Hello All, I recently inherited a 81 250R that I really want to run again, stock cylinder is no good so what did i do? Well, I have one here in near perfect condition off a 79' CR 250, does anyone know if it will work? It looks exactly the same and uses the same piston and ring but I am not sure if I am missing something here. Any help would be greatly appreciated..Thanks

 

What exactly is wrong with your cylinder now? I'm not exactly sure about 79 cylinder working on your bike. If everything matches up then I don't see why not. If you keep your eyes open you can usually find pretty good deals on cylinders for your bike on ebay. Do a search for 81-84 250R and see what you can come up with.

 

To answer your question, the bike was given to me b/c my brother-in-law attempted to do a piston and ring..well, he did it alright, he didn't read any instructions I guess and installed (Wiseco) the rings incorrectly (paid no attention to the locating pin) and from what it looks like he forced the piston in and severely gouged the cylinder (i mean bad) and it's already bored .40 over so here I am. I actually purchased the cylinder used from someone b/c it looks exactly the same and uses the same piston and it's in very good shape w/ a .10 bore and very clean. The thing is, the original head's 6-hole pattern is just slightly (maybe 1/16") off and this got me wondering what else, if anything may be different. I searched for awhile for the 81' cylinder (including ebay) and didn't find anything so I got this one. Was just wondering if anyone had any suggestions, that's all.

 

Yeah I've never been big on swaping parts between different years and different model (dirt bike/atv) unless I new 100% that things were interchangeable. I mean I guess if the intake and exhaust line up and the piston skirts are the same then it should work. Have you considered just having the origanal cylinder re-sleeved? I had an '83 cylinder laying around a while back. I wish I new where it was, I would just sell that to you super cheap. I'll take a look around. Good luck.

 

Well I was able to find the specs on the 79' and the 81' and it looks pretty good, the Bore & Stroke and the Displacement numbers are exactly the same too so I'm gonna give it a roll. If it blows up I will just drive my slow 400EX [img]i/expressions/face-icon-small-smile.gif[/img]

 

Awsome, good luck and let us know how it works out for you.