3500' carb probs

I've read the charts and manuals, now I'm looking for some input. I've got an idle problem, sometimes it stays at the set idle, sometimes it stays higher by approx 1000 RPMs. Hot, cold, riding slow, riding WFO, doesn't seem to affect the problem, just random!?! I ride between 3,000' and 4,000. I've got a Yosh slip-on and a 160 Main, stock pilot and needle position, air screw 2 1/2 out, no snorkle. I haven't tried many changes yet, just got the bike. Thinking of changing needle and pilot, and adding holes to airbox, but looking for input first. Thanks, Troy

Thats a tuff one. Do you have a E or S. On my E at sea level I run 158 main, stock pri with the needle up one. I can ride up to 3000-4000' with no problems. I would drop the needle if I rode at higher elevation all the time.

Unless you have a real problem I would look at the cables and your twist grip

It sounds like a vacuum leak to me. Check your intake boots and carb clamps to be sure there isn't air leaking in.

Check the pull and push cables at the carb and inside the throttle grip. I will bet the return cable is frayed. It tends to bunch up at the carb and may even be kinked at the top. You have to pop the plastic cover off the side of the carb. There is a 10mm bolt that secures it behind the carb and two slots in front. Then you can see the throttle wheel. Reach in and feel the cable ends and be prepared to get stuck with some broken wires. I cut mine return off with side cutters and pulled it out from the grip end and left the housing intact. If your lucky the pull cable will work just fine without the push cable. Lube the pull cable by working some dry graphite down inside the cable housing with some liquid wrench or other very light oil or cable lube. Don't bother replacing the plastic shroud. Toss it in the box with the snorkle and stock filter. The old return cable makes a great brake snake by using the crimps that can be bought from most hardware stores.

If you do even shallow water crossings now is a good time to seperate the two breather hoses that cross over the carb and hang down below the bike with the others. Run then back under the seat next to the air intake. They may need to be cut shorter. That will help to keep the bike from stalling in water crossings. The 2 clear hoses are taped to the other two on each side of the carb. Cut thru the tape with a razor knife and pull the correct one up with long needle pliers. Be sure to pull the one up that cross over the carb. It can all be done with just the tank and seat removed.

I agree 100 %. Check the Vacuum lines and cables. If the cables are new they might be to tight. Also if you may need to adjust the air screw to the best lean idle after the bike warms up.

Thanks alot guys, I'm gonna look into all of these suggestions. Troy

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