Bike will not idle when hot

Idle issue
09 WR 250 R
I have been riding in the pasture quite a bit but not on highway.
I rode the bike about 20 miles on the Interstate Saturday. The bike seemed to have a stutter and was down on power. It would die when you stopped but would restart by holding throttle open.
Did some research when I got home. Added some Heet and some Stabil. I also change the spark plug.
Now the bike runs as strong as ever but seems to be idling to slow.
Cold the bike starts and will idle with no throttle but after it warms up it dies when you stop.
It seems like an idle adjustment would fix it.
What would cause the idle to go out of adjustment?
How do you adjust the idle?
Is something else going on?
I have also installed a clean air filter.

Thanks, Don

I think you answered your own question, adjust the idle. You need a phillips screwdriver, its on the left side of the bike, turn counter clockwise to raise idle.

I am having a similar problem. Once the bike warms up (after a few miles) it will die when idling at a stop. Rides fine. Usually dies after having stopped at a light for 10 - 20 seconds.

I did try the idle adjustment screw. Didn't see any improvement.

Try adjusting the "co". Just google co adjustment, there's a couple you tube videos and write ups on some other pages on how to do it so I won't get into the details. After my big bore rebuild it wouldn't idle for me once warm, I had to increase the co from 0 to 5 and that made it to where she would idle for me. The co mode basically allows you to adjust the rich/lean mixture at idle. You can drive around with it in co mode and adjust it on the fly. I got it warmed up, and just played with it until it would idle for me. Hope this helps.

I just left a message with my mechanic about the CO adjustment. Thank you! He did say he thought the bike smelled lean. Otherwise there have been no codes thrown. He did say that he is seeing air bumbles in the gas tank as it runs. Is this normal? He wasn't sure and I can't remember.

Not sure if I mentioned this in the earlier post. I just had the engine rebuilt. One of the main bearings went bad. Ran fine but sounded like hell. Got the rebuild back, put the engine back in and the idle problem started.

I was riding it home the other night after it had cooled down a bit and it no longer died at stops. The next morning, riding it a mile over to the mechanic's, it died twice at the same stop light. He's been able to replicate it over and over.

Any other thoughts are welcome. Thanks for he help.

Definitely sounds like what mine was doing. I think the co thing will help with that.

Bubbles in the gas tank? I can honestly say that I have never looked in my tank while running, but I may have to try it now  Do you have an aftermarket tank? Some of those have extra pumps to get the fuel out of the bottom. Interesting, but I don't see how that could be connected to the idling problem.

yaw wrote:

Not sure if I mentioned this in the earlier post.  I just had the engine rebuilt.  One of the main bearings went bad.  Ran fine but sounded like hell.  Got the rebuild back, put the engine back in and the idle problem started.  

Not to be skeptical or make you worry about this - but I have to wonder if this is the problem?  

I wonder if you're losing compression as the bike gets hot and mating parts start to change tolerances?

Your issue is ONLY when bike is hot?

Nothing is ever wrong when bike is cold and just started?

Idles fine until things get hot?  

I'm totally guessing here and really have no idea. But the engine rebuild thing has a fishy smell to it.

I have had it die shortly after starting it in my driveway. I'm pretty sure this happened when it has been warm out. I took it out the other night and rode about 80 miles. When I came to stops I would just crack the throttle a bit to keep it from dying. When I was returning home about 9:30pm it was getting cooler (oregon). I didn't crack the thottle at stops and the bike no longer stalled. So I do think it is temperature sensitive but to ambient temperatures. Hm. The next morning on the way to the mechanic (not that warm out) it died at a stop within the first mile.

The tank is an IMS 4.7. So the bubbles might have something to do with the uptakes from the wings. I would be curious to see if others with IMS tanks are having bubbling.

yaw wrote:

I have had it die shortly after starting it in my driveway.  I'm pretty sure this happened when it has been warm out.  I took it out the other night and rode about 80 miles.  When I came to stops I would just crack the throttle a bit to keep it from dying.  When I was returning home about 9:30pm it was getting cooler (oregon).  I didn't crack the thottle at stops and the bike no longer stalled.  So I do think it is temperature sensitive but to ambient temperatures.  Hm.  The next morning on the way to the mechanic (not that warm out) it died at a stop within the first mile.

That's like exactly what I used to get immediately following my rebuild. After hearing that I'm confident the co adjustment would fix you right up.  Is the bike at the shop now? If you want I can explain it step by step for ya. It's not complicated, probably take you about 20 minutes prep and about an hour of riding and tweaking.

If you don't mind I would really appreciate a step by step. I left my mechanic a message last night but didn't get a chance to speak to him today. I will contact him first thing in the morning to see if he looked into it. Otherwise I will take a crack at it. Thank you!

I had a really busy day today, got called into work  
I'll get you detailed instructions hopefully tomorrow afternoon. I just need to double check the steps to make sure I tell you correctly.

http://www.advrider.com/forums/showthread.php?p=16656209

These are the directions I used, I can't describe it any better than he did. Just press the "I believe" button and follow the directions exactly. You can get into the co mode with the ignition on, before you start it.  I'd suggest doing an initial adjustment of plus 3 or 4.  Leave it in co mode and go ride, once it's warm see how she's idling and you can tweak it up or down as needed. This mode also brings up the tac, but the odometer goes away and any mileage while in co mode will not be recorded to the odometer. I just kept doing laps around my block, pull in my drive and play with it each pass.

Took me about an hour total and made a world of difference. Good luck, let us know how it works.

Thank you!  The problem seems solved but no clear answer.  Originally I put the motor back in and it started to die at idle.  I charged the battery.  Then I played with the "idle screw" as mentioned in the manual which seemed to make no difference.  I couldn't hear the engine running any faster and it still died.  So the mechanic messed around and finally they adjusted the "idle screw" and it was fixed!  He said I had the air mixture too rich.  Hm.  Not sure how this happened.  It does seem to idle faster now.

So I'm going to drop by and show him that it is called the idle screw in the service manual and show him the directions you gave me.  Much appreciated by the way.  I will use them to check the idle speed.  The mechanic said he set it at 1,550 rpm.  

So ultimately it's a bit of a mystery to me anyway.

Thanks again for the help.  I am just glad to have it back and running.  Here's to another 22,000 trouble free miles!

Awesome! Glad you got it running.