I have a 2006 Yamaha Kodiak 400 4wd and my issue is after riding for 3 to 4 hours just easy riding trails the machine will start backfiring and shut down. I let it sit for 5 minutes will start right back up and run for about 10 minutes and backfire and shut down again. After letting it sit for 5 more minutes will start back up and run for 1 to 2 more minutes then backfire cough and sneeze and shut down but then it won't start until it sits till the next day. When all this happens I have checked and have spark, tried removing gas cap, fuel runs from the drain plug on the bowl. I have thrown money at it by replacing or rebuilding the carb, CDI box, ignition coil, stator & regulator rectifier...This is my wifes quad and she won't ride it any more because it always needs towed back. This same chain of events plays out exactly each time for the past 10 years or so. There is no problem riding it for an hour or so just the 3 to 4 hour time frame. Me and the guys I ride with are all baffled, I am missing something and hope you all can help. Thanks in advance for your replys....

 

Sounds like it might be overheating....if aircooled check fins for mud buildup, or mud in radiator if liquid cooled. Check plug color when it quits, dark black is rich or light grey to white is lean...I had a Praire years back that would overheat the fuel line where it passed over the exhaust and cause it to lean out after a good ride, some self stick heat tape cured that problem. Also crud in fuel tank may reduce fuel flow to cause the stall

 

Plug color is perfect radiator is clean and coolant level is full. Fuel line I will address for heating. Good thought thanks.

 

If you had these problems for 10 years you should have dumped this dog 9 years ago - lol