I have an 03 raptor with slip on fmf pipe, k&n filter with outerwears and rejetted mains, a/f screw 3 1/4 turns out. I was in the middle of a snow cross race and it died. after letting it sit for a while it restarted but after it runs for a bit it dies. just before it completly dies it will idle but when you touch the gas it just dies. choke has no effect on anything. i had the same problem last year and it turned out to be not getting enough air ithink because it turned into summer and it ran awesome when i took the lid off. any helpful suggestions would be appreciated. I dont think its elecrical because everything tests ok by the manual. i am hoping someone has had the same problem and can help.

 

Could be a plugged vent line, on either the gas tank or the carb.

 

Get 'er in a warm place for a while and drain some fuel out of the tank..........you're looking for Water.

When water hits a carb that's as cold as yours is,.......it freezes, then the carb warms up long enough to flow a bit, then you run it, then it freezes again,.......... then it warms a bit sittin' there,......You gettin this???

This is truly just a shot in the dark, but I've seen it in cold weather on air cooled engines......(especially two strokes)

Might have to put a carb blanket on it or some sort of home-made heater....

Good luck.

 

JUST A GUESS BUT IT SOUNDS LIKE PROBLEM MY BROTHER HAD WITH HIS QUAD! CHECK THE CLAMP AROUND THE CARB AND SEE IF THE CLAMP IS TIGHT AND IF THERE IS A MEDAL LIKE BUSHING ON THE CLAMP MY BROTHERS CAME A LITTLE LOOSE AND AIR WAS GETTING INTO THE CARB ACTING LIKE A CHOKE WHICH STUDDERS AND EVENTLY WILL STALL. IT REALLY ACTED UP WHEN HE JUMPED. GOOD LIKE WITH IT!

 

i am hoping to test these theories tomorrow, air filter is fine, have some isopropyl for water in gas and some new gas, gonna pull carbs off and give them a good cleaning, and while i have it that far apart i am gonna check the boots. thanks for the input and any other ideas are more than welcome. I can swallow my pride and admit i dont have a clue what the heck is going on.