Well, a 2 inch pulley on the motor means you'd need a 23.2 inch wheel pulley. Might as well put a wheel on the motor and have the wheel rub against the tire since it's 26 inches.

 

Well, a 2 inch pulley on the motor means you'd need a 23.2 inch wheel pulley. Might as well put a wheel on the motor and have the wheel rub against the tire since it's 26 inches.

That is the reason you see many things that use a Vbelt and needing a large reduction use a "jack shaft", when a gear box isn't necessary. Even stuff with a gear box, like a lawn tractor use a jack shaft or compound pulley to keep pulley sizes down and distance between motor and final drive more compact.

Another problem with using a very small and large V pulley is belt "wrap". The amount of wrap around the smaller pulley in degrees of angle. When you don't get enough wrap on a pulley you end up with more slip.