The one I had on was a Troy Built stationary gear that I could adjust forward and aft. The harmonics on my Cycle One frame was terrible. Very well built product and no beans with Troy, he tried to help me every way he could. But my bike would sing a song that drove me nuts. I even Youtube it to Troy and he agreed it sounded bad. Somewhere there is a rule of thumb on how many links you can go before the chain needs additional support. I'm don't remember where I read it, but I'm a link or two over that number, and I'm OK so far.