the starter is turning as well as the chain but not the crank, did a weld break on the sprocket behind the flywheel/clutch?? it starts fine with the hand crank. thanks

 

I don't know anything about what engine is used in lion cub ATVs, but I'm betting you have a starter clutch like many other quad engines, and it is slipping. The starter clutch is a one way sprag clutch that allows the starter motor to turn the engine, but when the engine starts up the clutch overruns and disengages the engine from the starter. This keeps the engine from spinning up the starter motor.

 

Thanks, I will be taking it apart today to check it out!