Help with chain alignment

[biknut]

Keep in mind guys that the center hole doesn't have to be perfect. It's the outer diameter, the sprocket teeth that must be concentric to the hub. That center hole could be square and still work. There's no need to shoot for precision when enlarging it.

Tom

That's a good point Tom. I think the last one I was grinding on ended up kind of square lol.

 

[crassius]

I usually go out about 1/16 with a half-round file - takes a 1/2 hour or so by hand, but I'm old & not doing much else that I need to hurry on.