It's an 09 klxs. I rejetted it this spring with 1411 miles on it. 116 main, third notch. and 2 7/8 turns out. This has a miss in it. The bike starts great, idles strong. pulls harder, Doesn't miss a beat under acceleration. But when i cruise around at indicated 30mph 3800rpm it misses. At times i can feel it miss at higher cruising rpms. I changed the plug, the plug looked clean. Don;t know much about reading plugs. It was dry and slightly brown. Installed a new plug and checked it yesterday. It looked dry, no build up. It didn't miss yesterday, but today it really started to miss alot more than it ever did. One thing i've noticed is my stock exhaust has a slightly brown ring forming about mid canister. The crome with all the warmings. Not real dark, but it's new. Need some help..... I guess this is what i get for trying to improve something.

 

If I knew anything which I really don't I would say you are running lean. Are you running a standard plug temp?

So its the can that is getting that hot?

 

The stock can has a catalyzer in it. If you went up a jet size, it may be burning up the unburnt fuel and creating more heat, creating the color change.

 

the color change i figure it unburnt fuel as you said. I just can't figure out the miss. I'm really afraid i'm running lean. I don't really understand moving the needle. Don't know what way to move the clip. Tmrw is the tinkering day. 9 24hrs shifts in a row so i haven't had much time to do anything. Only been drive to and from work. Other than poor mpg what are possible long term problems with running to rich. I ride alone in the middle of nowhere far from home. Don't want to push this obese bike outa the woods ever. Starting tmrw with cutting the side stand switch, then checking valves again. My left intake was borderline. .10 or something.

 

the color change i figure it unburnt fuel as you said. I just can't figure out the miss. I'm really afraid i'm running lean. I don't really understand moving the needle. Don't know what way to move the clip. Tmrw is the tinkering day. 9 24hrs shifts in a row so i haven't had much time to do anything. Only been drive to and from work. Other than poor mpg what are possible long term problems with running to rich. I ride alone in the middle of nowhere far from home. Don't want to push this obese bike outa the woods ever. Starting tmrw with cutting the side stand switch, then checking valves again. My left intake was borderline. .10 or something.

 

Did you remove the smog crap yet? The smog stuff directs some air into the pipe to INCREASE the exhaust temperature. The re-jetting may have made it worse. I would get rid of the smog crap first, and see how it affects the temp. Should drop it enough to keep the pipe from discoloring. As someone already mentioned - the CAT is designed to get real hot to burn off non-existant pollutants.

When I re-jetted mine, I removed the smog stuff and did the carb mods, leaving the stock exhaust on. Didn't have the issue you describe, but the pipe DID get pretty hot due to the restricted output. I did NOT notice it as being "hotter" than before (the re-jet) though.

 

Today, i called dynojet. Talked to them and i was told my jetting is fine. Anyhow, tore into it. Found the two vent tubes that run from the top of the carb to below the bike were burnt. basically plugged. Anyhow, replaced the hose, waiting on a test ride. I hit reserve today at 70. average mpg 47.

 

2 and 7/8 on the pilot eh? With stock exhaust. I am at 2 turns with an aftermarket exhaust. Try setting the pilot leaner.

 

A/F 2 7/8 out. Fixed the carb vents. Just my luck today, cold as hell with 30 mph gusts. Think it missed once maybe on my 20 mile ride, could have been a strong head wind. I did get it to miss once for sure on my way to work. Just one miss. Then drove around town for a bit, never got it to miss again. It's getting frustrating. Had enough trouble trusting the bike before, but now i have no faith.