My 2001 raptor has the exact same setup as yours and the exact same problems. I have had the carbs off many times trying to cure it but no luck. When yours is in nuetral and you give it 1/4 throttle does it seems as though it is missing? Hopefully someone can help us out.

 

pull the plug out and check our plug. dark means rich, white means lean then go from there.

 

In conjunction with GregV's problem...a loose battery cable will cause the same problem.

Regarding the muffler...try running it with the spark arrestor removed.

Have you tried 142/144 mains?

With my stock motor and Dynojets it ran best with no lid, K&N, slip on exhaust, 146/148 dynojets, with the needles in the 3rd slot and the fuel screws somewhere between 2.5 to 3 turns out.

 

I have done the plug check a and everything is fine at wide open throttle. Just went and checked the boot that wasn't the problem. Pretty sure the battery cables are tight. It misses the worst when going up a slope at around 1/4 throttle and has a miss through the entire rpm range when revving in nuetral. Thanks for any info.

 

have you tried putting the stock jets in and taping up the holes you made? i'd start from scratch if i were you.

 

It has been sputtering for almost a year now. The only things I had done when it started was the Dyno-Jet kit and removed the spark arrestor. I am beginning to believe that its an electrical problem since nothing i change in the carbs affects it.

 

Since both you (wheeliedude) and raptor630 are having the same problems with the same stock pipe modification, you guy's may want to think seriously about choosing an aftermarket pipe. At least go with a slip-on that has be engineered for the Raptor. There are occasions when we can make a few holes here or trim a little off of something over there and actually find a combination that works. But I would have to say that doesn't happen very often. It sounds to me like drilling these 3 holes may not be the way to go. If you wanted to go back to a stock pipe I'm sure there are plenty of us who have them that would give you a good deal on one(mine included - it's practically brand new).

After fighting for upwords of a year, chances are you probably are not going to be able to cure your problem with jetting.
I think it's time to go pipe shopping. JMO

GregV

 

Mine was already sputtering at 1/4 throttle before I modified the pipe and airbox. So that couldn't be it. I'm gonna get a new plug cap and try it. If that doesn't cure it then I guess I'll take it in and have the ignition system checked. I know the timing is spot on and the valve clearance also because I checked these myself. It runs great 90% of the time but the missing/sputtering is agravating.

 

Wheeliedude,
Same thing happened to me when I got the DJ kit. I don't have an exhaust or any airlid mods. I also noticed when applying the choke it got worse so I figured it was rich. It ended up the only way to get it to run right was to go lean , leaner than what dj recommended and it ran great.
this is probably your problem.

 

Lets get a pool ($$$) going

I'll bet $20 that 142/144 mains will work.