Three things that you can do for sure.
1. Send the cylinder to a dirt bike shop and have an extra transfer port added and enlarge the current ones. A good experienced race tech. can do this no problem (I've had it and seen it done many times).
2. Get the flywheel lightened at the same shop (Flywheel being the one in the crankcase - there are two flywheels in the bike).
3. Get the other flywheel lightened (the one with the cooling fins that fits over the stator). Either replace it with a fiberglass one (do they make these for mopeds?) or turn it down smaller diameter wise. Tootaloo!