Ok heres the deal, I have read all the posts from the last thirty days about Raptor jetting and whatnot. Noone has had the same problem that I seem to be having. So here goes

I have a 2004 rappy, K&N filter with the K&N Powerlid, both have outerwears on them. I have also installed the GYT-R Carbon Fiber Slip-on. I also have the GYT-R jet kit installed as well. Heres the problem, the bike runs great off of the bottom and pulls hard all the way to the top, but when you run it wide open for an extended period of time, such as down the river bottom, or in the dunes, it starts to cut out and sputter and bog down after about a minute of wide open throttle operation. I have pulled the plug both after slow speed riding, as well as short periods of wide open throttle, and the plug is always black. The other day, i ran it as hard as i could until it began to sputter and pop and bog down, I killed it and let it roll to a stop, i checked the plug and the outer edge of the plug was still black, but the electorde and cermic center piece were white.

It looks to me like the thing is jetted a bit rich judging by the plug when you ride normally, but after extended periods of wide open throttle runs the plug looks lean. I have tried adjusting the fuel level, but didnt notice much difference other than too high of a level just kills it.

Any help would be greatly appreciated, I am going nuts trying to figure out what to adjust and what to change.

By the way, I am running a 25 pilot jet, 160 and 165 mains, and the gyt-r needle clip is in the third (middle) slot.

Thanks again in advance
Tyson

 

To me it sounds like your hitting your rev limiter. It will do that when you hit the peak open throttle. Or your button is sticking on the reverse limiter.....??

 

I was having this same problem when i first got my raptor. It sounds like it's hitting a rev limiter, but it was because there was too much over the airbox. When I first got mine, they left the instruction manual with a plastic bag around it on top of the airfilter, which had outerwear on it. It might be because your filter has the outerwear plus your using the power lid. Just a suggestion.

 

Try running it with the lid off.

 

I cant run it with the lid off since i bought the slip in K&N filter, I need the powerlid to hold the filter in. I dont think the reverse button is stuck since it will run great all the way up to full throttle as well as running great at full throttle for a little bit before beginning to pop and sputter and loose power, I then have to slow down or stop and wait a few seconds before it will run right again, Kinda acts like it is running out of fuel.

 

To me it still sounds like it's getting too much fuel. Mine does the same thing. I have to slow down or stop until it idles normal again, when I go up an incline. It still sounds like you have too many prefilters and filters on it, not allowing enough air into it. I'm not positive though.

 

ok i have had the same problem i bought my 01 rappy it sputterd alot and i put it up and didnt ride it i thought it was a lost cause. it sat for a year and then i fitteled with it and i messed around the clutch i thought it had to do with the electrical componets and i fixed it. it was the top wire going to the clutch if thats not connected tight it will run like its in reverse. try cleaning that and messing with the floats in the carb. i dont know worth a shot

 

I am going to try and take off one of the prefilters and readjust the fuel level back down a bit, I dont think it is the reverse limiter or anything to do with wiring since it only happens when i ride at wide open throttle for an extended period of time.

Does anyone else have a place that they can go wide open for an extended period, such as river bottom or dunes. If i ride hard all the way through the gears and only ride WFO in top gear for a few seconds it doesnt happen, only occurs when i have been at WFO for over 45 seconds or so in top gear. ANy way that perhaps the carbs my be using more fuel than the petcock can supply?????

 

You probably have it jetted correctly for bottom end, but your needle may be in the wrong spot. So when you do get it wide open, and the rpms really start kicking up, it gets flooded. Rarely do you hear someones quad sputtering when it runs a little lean, ussually it will backfire or something like that. When there is too much fuel, it cant burn the fuel and you lose power. Try playing with the needle in diferent spots. jetting is not an exact science, its all about trial and error. You need to test other jets with diferent needle positions and see what does better.

 

IMO if the bike runs well all the way to the top end you are jetted properly to slightly rich on the on the low (air Screws and, pilot) and, in the mid (needle) but you may be lean on the top. Try going up one size on the mains and, do the same test = run it wide open in the River bottom.

The Black on the out side of the plug tells me you are slightly rich in the low or mid but the white on the tip says your lean on the top end!