Need Help w/ The Physics of A Wheelie

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The discussion focuses on understanding how a bike performs a wheelie while accelerating, specifically through the application of torque and moment equations. The key point is that the torque from static friction at the rear wheel must exceed the torque from the bike's weight to initiate a counter-clockwise rotation about the rear axle. The concept of "kinetic moment" is introduced, indicating that mass multiplied by acceleration can create a negative moment that opposes this rotation. Clarification is sought on how these moments interact to allow the bike to rotate about the rear axle. The conversation emphasizes the balance of forces and moments necessary for a successful wheelie.
NJD21
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So the attachment has my FBD of a bike.

What I'm trying to understand is how exactly a bike does a wheelie while accelerating (in the x-direction) by applying equations involving torque/moment.

For equations involving torque/moment:

So if I take the sum of the moments at the axle, I assumed the torque from the static friction should overcome the torque from the weight so that the bike rotates about that point in the counter-clockwise direction; however when applying principles involving "kinetic moment", (mass x acceleration) provides a negative moment about that point (clockwise rotation). And because of this negative moment, I'm not sure how the bike would be rotating about the rear axle.

Any help is appreciated. Thanks.
 

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NJD21 said:
when applying principles involving "kinetic moment", (mass x acceleration) provides a negative moment about that point (clockwise rotation).
Can you explain that part more?
In your diagram, you correctly have the friction forwards on the back wheel at contact with the road, so this provides an anticlockwise moment. If that exceeds the clockwise moment from the weight, the front wheel will lift. What else is there to consider?
 
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