So in this problem there's a lot of leeway as far as parameters go. The numbers I give for weights, dimensions, etc, may not be super realistic, but that's not too important to me because I can plug in realistic numbers later. I more of need help understanding the concept of moments of inertia. 1. The problem statement, all variables and given/known data Determine the maximum acceleration that can be achieved by a motorcycle without causing the front wheel to lift off the ground. Select a real-life motorcycle and research its geometry and inertia properties including the inertia properties of the wheels. Don’t forget the rider! Also, determine how the maximum acceleration depends on the horizontal and vertical positions of the center of mass with respect to the points of contact between the ground and the wheels. Vehicle starts from rest. Assume no slipping. 2. Relevant equations sum of moments around point of contact of rear wheel with ground = 0 moment of inertia wheel = mr^2 moment of inertia motorcycle body (solid cuboid) = (m/12)(w^2+h^2) moment of inertia rider (solid cuboid) = (m/12)(w^2+h^2) M=I*alpha parallel axis theorem = I+md^2 3. The attempt at a solution I'm not super interested in the numbers quite yet, just the concept. Essentially what I have done is I have figured out the moments of inertia for the two wheels, the motorcycle body, and the rider, all about the point of contact of the rear wheel with the ground, which I am calling point O (I've included a rough diagram below). I'm treating the body and the rider as a single rigid body, though I am keeping their center of masses separate. From there I figured that I can't just sum up the moments of the weight forces of the wheels, body, and rider around point O, because the instant that the bike starts accelerating, the moments of inertia of the bodies around point O add an extra torque around point O. Therefore, I need to sum the moments of the weight forces around point O, as well as using the parallel axis theorem around point O on the moments of inertia of each body. That will leave me with an equation that looks like this (all torques around point O): (weight torque of front wheel)+(weight torque of back wheel)+(weight torque of bike)+(weight torque of rider)-[(sum of moment of inertias around point O)(angular acceleration around point O)]=0 I can then solve for the angular acceleration and take it from there. The problem is, I'm not sure if I fully understand the concept here. The other thing I'm not sure about is to me it would seem that the instant the bike starts to accelerate, each mass would have a horizontal forward facing force as well as its downward facing weight force. If this is the case, then I have to account for more moments than I was thinking, but I don't know if that's flawed thinking or not. Thanks guys!