Slight smoke exhaust KTM EXC-R 450 2008

i recently bought a 450 2008 and have only done 3 hrs on it and have notice slight intermitent smoke from the exhaust. Is this normal when running in the bike or should i have someone take a look at it?

At 3 hrs it not completely broken in yet.

I'd call it normal but not after 10 hrs.

Also, check the oil fill level. They've been know to be a little high from KTM.

Mine was high from factory and it would dump smoke like a airshow performer if I landed while brakeing from a jump. Changed oil and it stopped smokeing.

i have now done 12 hrs on my exc-450 2008 and still when i rev it hard in neutral there is, from time to time, slight black smoke from the exhaust. I have had the dealer service my bike and was told that the black smoke is just fuel. Apparently when you rev it hard in neutral the fuel pumps pumps up extra fuel which isn't used and exits the exhaust as black smoke.

is this correct?

Also when I have just started my bike there is slight white smoke initially when reving it which goes away after one ot two revs. I know this smoke is oil but is it normal even if it has only been left standing for 6 hours or so?

the black smoke is carbon from a slightly rich jetting (desired), white smoke on startup is fairly normal, you'll find that is simply unburned fuel, when left sitting some fuel does always leak into the carby and strait into the engine, which is why on a two stroke you always turn the fuel off even if your only going to stop for 15 minutes otherwise they flood, blue smoke is your engine oil burning.

the black smoke is carbon from a slightly rich jetting (desired), white smoke on startup is fairly normal, you'll find that is simply unburned fuel, when left sitting some fuel does always leak into the carby and strait into the engine, which is why on a two stroke you always turn the fuel off even if your only going to stop for 15 minutes otherwise they flood, blue smoke is your engine oil burning.

:thumbsup:

Waxy

Black puff is the accelerator pump doing its job!

With the stock crankcase and transmission vent lines routed into the carb you can get a bit of oil in there from time to time resulting in blue smoke. This is especially true after you lay the bike on its side, but can happen in normal riding as well. For some reason the trans vent will burp a bit of oil once in a while. You can just live with it or reroute the trans vent somewhere else.

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