runs fine when cold. won't run when hot
 

My cayman 50cc runs great when its cold but cuts off when it gets up to temp. The engine was just redone by motowest and also has a new carb. I hope its somethign simple but looking for all the ideas i can get. Thanks.

runs fine when cold. won't run when hot
 

Any ideas would be appreciated. Really

runs fine when cold. won't run when hot
 

im no expert but check out the choke.

runs fine when cold. won't run when hot
 

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As a suggestion, do the following:
- Check the engine compression when cold and when hot (when its not working). Compare these PSI numbers to pure stock PSI and the PSI numbers your engine builder feels the engine should be running at.
- Check the chock. Personally, I hate "auto chokes". One can never trust when they work or don't work. If you can, install a manual choke. Thus, "you" control its choke function at any temp range.
- When cold, check its stator output readings. When its hot and dies (or is dead), check its stator output readings.
- When its dead, do you still get a spark across its plug? If so, sounds like a gas flow problem. If not, sounds like a stator / CDI / External Ignition Coil problem.

When it dies when hot, please provide more symtoms / behavior leading up to "when and how it dies". For example, does it start to lose high RPM and its slowly creeps down to the lower throttle range? Does it suddenly die (in all throttle ranges)? Does it run while hot and if turned off, it won't go again?

Hope these ideas help as well....

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runs fine when cold. won't run when hot
 

The motor just suddenly turns off when its up to temperature. It has a manual choke. I can restart it but it will not stay running. Almost sounds like its bogging out when u give it gas. If i pu t the choke on full when its hot it will stay running at a rough idle but it will not have any power. I wil have to go check the compressions again. I had heard about a bad stator. Would that cut off only when the engine is warm.
THanks for the advice.

runs fine when cold. won't run when hot
 

The "put the choke on and it'll run" statement points me toward the carb.
Normally I'd think it'd be electrical.

runs fine when cold. won't run when hot
 

Is the air vent to the fuel tank working properly?

Just a thought...

runs fine when cold. won't run when hot
 

i put the original carb back on and it seems to run fine in the garage (jack stand). I will try to get the kids to drive it in the back yard and see how long it stays running. Didin think to check the vent tube so I'll clean that too.