I am sure this is a simple problem, but I am posting this thread to make sure I understand it properly: If a motorcycle requires 3000N of force in order for it to achieve a certain speed over specific terrain and allowing for wind drag, etc. (I.E to counter the sum of the resistive forces acting against it), then it will need 3000N of thrust. This could be accomplished by an immensely strong person pushing the motorcycle or by a shaft and bevel drive connected to one of the wheels creating 3000N of ‘push’ where the tyre contacts the ground (directly below the axel). However, if the wheel has a radius that is three times that of the bevel cog (the cog attached to the wheel and driven by the drive shaft) then in order for the wheel to have 3000N of push against the ground (road surface) the shaft drive would need to input three times this 3000N into the cog. E.g. if the cog, that is directly mounted to the center of the wheel, has a radius of 0.1m and the wheel, that is three times larger, has a radius of 0.3m then the drive shaft should exert a force of 9000N upon the cog in order to achieve the required 3000N of thrust at the ground/tyre contact point. Is this correct?