Mini-b and I gave up trying to make the generator work on the sprint and decided a modern permanent magnet alternator system would be better . We started by buying a stator system from a Chinese scooter because they are cheap and plentiful. After that we drilled out the center of the fly wheel and welded in the center of the original tapered part of the commentator . Then we designed an milled out a adaptor for the stator. Just have the figure out the wiring now.