Campy crank extractor threads are M22 x 1. Make sure you get a "bottoming tap". This will cut threads to the bottom of the tap. However it has no pilot threads, so make sure the tap is going in straight. Another alternative would be using a Bicycle Research Crank Arm Chaser. It has a pilot shaft that treads into the bb spindle, so the chaser starts out straight. It cleans up threads, but does not cut new ones. Any shop can order it for you, and it will be half the price of a tap.
Marc Boral
David Goerndt wrote:
> I have a Campy crank arm (left) that the dust cover doesn't screw in until
> flush, it's about one thread short of flush. I checked the threads on the
> arm and they weren't cut deep enough. What size tap would be required to cut
> the threads a little deeper?
>
> David Goerndt