Freeing stuck piston rings

[motogtp]

After a lot of great input from the forum I am pretty sure I have stuck rings. The bike runs well but fouls the plugs (I am running NGK D7EA plugs) after about 60 miles. Is it possible to loosen the rings without taking the engine apart? Say maybe a tablespoon of Mystic Mystery Oil (or whatever that stuff is called) in each cylinder and let it sit for a few days/a week? I can get the front of the bike elevated so that the piston tops are level and the oil should distribute around the circumference. Bad idea or worth a try?

 

[bitsa750]

I Freed gummed rings on Cbr 250rr. n.o 4 cylinder had very low compression ,but it was a low mileage engine,had been sitting afew years, suspected gummed rings.
Put no.4 at TDC, filled cylinder all the way to top of plug hole with spray carby cleaner and found it took over an hour to drain away.Added oil down plug, Cranked the engine for a minute on starter. Then did it again, took less than an hour to drain. Kept doing this till the solvent took less than 5 minutes to drain. Changed oil and fired her up, good as gold, even compression again!

 

[motogtp]

Thanks Bitsa. I took the plunge. Drained the oil, left the pan plug out, and filled the cylinders with Marvel Mystery Oil. I have been watching the oil drops for more than a day and there is definitely carbon being pulled out. Might try your method for a final cleaning before I recheck compression and get ready to fire her up. Also, Lesson Learned - make sure you elevate the front end enough so that the oil doesn't run out an open exhaust valve into the pipes!