Rear hubs on US sold motos are usually British threaded, so if you need a new rear hub/wheel on the Schwinn, the one off the moto will work as a replacement. The spacing may be different, but probably not different enough to matter. It can also be fixed by adding a couple of spacers to the non-drive side and re-dishing the wheel. But as is generally agreed, don't use the moto fork on the schwinn because the threading is definitely different.