Topic: CB500 Piston and cylinder questions

[Priscbs]

I got my head and cylinders off today to find what was suspected, frozen rings.  The pistons and cylinders themselves look good but I have broken a few rings trying to get the off.  The bike only has 10k miles.  So here are my questions:

1- Is there anywhere you can buy just rings and not the whole set (I already know what I SHOULD do but I am sure someone will tell me anyway;))?

2- Are the 555cc kits on ebay any good, cuz the whole kit is cheaper than 4 new sets or rings.

3-  I have heard over and over again that the only difference between the CB500 and the CB550 is the cylinder/piston.  How true is this?  Would 550 jugs and pistons fit the 500 head and case?  I did some part number research, and it looks like the heads, head gasket, and base gasket are all the same.

I just want to know what all my options are at this point.

[FunJimmy]

To the question regarding 500 vs 550 compatibility, the answer is yes. The difference is bore. You can easily install a CB550 cylinder and pistons and have yourself a 550cc engine.

I recently purchased the 555 big bore kit for the same reason. Price! Everything is new and cheaper than stock rings alone, but the oil control ring is a one piece unit and the factory 3 piece unit is presumably better. Guess I’ll know soon enough.

Good news is that used CB550 cylinders and pistons are plentiful and cheep on feebay.

Later

[SteveD CB500F]

You can buy the ring sets from several places (David Silver has various sizes at the moment I believe). You'd need to be sure which size you have, but with only 10k miles I'd assume that they were the originals (ie std size)

[bryanj]

Std ring sets are £13($26) per Piston set at Dave Silver and a gasket kit £39 ($80) then you got shipping and possibly customs duty.

You CANNOT get individual rings.

The 555 set will fit but you got to pay for 4 rebores and last time i tried to fit 550 cylinders to a 500 the holes in the crankcase were not big enough, late cases may be bored different--dont know.

500 complete cylinders with pistons seem to be common on ebay but you dont know how good the pistons/rings are till you get them.

One last thing is Dave Silver did do piston kits on standard size for about £20 if he has any left and considering the price of circlips, which HAVE to be replaced if removed, and the wrist pins was a very good deal. You would have to email him on those

[crazypj]

:1- Is there anywhere you can buy just rings and not the whole set (I already know what I SHOULD do but I am sure someone will tell me anyway;))?

2- Are the 555cc kits on ebay any good, cuz the whole kit is cheaper than 4 new sets or rings.

3-  I have heard over and over again that the only difference between the CB500 and the CB550 is the cylinder/piston.  How true is this?  Would 550 jugs and pistons fit the 500 head and case?  I did some part number research, and it looks like the heads, head gasket, and base gasket are all the same.

I just want to know what all my options are at this point.

1. You can't buy individual rings, only sets ( I think total seal are different but they are automotive and very expensive which defeats the purpose)
2. haven't looked at a 555 kit but it sounds like a 0.5mm OS for 550?
3.The 500 and 550 share bore spacing, generators, cylinder heads.  most parts can be fitted with some work. The transmission is stronger on 550 (but second still fails on some of them) It has a miniature oil pump built into output shaft bearing to keep things happy ( I don't think its shown in any manual?)
If you have to bore cases its a major strip down (but worth it as you can bore for 650 liners and fit them at a later date)
PJ