CFMOTO Dies when warm
 

Having a weird problem on my 250cc CFMOTO.

When I cold start it, it runs great. no problems at all. Seems like it idles a bit fast, but no big deal...

I drive it around for 10 minutes or so - plenty of time to warm up, and it gets to where it bogs and dies. I can typically start it up and it'll idle low, but if I give it any gas at all it dies.

I let it sit for 5 minutes or so, then it starts back up with high idle, runs okay for about 15 seconds, then dies again.

Seems like there is something thats making it mad when its warm. Any ideas of something to try? I've tried draining the gas and putting new gas in it. I've also tried taking off the carb, cleaning everything, putting silicone gasket sealer on the intake and tightening everything back up - still same thing. Runs good for about 5-10 minutes then bogs/dies.

One other thing - I run no ethanol premium gas in it - so I doubt its the gas. Cold, it starts up very easy, while my other buggies have that e10 stuff, and after sitting for about a month, I have to drain the carbs in order for them to start.

any ideas?

If its not overheating then it sounds like its fuel starvation. Check your flow from the gas tank....maybe its vapor lock.

Does your carb have the elctronic fuel enrichment valve?If yes-and it's not working it will cause your issue.

BTW: Your SUNL is really a CN250 engine. I doubt you have a high and low range transmission in this buggy.

It's a CN250 then... it's got the CVT, not High/Low. I guess I had them confused.

Both are good points, and things I have not tried yet. I'll try both and reply with my findings.

Both engines are made by cf moto though. It does sound like you have a bad choke/enrichener.

I had the exact same problem when I first got my GK-06. Ended up replacing the fuel line. The fuel line they used was so long that it hung down too much. My buggy gets fuel fed by gravity...no fuel pump so the straighter the fuel line the better the fuel gets delivered to the carb. Make certain you have NO fuel leaks, that the petcock (if so equipped) is turned on and try it again.

this was a year and a half ago - seems like not that distant.

anyway, it turned out it was the fuel enrichment circuit - if I remember right, I unplugged it and went riding and didn't have the problem (had other problems since it was unplugged, but it didn't die)

I bought a new carb and swapped the enrichment circuit between the two and been doing fine ever since.

in fact, I started my buggy about a month ago and it had been sitting unused for at least 6 months - nothing but the battery maintainer hooked up to it. was amazed to see it fire up so easily. I attribute that to the ethanol-free premium gas I put in it. I think it might have had some stabilizer in it also.

Funny you should mention fuel lines though because I forgot I need to replace them on mine. Last time I was out, I think the lines I put on it weren't made to handle the small amount of heat from the engine because they expanded and there was a slow gas leak coming from the line. Need to replace that before my next buggy outing which is in 4 weeks!

Glad you got it fixed. Didn't realize the thread was so old.

I didn't realize I forgot to return with my answer.