These early machines had a top yoke with rubber bushes to dampen the handlebars, and when did they change to the longer forks?
Obviously there is going to be a long list of little changes many of which there may not be a definitive answer on exactly when it changed, but its certainly worth the attempt.
Rob
I spoke at length with Henk about a year ago about the forks. He said:-
"The first photo that clearly doesn't have a brake rod and is a BSA with frame number WM20.25307, this BSA seems to have the front mudguard spacer fitted"
Which I think must put the change to long forks at some point in 1941.
A couple of points - I think you may need to find a side damper nut as opposed to the side damper wheel + some rubber driver's footrests terminating with circular steel discs - you may also need to mount the speedo centrally as opposed to off set but those brackets I do not think are hard to find. I am sure there are plenty of folk on here who could compile a comprehensive list.
I have an October 41 project bike which had
Short forks
Bakelite side damper knob
Brake rod
Ribbed rear mudguard
Balloon tank
8” headlight
Standardised levers
No footrests but possible to use solid or rubber as the changeover took place then
Rear frame had no footrests
Rear frame had side stand lug
Although built in 41 - the frame no sequence was from mid 1940
Early parts - some - appeared later than some of us may think
Am I right in thinking that the speedo drive would be on the left as on the later bikes but still having the rod front brake, therefore no brake cable adjuster "post" on the plate.
Mike W
In one of the posts I remember seeing the Saddle Bolts/Studs were different for the early BSAs to accommodate the Horn.
Please validate my understanding
No not all M20's had the horn located there. According to the historic facts, the horn was relocated sometime in 1942. I don't know the reason, but I have heard, that the horn couldn't be heard when the rider was wearing the long mac, whether that's true or not.