05-28-2020, 05:42 PM
Richard, the roller links stick out further than do the outer plates. The curve of the peanut across it's widest part should be .356 according to ANSI/ASME Spec B29.1. Chains should meet the above spec. If you take the radius, multiply it by two (to get .356), take the pitch diameter of the 9T sprocket, 1.097, subtract the .356 and you end up with a .741 dimension. This is the max. diameter you have left so that the chain will just touch the neck between drum and sprocket. Of course, you want to have some clearance, so a .688 diameter would be the max that I'd want to see. I had a flat washer under my clutch nut that was actually a bit bigger in diameter than the aforementioned .741 diameter, so that my chain was riding on the washer. I realized this was twisting my chain as it ran across the top sprocket, so I dug up a smaller one from ARP fasteners. I would like someone to measure the neck diameter on some 9T clutches to see how much the links can whack the neck when the chain is whipping around. I'm glad our AZ tracks are "open" enough so I can run a 10T. This means I have no clearance issues, plus I can run a needle bearing in my drum. As long as I put a dab of Moly disulfide grease on the needles once in a while, the needle runs for a very long time. I've also had folks tell me that a needle bearing running on the West Bend crank will cause problems. I've been running the same crank in my 610 for eight years, and there's no sign of wear. I run 10T needle bearing Max Torques and Rev Grips. TJ