Rust and pitting on GL1000 cylinder wall

[LLRelease]

11/6/2024 update: The engine disassembly is complete, and the cylinders look good after honing. I measured the bore to make sure I didn't remove too much material. New rings installed. The old rings were stuck pretty good and may never have come loose. I am currently rebuilding the oil pumps.

I also stripped the bike down to the frame to repaint it. It's been a much bigger project than I hoped for, but I keep telling myself it will be worth it in the end!

The pictures below were taken before I removed all of the old head gasket material.

IMG_2334.jpeg

IMG_2335.jpeg

[NotSoLilCrippseys]

That cleaned up nicely.

Nice job. I wish you well on the reassembly.

[dontwantapickle]

I measured the bore to make sure I didn't remove too much material. New rings installed.

I am interested in this.
What were the cylinder measurements that you ended up with after the hone?
What rings did you use?
What end gap did you end up with?
Did you use a honing machine or a hand held drill and some stones?

[LLRelease]

Sorry for the delayed reply. I have been very busy with the holidays putting the bike back together after work and on weekends. The engine is painted and back in the frame.

I used a cheap dial bore gage to check measure the cylinders and a mitutoyo digital caliper as the reference. Cylinder 3 required the most honing in order to remove the pitting, and it measured between 72.008 and 72.020 mm after several passes. The piston OD is 71.94 mm. I purchased the ring set from David Silver Spares. It is an aftermarket set, and the quality seemed pretty good. I did have to remove material on many of the rings to ensure the minimum ring gaps.

[LLRelease]

5/26/2025 Update: My 79 is back on the road after a 24 year nap. I checked compression at 200 miles, and all cylinders were between 174 and 178 psi. The ball hone and new rings took care of the rust pitting in cylinder 3, and a friend helped me rebuild the heads. We recut the valve seats, replaced several valves, and lapped all of them. I also had the heads machined for flatness, and the shop took off 0.020”. I am keeping the revs below 5,000 for a break-in period. So far it’s running great.

[LLRelease]

Here is a picture of my 79 on the road again after the restoration. I am still sourcing a few bits. It took 11 months of weekends and evenings, but so far I think it turned out pretty well. I love the way it rides and sounds.

[Rat]

Nice work, awesome compression …

Gord

[NotSoLilCrippseys]

That's a gorgeous '79.

I'm more than a little impressed by the work you did to the motor!

[CYBORG]

Here is a picture of my 79 on the road again after the restoration. I am still sourcing a few bits. It took 11 months of weekends and evenings, but so far I think it turned out pretty well. I love the way it rides and sounds.

looks like a good canadate for Bike of the month running

[redglbx]

I’ll second Cyborgs suggestion! Very nice job there LLRelease !

[gltriker]

5/26/2025 Update: My 79 is back on the road after a 24 year nap. I checked compression at 200 miles, and all cylinders were between 174 and 178 psi. The ball hone and new rings took care of the rust pitting in cylinder 3, and a friend helped me rebuild the heads. We recut the valve seats, replaced several valves, and lapped all of them. I also had the heads machined for flatness, and the shop took off 0.020”. I am keeping the revs below 5,000 for a break-in period. So far it’s running great.

Excellent!
What are your intake and exhaust valves' lash clearance set at, please

[dontwantapickle]

Dang, that's a lot of work.

post a few more pics.

(I like blue oldwings)

[redglbx]

Don, I agree !

[Old Fogey]

Seems folks have had good luck with aftermarket provided their prep was good.

And that there says it all. Prep every thing correctly and install EXACTLY as the manual says, except (depending on which manual you have) the final torque figure is 45 ft/lbs. The Moly greasing is the MOST important aspect

[LLRelease]

Thanks for the kind feedback. I had lots of help from guys in this forum and a couple of experts who graciously answered my questions when I reached out directly (Bob Kramer and Erik Gellein).

Attached is another photo. The intake and exhaust valve clearances are both set at .006” per a recommendation on this forum.