Cylinder Head is off, Now What?

[Don-lo]

I agree with nessism: the rings are matched to the cylinders now. You have good compression. Slap it back together and go. If the base gasket starts to leak later, you can have the rings ready when you go back in. You can also do a total head cleanup then. You understand the top-end removal process, so doing it again will be much easier.

[Hank.SD]

After much deliberation I decided to replace my valve seals as well. Another $50, but I started to think about that 27 year old rubber and figured it was wise.

[blokv1100]

Interesting thread.

I am in the middle of this project at this very moment.

This is my first time doing this.

I broke her down Easter weekend (see attached photo)

I picked up the new gaskets yesterday.
I was able to get the cylinder jug down over the pistons last night. Wow, that was fun (NOT). 4 arms recomended, I only had two at the time.

Taking my time, when I get pi*sed, I stop and then try it again the next day.

I'll keep you posted on the progress.

[RyanBiggs]

Awesome, this is gold, thanks for your collected knowledge.

To answer a couple of questions, the engine has just over 30,000 miles on it, so the problem is primarily age as opposed to wear. I believe the oil leak was from the o-ring part of the gasket around the front right corner stud, around which appeared to me to be an oil passage. But maybe I'm crazy about that. It doesn't appear any oil has been getting into any cylinders.

I had just about decided that at least I knew I'd be pulling the cylinder block off, although Don-lo's argument sure is tempting. Knowing my luck I bet it'd leak though, which gives me pause. I've noticed after tapping the head off the positioning dowels, that oil appears to have escaped from around that base gasket...

If I take the cylinders off and manage not to tear anything up, I'm tempted based on this discussion to keep the old rings.

From an article in the August 2000 issue of Motorcyclist about the GS1000S: "When idling below 1000 rpm, most two-valve GS engines emit a metallic slapping or knocking sound. This is caused by the cam-chain design; at low revs, the chain slaps a bit. It's completely harmless, and has a simple cure: ignore it." I swear I had heard about this previously as well. Am I really the only one here with this quirk?

[Big T]

Since it's supposed to idle at 1,200 rpm, I wouldn't worry about it

[Don-lo]

Ryan, the lowest gasket (under the cylinders) is the base gasket. If you have broken that loose, then you will need to pull the cylinders, scrape off the old gasket (difficult, usually), and replace base gasket, teardrop o-rings, and big o-rings around the cylinders. Your original post said the oil leak was in the head gasket, which is the one above the cylinders. As blokv1100 says, it takes attention and patience to slide the cylinders back on, so be careful. Since your compression is so good, I wouldn't mess with the rings or honing. These bikes are keepers, so I would just ride it for 3-5 years, at which time a 1085 piston kit would be a nice upgrade.

[RyanBiggs]

Thanks again everyone. Yeah, speaking of o-rings, just about all of them on this bike that haven't been replaced are hard as a rock, so I'm sure the ones at the cyl. base are no exception. I'll bite the bullet and get an extra pair of hands to help me pull the cylinder block, freshen all the gaskets and o-rings, and hopefully put 'er back together with my good ol' piston rings. I've had this bike for 10 years now, so this is sort of part of an anniversary overhaul. I'll be keeping it for many more!

[first timer]

Just a heads up , when you pull the jug 9 time out of 10, the channels of the inner studs will be caked with road grim and dirt, making it a bit of a challange getting the jug out. just take your time wiggle things up down left right and spray the holes alot with wd-40 or the like to loosen up the grim. That should help make the jugs slide up easier. Also if you have a shop vac to suck up as much crud as you can while you are doing this it helps keep it from falling in the engine. Just take your time and be vigilant of the grimp so it doesn't fall into the engine.

[tkent02]

Just a heads up , when you pull the jug 9 time out of 10, the channels of the inner studs will be caked with road grim and dirt, making it a bit of a challange getting the jug out. just take your time wiggle things up down left right and spray the holes alot with wd-40 or the like to loosen up the grim. That should help make the jugs slide up easier. Also if you have a shop vac to suck up as much crud as you can while you are doing this it helps keep it from falling in the engine. Just take your time and be vigilant of the grimp so it doesn't fall into the engine.

If the engine is out of the frame you can flip it over so the dirt falls out instead if into the engine.

[tomcat24551]

From an article in the August 2000 issue of Motorcyclist about the GS1000S: "When idling below 1000 rpm, most two-valve GS engines emit a metallic slapping or knocking sound. This is caused by the cam-chain design; at low revs, the chain slaps a bit. It's completely harmless, and has a simple cure: ignore it." I swear I had heard about this previously as well. Am I really the only one here with this quirk?

Motorcyclist is probably wrong on this. It's very likely cam endfloat, where the thrust rings on the cams hit the head where the cam bearing caps are bolted to the head. 49er has designed an ingenious fix for the problem and if you PM him he'll probably send it to you. Since you have everything apart, now's the perfect time to cure the problem!

The job does require some accurate measurements and a good machine shop to do some work on the bearing caps.

The fix he's come up with should be made a permanent part of this website, like the carb tutorials!

Tomcat