Is there such thing as a cylinder sleeve kit for a 82 gs550?

[JCT]

I am new at this.....
I have low compression on all my cylinders (about 85-90 psi) specs say limit is 92psi I went ahead and tryed a wet compression test and basically had the same results so it leads me to believe the problem is the head gasket or valve seats.
I went ahead and bought a seal-gasket and why not a ring kit , but this is an old bike and bought it in fairly bad shape, now I´m afraid that there could be something wrong with the cylinder walls (I am still waiting on the kits i have not yet oped up the engine but I used a borescope and even though i couldn´t really tell for sure what I was looking at it looked like rust) ...... my question is: Is there such thing as a sleeve for this bike and can it be changed or I can only buy a new cylinder block?
Thanks

And some advise in case someone is looking to buy a borescope ... pay extra attention to the focus length if it´s too far (more than 3cms) it really limits the places where you can use it

[60ratrod]

it depends on how many miles are on the clock. wait until you get the motor open to see exactly what the cylinders look like. chances are you may be able to get away with a hone and ring job

[tkent02]

Have you even adjusted the valve clearances? There can be be no compression if the valves aren't closing.

Are you doing the compression test correctly?

[Nessism]

1) Check/adjust the valves

2) Run the engine for several hundred miles

3) Check/adjust the valves again

4) Check compression: hot engine, throttle held wide open

[bwringer]

The compression test is just one piece of evidence; what else is there that makes you think the bores and rings are really worn out?

An awful lot of GS engines have been disassembled and/or scrapped needlessly because it's really hard to perform an accurate compression test, especially with tiny 550 pistons. You need a good compression tester (not Harbor Freight), a clear intake (best to remove the carbs) and good cranking speed (use a fresh, charged battery).

Many times an engine that's been inactive for many years shows lousy compression at first, especially if it wasn't running right before it got shoved to the back of the barn (tight valves are the most common cause of this). Once valve clearances, carburetion, etc. are sorted out and the engine runs a bit, the rings free up and the carbon around the valves loosens up, and compression returns.

What we're saying is, unless the engine has 120,000 miles on it or something, the bores are probably fine. Compression testing tells you very little for sure on a small air-cooled engine. Concentrate on going through the steps to get the bike running (valve clearances, carb o-rings, etc.).

[JCT]

Thanks...
There is no clear indicator that the bores are bad ... to be honest I really think the problem has to be the valves. My undurstanding is that by running a compression test you get to see the actual compression of the engine under regular conditions and by pouring a little bit of oil directly into the cylinders via the spark plug hole you get to measure the compression once again but you can almost guarantee that you will have no (or very little loss of pressure through the gaps between the cylinder wall and piston wall atleast for a couple of revolutions) Since I tryed the compression test "dry" and "wet" and have similar results I know the problem is not necesarily my rings .... Im almost sure is valves and if not it has to be the head gasket ....
Any way I will take your advise and chek, recheck valve clearence before doing anything else
I´ll try to work on the engine during the weekend and let you guys know any results
Thanks again

[JCT]

.... and just to know for future reference does anyone know if there is such think as a cylinder sleeve kit? ... I´m not buying one or considering getting one before further tinkering... just wondering

[tkent02]

No, but good cylinders are dime a dozen since they never wear out or anything. I have a stack of 550 cylinders sitting here collecting dust.

[Guest]

Do a leakdown test before you disassemble the engine.