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blue smoke at idle is too rich. I suspect. Low speed jet, if it's that bad. Go smaller.

But if it's stock jetting, I wouldn't think that's the actual problem.

I'd look for a leaky fuel shutoff or fuel selector first.

Something that's wetting the cylinder with too much fuel.

edit: Or my favorite... a dirty air filter causes too much fuel to be drawn.

giving a fuel-air ratio heavy on the fuel side.

Noticeable when engine is cold (especially with choke on).

Edited by ReconRat
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Just smoke on start up?
blue smoke at idle is too rich. I suspect. Low speed jet, if it's that bad. Go smaller.

But if it's stock jetting, I wouldn't think that's the actual problem.

I'd look for a leaky fuel shutoff or fuel selector first.

Something that's wetting the cylinder with too much fuel.

edit: Or my favorite... a dirty air filter causes too much fuel to be drawn.

giving a fuel-air ratio heavy on the fuel side.

Noticeable when engine is cold.

Black smoke when revved while cold. Uses oil, but not a lot. Gump suspects valve seal. Bike is an 03 of unknown hours. Buddy bought it about 5 years ago and I got it off him.

I am sorta concerned that it is too lean causing blow by at the ring but there is no gas in oil.

Hell, could be a dirty filter.

Runs strong, starts right up and purrs. Maybe I'm just paranoid.

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Yeah, black is just lots of combustibles. Quit revving it cold, lol.

Gump is probably right. Funky at start up, and warming up makes it stop.

Basically if it used to run ok, then it's not something in the carb unless the carb clogged up with varnish or broke, which would be more of a lean condition. That could draw oil, but it wouldn't just be at idle. Again, reading the plug would be a good idea. That and a compression check. Both wet and dry. Those items will pretty much isolate what it is.

Checking the carb isn't a bad idea, there's often something to make better. But later.

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