lots of smoke out of vent line

[jaybo1]

i have a 81 gs850g and its smokin pretty bad out of the vent line that is hooked to the airbox. is it blow by and could the rings be stuck? just wondering cause it has sat for a few years. i don't have it runnin right yet but it is running. i checked comp. and i had around 95 on all four cylinders

[kamesama980]

Rungs would be a safe bet. that's about 2/3 what you should be getting on a compression test.

[gearhead13]

How many miles are on it? After you get it running for a while the rings might loosen up.

[jaybo1]

it has about 24000 miles, its been sittin for a while. so i bet the rings are stuck

[jaybo1]

it has about 24000 miles, its been sittin for a while. so i bet the rings are stuck

[blowerbike]

how is your oil level?
if the oil is over full then it will pressurize the crankcase and make it seem like blow by...
when carbs drain off and the gas ends up in the crank case it will make a bike smoke/blow oil out of the valve cover vent/air box.

[gearhead13]

You could put marvel mystery oil or seafoam in the cylinders and let it sit for some time. You can also put seafoam in the crankcase oil for a few hundered miles, then change the oil.

[SqDancerLynn1]

Some smoke is normal! Make sure to have the throttle wide open when checking the compression...First check the valves (adjustment) Then after the bike has run for at least 1 hour you can recheck the compression.....

[jaybo1]

i know some smoke is normal but it is a lot of smoke, lol

[Macguyver]

So that's where I left my stash!

[jaybo1]

i cleaned the carbs lastnight and set the floats and got it to idle on its own, left it idle for about 5 min. and the smoke seems to be thinnin out some and my compression has come up to 110 from 95 when i started. but i have a noise coming from the exhaust when i crack the throttle. its just a little tap sound. the motor sounds good and smooth. i can only hear the noise out of the exhaust. i thought maybe it was something in the muffler so i took it off and still had the noise. if you idle it up a little and hold it steady at certain RPM (didn't note what RPM) it will do it continously. what gets me is how noticeable it is out of the exhaust but can't hear it in the motor at all even with the old screwdriver in the ear trick. lol im starting to get concerned that i bought a bad bike. actually my brother from ohio sent me money to buy it for him so i hope i didn't screw him on it, lol.

[Nessism]

Marvel Mystery Oil in the gas works well to free the rings. I'd skip any thing in the oil. Needless to say you are just stabbing in the dark with getting the bike to run right until you do all the basic maintenance such as a carb rebuild w/new O-rings, new O-rings on the intake boot pipes, valve adjust, clean airfilter and seal air box with new foam, etc.

[blowerbike]

so dirty carbs made it have blow by and lower compression?
did i miss something

[jaybo1]

no, dirty carbs isn't causing blow by. i said i cleaned the carbs and got it to idle on its own so i could let it run a little to see if the rings would free up. i didn't say anything about dirty carbs was the reason for the blow by

[Steve]

Oh, somebody suggested checking compression after running for about an hour.
That's pretty good advice, but it should actually be running down the road for about an hour, not sitting in the garage, idling.

.