Hey guys, before i start let me say this is NOT a bashing thread. My brother is having major trouble with his raptor and if we dont get this thing fixed it's gonna nose over and kill him. And yes before you say it i have gone back and read past threads for information first. So here goes

Hes is having a major trouble with throttle response. When he blips the throttle he has alot of popping, and when he is under power on a jump and tries to pop the throttle on the face of the jump it noses over on him

Ok his stuff:
02 raptor
K&n stage 2 kit jet set (Needles / jets and filter)
145L/150R stock air screw setting (never been changed)
Lid in place w 5 little plug filter vents in the lid.
Until now he had the left clip on three and the right clip on 4 spots down (just had him move it back to 3)
Fmf power bomb headpipe
White brothers exhaust w 6 disks (has 4 more plus a turn down tip if needed)
And at 990 ft above sea level.

Black sooty plug .

Any ideas where to start??????
He needs help cause if he does not get it fixed soon...he just might go .......POLARIS!!!

 

Did he just do the jet kit etc? Or has it been running fine until just recently? If he just did the kit and is now having these problems. You might recheck everything. Includeing and possibly most important the float adjustment. There is a thread here somewhere by SixSixT that explains a good way to adjust the floats. The K&N and Dyno Jet kits are the same if memory serves and the jets are not numbered 145 150 etc. I believe their reccomendation for what you list would be 146 148. If your useing stock mikuni jets I think I'd go 150 155 with a pipe and lid on even with some holes. Turn the fuel air screwsd out 2 1/2-3 turns on each carb, they are located on the bottom at the head side of the carbs. Seat them lightly then turn them out to your desired amount. I'd put the needles (stock) on the middle groove and needles that came with the kit (if used) on the 4th groove. Make sure the needles are in their holders properly and seated. Make sure there are no tears in the rubber diaphrams etc. Theres probably other things to check. It could be as simple as a loose parking brake connection at the brake lever. Even as difficult as some type of electrical problem. Good luck. I'd leave all the plastics off until the problem is resolved, I'm sure you've discovered that by now though. I'd use all the disks to for the exhuast.

 

Thx, ill tell him. I think he was just running way rich last year. And probably not at its best. When i pulled his plug it looked like coal. He has it tore down right now. BTW This has to be some sort of karma... a redskin/yamaha fan helping a Polaris/Cowboy fan.

 

Now that i think of it he does have the parking brake blocked off ill have to see how he did it and what he did with the electrical side of the issue.