Hi!
There is a pair of bolts that holds the lower part of the rear mudguard to the rest of the mudguard. To enable the wheel to be removed more easily
The sad fact is that one of them has made an escape to freedom. I have taken it's mate off, and have had various thread gauges around it. The thread is a little old and tired and I'm still none the wiser as to the pitch. May be some old cycle thread?
Any help would be great..
Kind regards
Colin

Hi Colin...They are 5/16" Cycle thread...Ian

email (option): ian@wright52.plus.com

Cycle thread is a 60 degree included angle, 26 TPI.

email (option): britool51@hotmail.com

Colin, this is from a BSA publication & shows the 20tpi series that you will also find used on your machine.

Thanks chaps for the info. It's very much appreciated.
I should get the old girl sorted for the summer now..