Take a look at this cylinder, small hairlines by the exaust.

[SoFlo]

I just picked up this cylinder, and I was planning on running it on my '96 RM250.
The pic here is of my old cylinder, can you see that little fracture by the exaust port? I ran it like that for a bunch of hours, and didn't have any problems.

Now, the cylinder I just got has two fractures just like the one in the pic, one on each little bridge next to the exaust port. Any problems do you think with me running that cylinder like that?
And also, were 1996 RM250 motors sleeved? I'm almost positive that they are coated, but sleeved I'm not sure of. I see what I'd say could be a sleeve, but I'm still a beginner. With the pic I put up, does it look like it has a sleeve?

 

[SirHilton17]

That looks like a plated cyl...

I wouldent run it that way, Becuase if it brokw in the first place there is obviously some good amount of presure on it... so it will only get worse... And It could grab the ring...

Stay away from sleeves also... If anything get it bored out, and replated