stuck pistons

[mflynn]

i just got a cb77 from my neighbor who left it for me when he moved.<br /><br />i couldn't turn it so i removed the plugs and put in marvel oil and let it soak. i still couldn't turn it so i pulled the engine off and took off the top w/the valves. <br /><br />i can now see the pistons but can not get them to move despite using a mallet. <br /><br />is my next option to disassemble from the bottom? <br />or ?<br /><br />where do you guys find parts for these things? i will need a bunch - including mirrors, brake hand lever, and metal component of the seat as the original is too rusty to recover.<br /> <br />sorry about my lack of correct terms - i am a bicycle mech. and this is my first motorcyle/engine experience.<br /><br />thanks,<br />mike

[kustommusic]

mflynn, Wow that is really stuck! Still a great project. How long have you soaked this thing? I think in many cases it could take a week or two. If its been more than that you may need to get drastic with it. The mallet is OK but by now you gotta figure it's gonna have to go to the machiene shop once you do get it apart,for boring etc. and youll want new pistons and rings. Latley I've seen pistons and rings on e-Bay for cheap, might be the way to go if you can trust a stranger. There are also parts available thru vendors here on this site. And a new auction here that is just starting up. But best of all your on a great site with enthusiasts willing to help. Just a side note, dont plan on removing the connecting rods from the crank during your dissasembly, that is not for an amature. Also do your self a favor,get a shop manual! Good luck, Steve Greer

[perryT200]

i had one stuck. soaked in marvel 3 day, beat it with a pointy 2x4 and a ballpeen hammer. it never moved.<br /><br />heard that the acid in coke cola would help. tried that for three days, beat the pointy end flat and it still didn't move.<br /><br />took it to a machine shop and for 3 days they heated on and off with a torch and poured penatrating oil. finally, when i wasn't there they used a sledge and brass rod to start it moving.<br /><br />it had sat for 5 years with a rotted off exhaust and the moisture had rusted the rings completely to the cylinder walls. honed to one size over and a rebuild with new gaskets and seals, and it runs.<br /><br />best for parts is <br /><br />ebay<br />ohiocycle.com<br />junkyards (breakers)<br />