Quote Originally Posted by D-man View Post
23 teeth and 32mm dia mate
1.25MOD is 32.69mm OD.
24DP is 1.09" (27.68mm), and 20DP is 1.308" (33.22mm), and 22DP does not appear to be a common size.

So assuming 1.25MOD and me reading the correct number from the chart, gives a pitch of 3.926mm per tooth, or 90.289mm for one rotation of the gear.

Or to assume 20DP, it would be 91.7194mm per rotation.

Are you sure it's a 23 tooth gear?
As even working backwards from 96.16mm, it doesn't fall on any common tooth size.
That's assuming I'm not making a complete hash of the calculations.

Off course, easier option would be just to measure the distance over as many teeth as possible and calculate the tooth pitch that way.