Has anyone run into this? I've got an 03 Raptor, it idles fine but as soon as I hit the throttle it just farts and backfires, it sounds like it's electrical, any suggestions.

Thanks

 

did you check the parking brake sensor on the clutch perch? With yamaha the parking brake sensor is the cause of the problem you described most of the time. Try wiggling the sensor around, and if that doesn't fix it try unplugging it from the harness. I think there's 2 sensors on the raptor's stock clutch perch, and the parking brake sensor would be the one closest to the front of the quad.

 

check your reverse plug in dowm by your shifter. i had this problem. yhe reverse sensor got unplugged from the motor. just above your shifter on the motor . see if its plugged in.

 

Did you ever figure out the problem? Mine is doing the same thing

Thank you
Kory

 

my brother (caliraptor) had that same problem, it turned out to be the reverse rev limiter under the shifter. he just disconnected all the sensors in the handlebars and grounded the reverse limiter. try that, it should work

 

Spitdirt has a similar message string. If it's an actual stall and not running rough, it could be a very common raptor carb problem. (Quote from other string) Your 660 is equipped with twin Mikuni BSR CV carbs. They work ok, but it doesn't take much to screw up their circuit. On your carburetors, the throttle cable actuates a butterfly valve and, as the throttle is opened, the air pressure difference between the sealed chamber above the vacuum slide and inside the carburetor venturi forces the slide (located in front of the butterfly valve) up and down. This will NOT be a factor at idle, only when you press the thumb throttle. See if either of the hoses connected from the top of the carbs to the intake manifold have disconnected or are blocked. They are not clamped, so one or both may have issues. Good luck.

 

sounds like a ground issue, happened to me when the parking brake sensor on mine came loose and touched my bars

 

Thanks for all the help... It was the parking brake sensor... unplugged it from the wiring harness and she runs like a champ!!!

 

We have a legend amongst us folks, ATV land speed record holder Terry Wilmeth

 

Legend? um, not really......I would more likely call myself the Oregon Nutcase that is suffering from a massive mid-life crisis. But, thanks anyway![img]i/expressions/face-icon-small-wink.gif[/img]