Rupert. Thank you for the production numbers for 1937/38. I have been looking for this information for some time. Most information I can find relates to WD years (understandable on this forum) and very little information is published about the parents of the WD models.
Lionel
Hi Lionel, happy to help where possible. I've done a more exact count if it might help:
HM20 (HM19 frame) 1253 produced.
JM20 (JM19 frame) 747 produced.
Anecdote - Val Page gets the bulk of the credit for these BSA engines introduced for the 1937 season, but the whole story of how these engines (and the whole bike) went from drawing board into production was very much a team effort. BSA's in-house team of design engineers (under direction from Val Page before he moved on) had the job of knocking the designs into shape for production.
At that time the top in-house design engineer - working directly under Val Page - at BSA was Herbert Perkins. I knew Herbert Perkins grandson (until he passed-on last year) who related a story passed down by his mum who was present at the following -
The AA bought a large number of the 1938 M20's for their patrolmen. Herbert Perkins out in his car with his family some time before WW2 came upon an AA patrolman with broken down M20 at the side of the road. He stopped and offered assistance to the patrolman and quickly got the bike up and running.
The amazed patrolman was more than curious; "What did you do? How did you know what to do?"
Reply from HP; "It's my engine".
Patrolman: "Who are you?" to HP as he walked away,
HP's shouted reply; "Perkins, BSA!"
Val Page is foremost of many brilliantly gifted engineers who worked in the British bike industry, a small number of whom tend(ed) to get all the headline publicity. Under those headlines was an awful lot of small print which is now largely lost.
