Here I go with the engine rebuild....

[goat]

Well, this do to a problem I posted about before, but I'm starting a new thread because this is a question that doesn't specifically have to do with vibration. I posted the images as links becuase they are larger images. I want to make them smaller but I just haven't sat down and figured out how with the software I have yet.

I started to take my engine apart today. So far I haven't noticed anything major, but I haven't gotten into the crankcase yet. There are a couple of things that I am not sure about, however.

Is the tensioner blade supposed to be be off to the side like this? Is this just because I had the tensioner out already?

There seems to be a lot of what looks like sand around the studs coming out of the crankcase (is that the right term?) Is this normal? I was a little alarmed at how dirty the pistons were, too (not the fact that they were dirty, but the thickness of the layer and the grey stuff) Could this be because the bike has been running lean for a while (before I bought it, who knows how long)

I don't have any pictures of this, but is it ok to have small chips out of the corners of the camchain tensioner blade and guide? The surfaces are smooth for the most part, but there are little chips along the edges of the face that faces the chain.

Anyhow, I am going to split the crankcase tomorrow or monday and inspect the crank, the end of the tensioner guide blade and the bearings.

[goat]

I should have asked this earlier, but does anyone want pictures of anthing while I have my engine apart? I can't really think of many reasons why, but let me know soon if you do.

[Blueknyt]

do a step by step pic posting of engine rebuild, would make a good write up.

[Bob Broussard]

So far everything looks very normal.
The inner studs are exposed when the cylinder is on, so it's normal to have dirt and stuff around the base. The pistons look pretty good. No shiny areas around the edges on top ( meaning it wasn't burning oil).

When you split the cases, Don't loose the 2 small rubber blocks that hold the chain tensioner guide in place. They will get stuck to the case when you split it and could get lost. Or could fall into the area where the guide sits and be covered by oil in the crevice.

[goat]

It took me a little while to figure out what the rubber things were for. Didn't lose them though, thanks.

I am taking pictures as I go, but I am not sure that I took enough at the beginning to make a "teardown manual". I'll find out when I'm done, I guess.  :lol:

I have a question about loctite. Where should it be used and which strength? I did a quick search through the archives and didn't find anything. My manual does not say anything about loctite.

[Bob Broussard]

The flywheel bolt gets RED(so called permanent) loctite, but you won't be messing with that.
Other than that you would only use BLUE. And there really isn't anything that needs it.
For racing I only loctite the chain tensioner bolts. The drain bolt and filler cap are safety wired. That's it for the motor.

I would take the carb manifolds off and replace the O-rings. Then use BLUE loctite on the manifold bolts.

[goat]

OK, more pictures and questions. I seem to be full of these:



This is the front of the clutch housing. The cracks concern me. Is this normal, or is this going to be a problem?



The back of the enclosure



one of the main bearings. It's not a great picture, but I  think I can see a few particles imbedded into the material. My thought is just to replace them all, but I was wondering what other opinions were out there.

Let me know if the pics aren't showing up. My server was timing out for a little while, but seems to be working now.

Thanks for the inout. I really appreciate it

[Bob Broussard]

Clutch hub is normal.

All bearings should be replaced.
Get some Redline assembly lube. Comes in a flat round jar type container.
It's red. Put a good amount on all bearing surfaces (including cams) as you assemble the motor. Cylinders should be honed and new rings installed.
After honing, clean cylinders real good. Then with a paper towel, wipe a thin coat of 5wt oil in the cylinder. Put regular 10/40 oil in motor for break in.
No synthetics for now

There is a letter/number coding on the crank and cases to figure what color coded bearings you need. Your manual should show you where to look and have a chart for the bearings.
The rod bearings come 2 to a box (1 box for each rod).
Crank and CB bearings (same thing) come 1 to a box. So you need to order 2 boxes for each bearing journal.

[perfdrug]

when i tore down my engine i took pics with the goal of writing a walkthrough
but my clymers is damn good already, so i never followed through. aside from the cross-referencing, there's no way i coulda done a better job than the manual.

[goat]

I agree with perfdrug on the manual. There are a few things that would have been helpful to know before I started to tear apart the engine, but I am not sure I could do a better job than the manual does (organization, probably but content, no). I'm thinking more along the lines of a "uide to the guide" with a list of tools, parts and other supplies I needed along with some tips and a few pictures. My thought is that anyone serious about rebuilding probably has a manual already.

How neccisary is the cylinder rehoning? I took everything apart to clean the metal bits out if everything and I was hoping to get away without rehoning the cylinders and replacing the piston rings. Is this a bad idea?

[cernunos]

Sh** goat, yer this far into the thing and yer wonderin' whether to re-ring? Actually from my experience and some other engine builders I've worked with, it's the oil rings that will give you the most problem when not replaced. They don't take kindly to being compressed then release and then re-compressed later. If your cylinders and pistons look O-K (no taper, out of round, wrist pins O-K, no ring-land wear, etc.) then you could just de-glaze the cylinders and clean up pistons put in new rings and go to town. And on this type of "overhaul" you wouldn't need to follow the original type of break-in. Some people may disagree with me but I've overhauled lots of motors and have yet to see any problems with them. New ring set and gaskets and cam-chain guides, maybe rod-bearings with a polish of the rod journals and you'll be good to go. Oh I'd have the head re-worked too. Don't you just love this GS500 and this forum? I do.

Cernunos

[goat]

I am a college student though. My budget is stretched pretty thin for the parts and tools I have already paid for. Hence the hope that I don't have to spend too much more $.

I think that I'm going to hone the cylinders and replace the rings. However, I do not have the $$$ for head work and I don't think I want to do that myself. I think I'm just going to clean it and put it back on. It was running fine before I took it off and I only have 6k miles on it.

Can I use an auto piston ring compressor, or do I need to find one that is ment for a motorcycle (if there is such a thing)?

[goat]

I'm so close to being done, it hurts. I spent the weekend getting high on cleaning solvent in the garage. If I ever do something like this again, I'm going to start the fan BEFORE I start.

I just have to put the front sprocket and chain on, attach the negative battery lead and tune the carbs. I just hope that there are no bad noises when I start  her up.

I would have finished this weekend, but I decided that it would be a good idea to wait until I was 3/4 done before I tried to put the camchain and tensioner blade back in. That involved several hours of cursing and re-doing work. I take most of the blame on that one, but the instructions in the haynes manual are a little cryptic in layout. Is the clymer manual laid out any better?

Where is the negative battery lead supposed to go (yes, I know it goes on the battery, i ment the other end that attaches to the motor)? I just can't remember which bolt its supposed to go on.

[Kerry]

Where is the negative battery lead supposed to go (yes, I know it goes on the battery, i ment the other end that attaches to the motor)? I just can't remember which bolt its supposed to go on.

See the thread Engine ground.

I don't think it really matters which bolt you attach the ground wire to, as long it's connected to the frame.

[BadBatzMaru]

no it didn't matter in the end... I bolted it somewhere else. worked fine.

[Trwhouse]

Hi,
For this engine with only two cylinders, a piston ring compressor is not really necessary.
When I worked in a motorcycle shop, the trick we used was to use a soft wooden popsicle stick to push the sides of each ring gently so that the piston would eventually slide up into the cylinder. Do one ring at a time and as it allows the piston to slide into the cylinder, work on the next ring. Be gentle and it will only take a few minutes. The soft wood of the popsicle stick won't damage the sides of the rings if you are GENTLE.
Also, be sure to stagger the ring gaps! This is important to keep the cylinder charge of fuel/air or exhaust from leaving before its time. Check the manual for the correct stagger, but usually it is 120 degrees for each gap.
Good luck, and have fun!
Yours,
Todd