Think with me why motorcycle Vespa comes to an end

I was seeing the picture of a Vespa and there the size of the wheel is very small, and is that the reason, see a normal moto that has a big wheel you the motor is less forced for a very high velocity, see a machine that runs in slow velocity is very dangerous to drive at night. For instance a big wheel the motor will give 20 turns to make 1 km, the motor of the machine that have a small wheel wil give 45 turns to make the same distance, of course if you think in distance you aren't pushing to much the motor till break, is that one machine will work more to do the same work, but when you think in velocity the motorcycle will give 20 turns in a second and get 100km/h but the Vespa lets suppose that have the same motor will give 200 turns to try to compete with the motorcycle, so no matter how better is the motor of the Vespa you use always make a work that isn't the optimize so will give many turns to have a big velocity, of other point view, first the same number of turns is a small distance, the same turns of the motor in the same diference of time is a smaller distance, and that if the two diferents motorcycle be in the same velocity, the motor of the regular motorcycle will be less forced to get 100km/h and the Vespa will got the motor being pushed to the limit. Rute Bezerra de Menezes Gondim