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In my physics book, a formula is derived for precession:

[itex]\Omega[/itex]=[itex]\frac{T}{L}[/itex]

I get that tops and gyroscopes and such rotate around the vertical faster as they slow down. I can even see, looking at the acceleration vectors along the rim of a wheel under torque, that a point on the wheel with a small ω would spend more time under acceleration, and thus end up with a greater maximum perpendicular velocity compared to a wheel with greater ω and the same torque. But what bugs me is that, using this formula and that vector approach, as the angular momentum approaches zero, the precession velocity would go to infinity. Everyday experience seems to contradict this. If I hold a bicycle wheel that is just barely spinning, and I apply a torque to it, it doesn't shoot off to the side at near infinite speed!

My book seems to hint at an answer, pointing out that the above equation is only valid if Ω is much smaller than ω. But that doesn't seem to be enough to get me started. Can anyone help me understand this?