down my ramp to the parking at work I do that every day, just for kicks. Then again on the way back up. Well, this seems like a pretty strange definition to me - how can something that is "locked up" still be turning??
The reason that the back wheel comes up is that the front wheel is no longer turning on the axle, the disc is no longer moving through the clamps.
When you stop the wheel from turning (lock it up) one of two things will happen:
1) the bike will pivot on the front wheel, lifting the rear wheel up.
2) the front wheel will start sliding.
If the former happens then this means that the friction between the front tyre and the road is strong enough that it wont slip, and the only way for your momentum go is over the top.
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