05 Raptor 350 stumbling/jetting issue

[Bowtie]

Ok, so my g/f bought an 05 Raptor 350 SE Friday night that is all original with the exception of a K&N air filter with the outerwear and the end cap/sparky removed. The carb had the original jets in it, 142.5 main, 22.5 pilot, a/f mix is 3.5 turns out, the needle has three clips and is on the third and we are around 1200 feet on the altitude. The bike fires right up, you barely need the choke, it idles fine and there is no back firing on acceleration or deceleration. The problem is when you are at WOT and you get into the upper rpms it sputters pretty good.

I did some 4th and 5th gear blasts and killed it and pulled the plug to find a white plug, so I figured lean. So I went and got a 145 and a 150 main jet and tried each one and no change.

So I start thinking there is a vacuum leak and so with it idling I sprayed it and the boots down with carb cleaner and it changed nothing.

So I started thinking it is running out of fuel, and so I cleaned the bowl, jets, needle, seats, everything I could. Drained the tank and put in fresh 92 octane because I had no clue how old it was. No change and at this point I am stumped! I am going to try and get a new needle for it since it is the original, gonna call the dealer/shops in the morning.

As for adjusting the float, how do you guys do it? The manual says to invert, but don't let it compress the needle, but it does it as soon as you flip it, so I set it with it compressed and figured if anything it would just have a little extra fuel in the bowl and it's not leaking out anywhere.

Do these have a rev limiter in them? If so, what is the rpm on it? Any help would be greatly appreciated because we are leaving for Glamis Friday morning and would really hate for her to have a bad time because this thing wont run right.

[bucknaz]

That's odd.
I ran a 2005 Raptor 350 SE last year with a LRD slipon, K&N filter and had it rejetted. I never had any problems with the engine.
I did however find that the frame isn't built for jumping so I had it welded back together every other week.

How did the top end run w/ the original jets before you started changing them out?

[Bowtie]

It was doing it as soon as we bought it. Long story, but I thought the g/f had gotten it up to speed because she was gone for awhile on the test ride and came back and said it ran fine. I discovered it after we got it home, which is my mistake, I should have rode it.

[bucknaz]

you should of bought my 350 from me, it ran strong...

Wouldn't the white plug indicate it's running too hot and or too lean?

It could also mean that you have a crack in the engine (worst case scenario).

My guess is that you have the wrong jets in the carb.

[Bowtie]

You sold it before the cash came in! The plug shows lean here in Phoenix, but it ran hard at Glamis, I didn't pull the plug out there, so no idea what it looked like. When we got there it had a horrible flat spot about 1/4 throttle to almost WOT, so it was a short ride to Olds hill and back. I moved the clip from 3rd position to 2nd and that 350 was screaming! The G/F buried it 4 times!!!! It would pull Olds in 3rd with no problem, but just didn't have the power in 4th, it felt down on power but I wasn't gonna re-jet out there. The high rpm stumble was gone completely and I had a 150 main jet in it. I had more problems with my 450 then I did with the 350!

[ElderGeek]

Lots of quads and rails were "down on power" at the dunes this weekend. Much of it to do with the wet sand, and most duners being over paddled. Read too many or too stiff or too tall. With the wetter sand this last weekend as opposed to lighter fluffier sand after periods of no rain, the paddles are pushing heavier sand making the motors work harder, keeping RPMs down.

I would go to the desert somewhere and spend a Saturday working with different jets. Or take it to Rudy and let him do it.

What does the pipe look like? Dark black, grey, light grey, no color at all?

[Bowtie]

The pipe looks dark grey to black. I will take it out in two weeks and go rail on it and see what happens, next weekend i have to help my cousin move so my weekend is shot.

[desertdeweller]

I think I would try 2nd from the bottom on the needle and a little bigger on the main than the 150 maybe even 160 especially if the lid on the air box is off too.

[Bowtie]

The needle only has 3 spots, and is on the middle. The lid is still on it. Whats weird is it ran perfect in Glamis but here it stumbles. I wonder if it has anything to do with there it is in sand and so the load on the motor isn't as hard, because here I am on pavement and the tires hook good and hard.

[desertdeweller]

If your on the ragged edge of it the weather could have made a difference down there too. if it was a high humidity weekend etc. Since it only has 3 positions on the needle I would go to the bottom one and still go biger on the main. Your better off working from rich down less likely to hurt the motor that way due to detonation etc. did you check the plug while you were at the dunes?