Unknown BSA Model and Year

[bourbon12]

I owned this bike about 45 years ago.  Am trying to locate the bike, if it still exists.  Do not have model or frame numbers.  I think the Model year was somewhere around 1954.  I know it was a two cylinder, had chrome fenders and tank panels and handle bars  So far, it looks to me like it may have been an A65H Hornet, but it looks like the fenders and megaphone mufflers may have been after market additions.  Would greatly appreciate any insights that anyone may have regarding identification of this bike.

[lxmlvll]

Hi,

The year is about right.
It's a plunger A7 or A10 with the bolt together engine/gearbox, made from approx. '52 to '55 I think, being replaced by the swinging arm derivative.
The A50 and A65 unit construction machines did not appear until after 1963.

Regards

A.

[L.A.B.]

Yes, plunger A7 (500cc) 0r A10 (650cc) with some modifications.

Plunger models were made from 1949 to 1957, and swinging arm versions available from 1954-on. The A50/65 models being introduced during the 1962 model year.

[bourbon12]

Thanks for the info.  I guess plunger was a reference to the rear wheel suspension that had a rigid frame and the wheel moved up and down within the frame.  

[L.A.B.]

The 'plunger' models had a basic form of suspension where the wheel is held by lugs that slide on vertical rods attached to the frame and controlled by springs either side of the lugs.  
 
This system (as you would expect) can wear rapidly if not lubricated fairly regularly, the rear wheel can then  move out of line and the handling of the motorcycle deteriorates, and there's no real damping either.  
 
Swinging arm (UK speak) or swing arm (US speak) was eventually adopted by BSA and most other manufacturers, because it was considered to be a better system.