Tässä lainaus yhdeltä brittisivustolta:
"Pre WW II motorcycles were both taxed & had insurance rates determined by their horse power.
Cars were also the same AFAIK which is why they called things 4.95 Hp
The letters designate the bore & stroke ( so you can calculate the Hp )
So a 2.75Hp 350cc "L" model has a 72 mm bore & 85.5 mm stroke.
The Standard was SV
The De Luxe was OHV
The model "S" was a 500 or 3.5 Hp with 90 mm bore & 98 mm Stroke.
in 1924 it was available as side valve only.
By 1928 the S was available as a SV vertical , OHV vertical & OHV sloper.
In 1929 they added the SV sloper & Sports tuning so there were 5 model "S's" for that year.
Now to really muddy the waters BSA added another number if there were more than 1 model in a particular engine size
So for 1924 the range was
B 24 ( round tank )
L 24-1 ( SV )
L 24-2 ( OHV DeLuxe )
S 24 ( SV )
H 24-1 ( SV 560cc )
H 24-2L (L meaning light frame & gear box )
E 24-1 ( SV twin )
E 24-2 ( SV DeLuxe )
G 24 (1000cc SV DeLuxe)
G 24-C ( Colonial )
In 29 or 30 they changed again simply adding a consecutive number from 1 to whatever from top to bottom and dropped the -1 & -2 etc for variants of a single model, So if there were 27 bikes in the catalogue the B was B30-1 and the Colonial G would be G30-27"
t. Markku
