81 Gs850G parts bike blowing black smoke on decell vavle stem seals?

[Guest]

My 81 parts bike had a lot of problems sat for over 9 years, I spent a week on this thing, and its running really well now, electrical problems sorted out, fuel system sorted out.

At this point I'm not sure how much I want to do for a spare bike (my nice 81Gs805G is mint and insured). The exhaust leaks bad, and the air filter housing is not off a Gs850G, off a L or xl model maybe, all the foam seals are pooped...

But I'd still like to determine the shape of the engine, it has 78,000kms and was seized, from sitting but broke free easily with wd-40. It starts really easy and runs great. But blows black smoke free rev in neutral from 5500-9000rpm out both pipes. Smells like burnt oil. And the clutch is slipping from 5000-9000 under hard acell

How do I know if its rings, valve stem seals, or running rich that's making the smoke? I'm pretty positive its oil since I smell burnt oil.

My other mint bike has 46,000kms and doesn't smoke on rev in neutral, but I do smell oil a bit, so its hard to tell wouldn't it be blue some if its oil related?

I have both a compression tester, and leak down tester, now that I've burned a half a tank of gas, I'll perform both tests. (I wanted to reseat the valves and rings first by running it.

Anyway my brain is always going off on a tangent

All I want to know is;

-How to test for bad valve stem seals?

-Sure fire way to determine if the smoke is fuel or oil?

-How to or link to doing valve stem seals with the head on the bike?

Thanks for the newbie thread links, carb links, and all the help in the electrical section guys Really appreciate all your advice

[Nessism]

Be sure to adjust the valves before putting any miles on the bikes or checking compression.

BTW, black smoke is from extra gas. White/blue smoke is burning oil. Water vapor burn off is white as well but smells different. And speaking of smell, any oil that may have dripped onto the exhaust system will create some burned oil smell but that will work itself out fairly quickly with use.