[Matt Adams]

The short answer is: there's a whole lot more you need to know about cutting speeds and feed rate. It really depends on the material the gear is made out of. If it's a hardened spur gear, you can have quite a bit of trouble cutting the material itself.

As for the lathe hitting the drilled out edges, it's a dynamic forces sort of thing since the metal will continually be engaging metal as it spins. I could honestly see this as a, "it's no big deal" or "don't you dare try to lathe that!" situation. You might be better off to just 2nd day ship out the gear(s) and lathe it down.

If you're just looking to reduce weight, it's just a matter of ounces you're looking at since you already have a fairly nice bolt patern in there... is it really worth it?

(I know, it's always worth it when you're 3 ounces over weight. It's also worth it if the hub is interfering with another component)

Anyway, hopefully you'll be able to post a little more information about the gear so that a machinst can throw out some speed and feeds for you, especially in this situation.

Matt