82 csr 305 smoking out the exhaust

It has 2000mi my guess was it has sat since the mid 80's.

Starts and runs great

The only problem besides the smoke is the bowl gaskets are crap and it seeps small amounts of gas on the bowls.

I checked the plugs and they are clean and normal. The oil is clean enough to make fries with and yet it billows out huge amounts of smoke when started which lessens a little as it warms up. The smoke Comes out both pipes and varies which pipe is smoking more back and forth as it runs.

I am guessing it must be a carb issue possibly a blocked passage forcing excess gas into the engine. But it runs perfectly and idles and starts great. It also must be the same for each carb as the smoke comes out both sides but changes off which one is blowing more smoke. I have ordered new bowl gaskets but was wondering if this is common for 305s and if there is any specific parts I should clean or check.

I did run some fuel cleaner through the bike and change the oil with no effect.

Thanks for your help.

26 year old valve stem seals might be your problem. Do a compression check, see if your compression is still good. if it is then its probably not the rings. What color is the smoke? if its gray then its oil if its black then its fuel. that should help you figure out where to look.

Matt-