A rear sprocket to fit my Yamaha rear wheel that takes #35 chain isn’t really a thing, so I modified a go-kart sprocket to fit. I had a heck of a time getting it set up on the lathe properly, in large part because the cheap sprocket was about 40 thou out of true with itself. Evidently, the outer diameter of the blank is cut separately before the teeth are stamped, so they were all different heights. The center diameter and the spoke holes were also not concentric. I had to file down the inside of three spoke holes until I got it chucked up accurately. I then cut out the center so that it’s a nice, tight fit on the wheel flange.
Then I had to drill bolt holes. Since there are four bolts on the wheel and six spokes on the sprocket, two of the bolts ended up in slots, rather than complete holes. It’s not as strong, but plenty strong enough for 5 HP and 35 MPH.
35 chain is pretty wimpy, but I bought 10 feet of RLV “Gold-on-Gold” chain, which the kart racers say is significantly higher quality and stronger than the cheap no-name chain.
