Starter spins but doesn't start the engine
 

Hey so I have a chinese quad 125cc I have had quite a few problems but most of them were easily fixable but now I have another problem after I cleaned my corb i was driving the first day after the fix and i got surprised my engine just shut off and i couldnt start it in any way it would spin and not start or start and shut off after I go into forwards gear. My atv has an automatic gear box. I have no idea what to do so im looking for help here.

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