After 58K and 30 years on the original chain, I decided to put on a new one. Here's a photo of the original. It's 630 chain on my 79 GS1000. One of the first bikes with O-ring chain. Back then, they were worried what chain lube would do to the O-rings, so I used 80 weight gear lube. Notice the 130 tire. That was a wide tire back then.
Yeah, that's a Works Performance shock. I also wanted to change the sprockets. Problem: How do you hold the new sprocket when you have to tighten the nut to 70 lb/ft. I used my clutch tool to hold the sprocket. The clutch tool is a vice grip with tangs for holding the edge of clutch plates while tightening the bolts.
That was the first time in 30 years that my sprocket cover has been off, so don't mind the grease. But you can see how the tangs are holding the sprocket teeth.
Here's the new DID O-ring chain and new rear sprocket. Good as new and ready for another 30 years. Notice the master link. Now that the chain doesn't make any noise, I can hear all the other noises that the bike makes.