sticking my nose in here: I don't quite get the chain noise complaint. I only have gas bikes at this point, but I push them around all the time engine off, and mostly they are fairly quiet when running. I hear a slight noise, but not much, certainly not enough to be disagreeable. Its true that car makers often use a belt instead of a chain for cam drives in order to make the engine quieter, but those chains are moving a lot faster than a drive chain. Maybe I am just used to it?
Countershaft sprocket size: the rule of thumb at the race track is 13 teeth or bigger. 12 tooth causes too much chain wear as the diameter is too small. much smaller chains may have a correspondingly smaller rule, I don't know, I've never touched anything smaller than a #428, excepting bicycles. Flat trackers use a big wheel sprocket, and hill climbers. Chain grades: by all means get a sealed O ring chain from a good manufacturer- it will be much better and longer-lasting than some machinery chain. A #520 or #530 is very strong - made for 150 hp- so smaller is probably advisable. I have had good luck with emailing the Tsubaki or other chain reps for technical info. They know their stuff. I have a thing about master links, so I usually cut my own chain to length and then get the shop to put in the rivet. On the street a dab of silicone seal ( gorilla snot) on the master link is plenty good enough, most people don't even do that. And that way you don't have to go to the shop. oh yeah, if your sprockets aren't aligned, goodbye chain and sprockets! ( just lay a straight edge on them ) anyways thats what I do YMMV cheers J
