Another update. After a ride, as the bike was rolling while pushing it around, I noticed a clicking from the front sprocket area. I was worried that the front sprocket came loose again, but I pulled the chain cover and it was still tight. I then figured maybe it really was time to replace the chain and sprockets.
Looking at chains, it is true that the selection of 630 chains is pretty limited. But I wasn’t really ready for the 530 swap. I ended up with an EK o-ring chain and JT sprockets. I also considered going to the earlier and later ratio of 15/35, but I decided to just stick with the stock ‘78 15/33.
Unfortunately, I lost my sweet workshop and I’m back to working in my little garage with no power. Anyway, it’s still better than no garage. It’s just real disappointing after working in such a nice space.
The EK chain is made in Japan, which is nice. The JT sprockets are made in Thailand. They seem fine. The only thing I didn’t like was the JT rear sprocket has round cutouts, while the stock rear has oval cutouts. The round cutouts expose a part of the hub that was previous covered by the sprocket. So that bit of unpainted aluminum and the pockets below the sprocket will now be exposed to the elements. A new place to collect gunk and debris.
The other thing I’ll mention is that those dog-bone lock-tabs are really a big pain in the neck. The tabs were bent up on 2 sides of each nut. That’s 16 tabs to bend flat and then bend back up for new sprocket. It took forever. I’m guessing they went to flange or lock nuts not longer after ‘78? If so maybe I should switch to those newer fasteners next time.