So my friend got a 89 Moto 4 240 awhile back. After doing some work on it, it wouldn’t stay started and the electric start would make this whining sound. When you actually pull start it, it would sound like the electric start is trying to run at the same time. We pulled the starter an put jumper wires on it, it acted like it was locking up an binding up the flywheel and causing it to stall. So we gutted the starter, cleaned it out real good, and just put the shell of it back on to keep dirt out. Used the pull start an it ran just fine. So now we have a brand new starter, installed it, an it’s doing the same thing. I’m kind of at a loss at this point. What would cause a starter to go bad like that, or is it a flywheel issue? Does the starter always turn with the flywheel after starting?

 

The gear behind the flywheel, that the starter turns, is on a one way clutch, once the engine starts this gear should stop and the flywheel and crank revolve round in the middle of it. Your starter was fine, it was this one way clutch behind the flywheel which has seized, and is turning the starter gears and starter. Even possible someone has put the clutch in backwards, so it free wheels when the starter is working and locks, so turning the starter, once the engine is running.