Strange idle problem

[bukwheat]

Here is the link to the video with the idle problem at the beginning.

http://www.youtube.com/watch?v=mwW7-2FyzPU

[hannesd]

did you get your squish set correctly?
exessive squich (as on most standart bikes) can lead to irregular idle.
makes them very sensitive to changes in temp/altitude.
next thing that comes to mind is also a blown crank seal.
just a thought.
does it sound like it's running somewhat rich off idle? (edit : after watching the vid longer, definately running rich off idle if you ask me, doesn't run crisp)

hope you get it fixed soon.

ciao, Hannes.

[bukwheat]

The squish should be good, never have had the head off. Its totally stock. I think what you're hearing is me lugging it in higher gears. I usually run 3rd or 4th gear in pretty tight woods. It could probably run a bit cleaner.

[hannesd]

Originally Posted by bukwheat

The squish should be good, never have had the head off. Its totally stock. I think what you're hearing is me lugging it in higher gears. I usually run 3rd or 4th gear in pretty tight woods. It could probably run a bit cleaner.

if you never had the head off, then most will confirm that you get a much more consistent idle when you get squish corrected.
i'm doing the same to my 200 now.
alot of the 300's have a standart squish of aprox 2-2.3mm, wich is exessive.

you could get that sorted, you'll benefit from the extra torque and fuel economy aswell

[Jakobi]

Its true that reducing the squish helps stabilize the idle alot, but its not the issue here.

2 things I'm hearing/seeing.

1) It doesn't sound lean on the pilot or needle.
2) It definitely sounds lean at idle.

So.. If it was me I'd personally be looking for an air leak somewhere. It only takes a little crack in the intake manifold to allow it to race. You may have to take the manifold off the bike and hold it up to a light while manipulating it to be sure. Other than that stator side crank seal is next most likely candidate.

Or has someone just cranked your idle speed right up on the sly when you werent looking?

[Jakobi]

Also, does it race again now if you go and start it?

Do you run an inline fuel filter? Any chance it was just something jammed in the pilot at that moment?

[GMP]

Lean pilot ckt. symptoms, if it not real lean, sometimes don't rear their ugly head until you come down from RPM, and/or off high load, like at the end of a straight. I noticed this setting up my '12. I'd just make sure all is well with air leaks and fuel and try one up on the pilot.

[bukwheat]

Just got around to working on the bike as I have been down in the back for a couple of days...

I owe Jakobi and GMP a beer! Lean pilot was the correct diagnosis. I had removed the pilot early on, I could see thru it so I figured it was clear. I went down and talked to Bill who is my GG dealer at Dirt Bike Supply. He suggested the pilot jet also. He gave me a hand full to try, as I wasn't really sure what was in it. He gave me a 38, 40, 42, 45, 48 and a 52. I pulled out my old pilot jet which was a 42. Again, I looked thru it, could see daylight....I took an old high e guitar string that I use to clean jets with and ran it thru my old one, it wouldn't go all the way, alot of resistence. I took the brand new 42 and it would go thru with no problem....so....my old 42 had clogged enough to make it lean.

I put the 45 in and just got thru checking it out. After a good warm up and 10 min run, it comes down to normal idle rpm now.

Thanks, everybody that posted with any suggestions. If two heads are better than one, a whole forum can solve just about anything. Thanks!

[flybars]

I'm glad it was such a simple remedy. I learned something very valuable here. Thanks.