Cylinder sleeve O-rings, purpose of

[78caferacer]

I'm about done redoing the top end of my 78 GS1000E. Did the old heat the cylinder block in the oven @350 trick and replaced a bad #2 sleeve like magic (yet another great trick I learned on this site!). In doing so, I displaced the O-ring around the sleeve and it is toast--as likely are its neighbors. Question: What purpose do these O-rings serve, i.e., why should I bother to replace them? I don't mind sending flatoutmotorcycles a little more of my hard-earned money, if necessary. Many thanks!

[Nessism]

Great question...I have no answer. I can say that I'd get some though. Suzuki had a reason, of some sort, and that typically is good enough to decide the path forward.

[49er]

They are fitted to prevent crankcase oil from getting between the liner/sleeve and the ali block. Ali and steel expand at different rates so it's possible that oil will get into that area. No big deal except your heat transfer/air cooling could be compromised without them.

[rapidray]

They are intended to keep oil from seeping up between the block & sleeve. I have NEVER put one back once I've removed them & never had an issue. No big blocks even come with them! I wouldn't even give a second thought to worrying about replacing them. Ray.

[chef1366]

They are intended to keep oil from seeping up between the block & sleeve. I have NEVER put one back once I've removed them & never had an issue. No big blocks even come with them! I wouldn't even give a second thought to worrying about replacing them. Ray.

That's what I've heard also.

[78caferacer]

Thanks

Great advice as always. Being prone to overdoing things, I'll replace them to be safe. Many thanks, guys!

[flyingace]

So...
You can replace the sleeves, pistons and rings with NOS items for a quick top-end job? No machine shop, oversize pistons, etc.?

[Matchless]

They are fitted to prevent crankcase oil from getting between the liner/sleeve and the ali block. Ali and steel expand at different rates so it's possible that oil will get into that area. No big deal except your heat transfer/air cooling could be compromised without them.

Very good question and a very informative reply! I never knew that, so now I do!
Thanks

[bwringer]

So...
You can replace the sleeves, pistons and rings with NOS items for a quick top-end job? No machine shop, oversize pistons, etc.?

You can't get the sleeves separately, AFAIK.

I'm frankly a little puzzled by the point of this myself. Is someone out there making cylinder liners, or are there certain models where the sleeves are available? There are a few models where the whole cylinder block is still available, like the '83 1100E.

[rapidray]

I can get sleeves all day long! Where do you guys come up with this stuff? STOCK is not all there is guys! Try L.A. Sleeve! Ray.

[49er]

Any machinist worth their salt can spin up replacement/or oversized sleeves. It's just a matter of choosing the right material.

[flyingace]

You can't get the sleeves separately, AFAIK.

I'm frankly a little puzzled by the point of this myself. Is someone out there making cylinder liners, or are there certain models where the sleeves are available? There are a few models where the whole cylinder block is still available, like the '83 1100E.

After looking at cost of the LA sleeves, I think machining to oversize is probably cheaper than replacing the liners. May explain why this alternative is not widely used.

If I had a single cylinder bike, I would replace the sleeve for sure. It's nice know that liners can be had if necessary.

[Nessism]

LA Sleeve quoted me $720 to have a GS1000 cylinder resleeved and bored to size.

I’m curious as to whether or not a liner could be removed from one cylinder and installed into another without messing up the ID dimensions of the sleeve. My guess is that it could be done but not without risk. Stock liners would most likely have a better chance of surviving this kind of work since they are thicker than liners bored oversize.

[49er]

You could swap liners. Stock ones would be thicker walled and would be more likely to retain their shape.
Blocks and sleeves/liners are machined to certain tolerances. Theoretically, they will all fit, but some will have a tighter interfernce fit than others. That is why Suzuki fits those o rings between the block and the bottom of the liners. Under certian circumstances/match ups, the fits could be on the loose side, allowing oil to seep into the gap between the block and the liners.
You can't beat making the oversized liners and then machining the bores on the ali block to fit.