Quote Originally Posted by Jonathan View Post
You should be able to work it out more accurately by counting the teeth on the gears, so you can work out the ratio. Then count the teeth on the pulley and find out the belt pitch. Post the numbers and we can work it out, if it's not obvious.
That was actually my first thought Jonathan as I had a distant memory of doing something like that donkeys years ago when I could call myself an engineer lol.
Problem is that I didn't think of it before I put it all back together & now it's all sat inside it's little box it's almost impossible to do that so was hoping for an easier way.
If it has to come out again then so be it.