My son hasa 70cc yamoto it has ran really well. The other day he sut it off and now it will not start. I am getting spark and gas. I even changed spark plugs and took the carburetor off and cleaned it. Still nothing does not even hit a lick. I don't understand it has ran fine for a couple years up to now. Help!

 

Any luck on this? I'm battling this same issue. Finally got it to start up tonight, then it fired up right away once warm. Soon as it cools off I have a hell of a time getting it to start again.

Thanks!

 

Have you tried adjusting the valves? This needs to be done periodically, and hard starting or no starting when cold is the classic symptom.

 

That was actually my next thing to do lol. Is it a pain to do, or fairly easy?

Soon as it's warm I can barely hit the start button and it fires right up!

Thanks for the reply!