I went hunting all over the big city (Calgary) looking for a 415 chain or master links. I tried a 420 size, which DID NOT fit, although it should have. I swallowed my pride and paid $36 to have a few master links shipped from BC express courier. If you do buy master links, buy a bunch to make it worth while. Not one bike shop had one big enough, and not one motorcycle shop had one small enough! I would advise anyone to buy extra chains and links. Use a derailler sprocket on the idle pulley instead of that cheap plastic piece of crud. Just mount it on a 5/16 x 1 1/2 bolt with a smooth bit at the top, and bolt on, works like a shot!