Motorcycle Wall of Death Some pointers would be greatly appreciated please. A motorcycle is slowing down, but maintaining its height on a 'wall of death' (a vertical cylinder where the motorcycle 'drives' around the inner circumference as a stunt). A spectator takes timings in milliseconds as the motorcycle passes a set point. Armed with only these timings, the wall dimensions and the time at which the motorcycle dropped, how might I determine the actual speed at which the motorcycle finally falls off the wall, and the position around the wall relative to the timing point (or total distance covered since any one of the timings) when this happens. I'm not sure that the basic equations of constant acceleration will work out here as I assume friction will be a factor which decreases as the cycle speed decreases. It's been 20 years since I sat in a maths / physics lesson and any help would make me look like the intelligent father I often pretend to be! Thanks to all.