G'day Speedy,
I had a quick look at a spare motor but the top crank thread was half damaged .
The lower crank nut thread looked like it was 5/8 UNF that's 18 threads per inch.
The top thread was 1/2 inch ,the thread gauge would not go on because of the damaged thread but
looked like it was 12 threads per inch so if correct I think that's 1/2 inch British standard Whitworth.
If it's 1/2 inch 13 TPI that would be 1/2 inch UNC
Cheers
Max.
