2005 summit 800 help me please.

[byrd2829]

I have a 2005 summit 800 which only runs on one cylinder until it reaches about 4500 rpm, then the second one kicks in and it runs great. It then goes back to one when reaching lower rpms again. Any suggestions. thanks

 

[attatoy]

Compression check the engine. You can switch your spark plug leads from side to side(simease coil fires both holes) to see if the missfire changes cylinder .Spray water on the exhaust to see which side is running ( the exhaust will be cold on dead side).....then chase the issue. do you have a comp gauge? do you know what side is dead at low rpm?

 

[eddy]

One cyl dead

Sounds like pilot jet plugged. Replace both sides, 17.5. $4 each!