05 350 stumbling/jetting issue

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bowtie

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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 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.
 
they say don't compress the needle because there is a tiny spring in there, the only way you could compress it when inverted, is to actually push down on it. So just invert it and let it rest on the spring and then measure it.
 
Float height is definitely a good thing to check and set.

How clean is the K&N and Outerwears?

Is there an external fuel filter?

If the fuel in your area uses ethanol at all, you'll need to double check the jets again. When you clean them, take a sewing needle and poke through them to clear any solid matter. If you have an air compressor, blow them out well after that.

What happens is that ethanol absorbs water from the air when it sits for any amount of time, ethanol combined with sufficient water is quite corrosive. That creates a greenish/white residue (mostly oxidized aluminum) that sticks to brass. Carb cleaner alone will not get it off/out.
 
I re-adjust the float and actually got it a bit to high because it would very slowly leak fuel from the over flow vent.

The K&N and outer were very clean when we got it, and i even rewashed the outer and got nothing out of it.

I didn't see any green in the carb and I also used brake cleaner to spray it out.

When we got to Glamis 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 was down on power but I wasn't gonna re-jet out there.
 
bowtie said:
I didn't see any green in the carb and I also used brake cleaner to spray it out.

It may be more white-ish with little green... Brake cleaner will not dissolve it, nor will it provide enough pressure to move it.

Like I said, use a sewing needle, make sure the orafices are clear of debris or residue, then blow them out with an air compressor if possible.
 
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