So I've totally mangled 2 rear tires, right at startup. I'll be pedaling the bike, get a decent speed going, drop the clutch, it puts for a few, then the tire pretty much collapses. I'm pretty sure whats happening is that the chain is falling off, getting caught in the spokes, and that locks the tire up and trashes it. I can only assume I'm not setting up the chain tensioner right. Does anybody on here not use it? If so how successful have you been? It seems like no matter what I do, the chain will inevitable fall off. Is there a problem with the sprocket? I'm just running out of ideas and out of motivation for this project. I don't get how people get these fired up in 4 hours =(.