Here's an update to the WD-40 experiment. After 8500 miles since new, I've adjusted the RK chain on the 750 for the first time since the adjustment I did at around 200 miles. It didn't take much, just turned the adjuster bolts two flats. The sprockets look good and chain still runs quietly. The nice thing has been how clean everything is staying. So far, so good, so the experiment continues.
How about an update, year or so later??
Two years since I posted an update on the WD40 experiment already. Jeez, time flies.
The chain and rear sprocket are doing fine. A couple of months or so ago, when the chain/sprocket set (RK 530 o-ring/Sunstar 18/48) were at about 16,000 miles, I noticed I was getting increasing noise from the front, rattling a little when I pushed the bike with the engine off. When I checked, the countersprocket was worn quite a bit. For obvious reasons, the countersprocket wears faster than the rear, but my impression was that the wear was more than I used to see when I used Maxima chain wax. Not a lot more, but still more wear. I had another Sunstar countersprocket laying around with about 1000 miles on it, so I swapped them out. At that point I went back to using Maxima chain wax.
The RK chain and rear sprocket now have a little over 18,000 miles on them now, and it appears they will go a lot farther. I have been getting 20,000-25,000 from the same combination on this and other bikes in the past, and these will probably go that far, too. It is a little uncertain drawing conclusions from just one chain/sprocket set, but I have anyway. My impression is that the chain and rear sprocket show no adverse effect from the use of WD40, but the countersprocket probably benefits from a lube that provides a little more cushion.
For those that haven't read the whole thread, this is a '75 750F and the miles are mostly commuting in all kinds of weather.
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