Had air leak around intake manifold it is prone to leaking there,also need a new cylinder,piston was fried from.previous owner running with no oil,I suggest getting a motoforce 50cc cylinder kit if your staying stock or if your going to 70cc go with a well known brand like,malossi,stage 6,polini these cheap Chinese kits are junk,come over to 49ccscooter.com and join best scooter form on the net no b.s either,my name is jwhood there also and you can see my build in the build thread and also get help for your issue hope to see ya over there