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Rough Running Solved

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I put my Euro style muffler back on and now my bike runs smoothly at any RPM I choose to run at. Therefore, using a stock, uncorked US pipe, which created a much more free-flowing exhaust situation, created a mis-jetted situation on my bike. So mis-jetted that the needle position by itself wasn't enough to fix the rough running. It still backfires though, so I will try the adjustments that have been recommended, (unscrew the pilot adjuster or get a richer pilot jet) but not till this coming weekend (ugh). Also, the more restrictive pipe does not allow me to bring the front wheel up as easily.


So, if I want more performace using the Euro muffler, I could try the jetting you have been discussing. I would probably need to modify your settings somewhat for altitude. Any thoughts?

Anyway, I'm glad to be able to report a cause and effect so I can provide a little back to this great group.

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great to hear that you have got a bike that you can ride. i'm sure i speak for many riders when i say that it's dreadful groping around in the dark unable to desifer rich from lean.

JD knows more than me about many of these altitude applications.

i have learnt a lot this weekend about the relationship of the pilot air jet and the pilot jet on each other and everything else. i swore i was headed in the right direction in the spring and so i'm now a little concerned that i shouldn't jump up yet again.

the bike was excellent yesterday in a motocross enviroment. i rode my wr400 and a ktm 400exm that was converted to semi motox spec and think that i preferred mine. the katoom was better in the midrange and was so light at the back that it would break away coming into corners.

i think that i will come up with something in the next 14 days. i can't gaurantee that it will work. at the end of the day the parts are cheap, it can be rewarding learning but it's tough to sort things at the other end of a keyboard isn't it!

jd and i agree that the straight part of the needle _ _P or N or M are all close but by using an 'M' i've been able to back the pilot system right off. an 'N' is the halfway one.

i've found out why i couldn't finish the job in the spring and now we move forward again.


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