KLX250S Smoking Material Under Exhaust Clamp | GTAMotorcycle.com

KLX250S Smoking Material Under Exhaust Clamp

jonpurdy

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I've got a 2009 KLX250S which I'm very happy with. Other than getting it started in the cold, it's fantastic.

When starting it up today I noticed smoke coming from the end of the exhaust header. It looks like there's a material between the header and pipe connected to the muffler directly below where the clamp is.

Is it okay that this started smoking today? It smoked for about ten seconds then stopped. I took the side covers and seat off started it up again. Smoke for a couple of seconds from the same spot then stopped.

Should I replace the material? Does the bike come stock like that? (I purchased this bike used.)
exhaust%20header.jpg
 
my money is on an exhaust leak that you saw in the cold. You can replace the packing ring for <$10, or just live with the leak. I would be surprised if it was leaking enough to cause any problems.
 
Smoke or is it really STEAM?
Have you tried to tighten the clamp?


I will try that. I noticed that one of the bolts that hold the exhaust in place is missing. If that came out recently it could put additional pressure on the clamp and perhaps cause extra heat to touch the packing. But that's just a theory.


I'm going to go over the bike and check to see if any other bolts are missing and then order replacements.


my money is on an exhaust leak that you saw in the cold. You can replace the packing ring for <$10, or just live with the leak. I would be surprised if it was leaking enough to cause any problems.


I'll replace the ring when I winterize in a few weeks, just to be safe.


Thanks for the help, bitzz and GreyGhost!
 
I don't know your model specifically but can guess it's an exhaust leak as mentioned. When running the engine put your hand around the connection, you'll probably feel the exhaust leak. Previous owner might have had the muffler off and was not careful on install. The mesh gasket could be distorted easily. Before installing muffler you need to run your finger inside the gasket to make sure it's pushed down and no strands are proud. GENTLY!! SHARP EDGES!! High temp. silicone could be applied as well.

The hard starting could be symptom of leaned out fuel screw from factory. That's a little more involved but do-able for beginner mechanic. Search or ask if you need.
 
I have the same bike. I really like it, its a ton of fun! I have never experienced the smoke problem you describe. If you want to see my stock setup PM me. Maybe that'll be of help to you. Always nice to meet a fellow rider with the same bike!
 
Replace the missing bolt and tighten that clamp, I doubt you need to replace the gasket.
 

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