makeinu

To accelerate the bike to a certain speed the wheel size itself doesn't matter because even though smaller wheels have a lower moment of inertia they also have to be spun faster (and, in fact, we've looked at the equations here before and it turns out to be an exact wash).

Therefore, smaller wheels will only offer better acceleration if they are lighter. Now, although it might be argued that the lowest possible physical limit on weight should be lower for smaller wheels, folding bike wheels are almost always built closer to the relative design proportions of BMX wheels (in terms of the relative spoke angles, relative spoke hole placement, relative hub widths, relative flange heights, etc) than road bike wheels and even when the designs are more optmized for speed they still usually suffer due to the economic infeasibility of tooling up with the same state of the art manufacturing technology used to build the (more popular) larger wheel sizes. So in the end it seems that, more often than not, folders have worse acceleration not better.