Basic Flywheel and Ignition Modifications   or  Advanced Race type ignition

	This photo shows the flywheel hub attached to the left side of the crankshaft. The hub, which has been cut out of the flywheel assembly contains the ignition advance mechanism and the eccentric which opens and closes the contact points. The hub is a steel center piece riveted into the aluminum outer ring of the flywheel. The outer ring contains the permanent magnets which provide power to the ignition system. I will be using a small 12v battery to power the ignition for several reasons. The battery will provide a more consistent and reliable 12v and the removal of the flywheel outer ring will trim 3 lb off the weight of the crankshaft assembly, This is a huge amount considering the entire crank assemble only weighs about five pounds. The Clutch unit mounted to the right side of the crankshaft weighs about 2 lb which should provide a sufficient flywheel effect. The motor should rev much quicker without the 3 lb flywheel but quick starts will be a little more difficult, I don't feel this is much of a factor considering this 50cc class requires the rider to push start the bike on the starting grid.
	Here is a photo of the flywheel outer ring after removal. I just cut it off with a good jig saw using some existing casting seams as a guide. The aluminum is quite soft and cuts easily. Care must be taken to cut accurately in order to keep the hub as well balanced as possible. I'll do some final shaving of the hub with a hand file. The small diameter and lightweight of the remaining aluminum attached to the center hub should not present too much of a balance problem. From what I have learned the stock Clutch unit is where the majority of balance problems arise, sometimes even breaking the crankshaft at very high rpms. Hopefully I will be replacing the contact point ignition with an electronic unit after the bike is raced a few times.