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1938 BSA M series frame/engine info required

Hi all.
Can anyone help with identifying correct frame/engine number match for my 38 BSA M20 or M23.
Frame number is JM19 300
I have a bsa records doc stating it was a BSA M23 empire star. There is a tally no. of 4493 (what is tally no?)The engine has been changed but in 1942 the bike was registered with engine number JM23 159. I believe this was the correct and original engine to the bike but would like to know for sure.
Can anyone help please.
Marcus

email (option): Marcus@glassenbury.plus.com

Re: 1938 BSA M series frame/engine info required

Hi Marcus.
The 'JM19' frame prefix was used for 5 different models in 1938, the M19/20/21/22/23. The only way to know for sure what model the bike started life as, is from the factory records! If you have confirmation of this being a 'M23 Empire Star' from the factory ledgers, then this is what it is/was and 'JM23' would be the correct engine number prefix. The numbers that you have quoted look to be both original and correct for this bike. Nice! What engine is currently fitted? Regards, Pete

Re: 1938 BSA M series frame/engine info required

Hi Pete.
VMCC supplied a certificate I guess from factory records stating that frame number was a M23. It would make sense that the engine number 159 would be lower as like you said the JM19 frame was used for quite a few models.
It currently has a M21 engine fitted. It was first registered in 1942 and declared ex government on the old buff log book. I am not sure when the engine was changed but it has maintenance unit and broard arrow markings on it. Military style headlamp and the panel in tank is blank. It was registered to RAF Hullavington.
I just wondered if any BSA factory records would show that the M23 engine number I have and frame were together. I know I will not find the original engine so will most likely leave the M21 in it for now with a view to put a post war ohv engine in the future.
Regards. Marcus

email (option): Marcus@glassenbury.plus.com

Re: 1938 BSA M series frame/engine info required

Hi Marcus, have a good look and see if your frame number is JM19 800 rather than 300.
The BSA despatch book gives frame JM19 300 as being fitted with engine JM23 486, that bike was sent to W Duff and sons in London (15/11/37) who were the export agent which BSA used to ship bikes to Malaysia. Not sure that the occupying Japanese gave us our bikes back after grabbing Singapore.
However engine JM23 159 was fitted to frame JM19 800, which was sent to Kings, Oxford on 8/10/37.
I don't usually gamble, but I know which I'd put my money on...
Rupert.


Re: 1938 BSA M series frame/engine info required

That’s interesting. Frame is definitely JM19 300 as the 3 has a flat top to it unlike the curve of an eight. It is very clear.
The vmcc history record also says it went to Duff and sons. Where do you guys view these records?
I have had vmcc tell me in the past that a ZM21 engine was dated 1946 but I know ZM prefix was 49 onwards?? No disrespect to vmcc.
Surely the frame number would be higher than engine number as frames were produced for all models and engine model designation slower. It has been suggested that the bike was taken by the government before being registered hence first registration 1942??

email (option): Marcus@glassenbury.plus.com

Re: 1938 BSA M series frame/engine info required

Rupert
Hi Marcus, have a good look and see if your frame number is JM19 800 rather than 300.
The BSA despatch book gives frame JM19 300 as being fitted with engine JM23 486, that bike was sent to W Duff and sons in London (15/11/37) who were the export agent which BSA used to ship bikes to Malaysia. Not sure that the occupying Japanese gave us our bikes back after grabbing Singapore.
However engine JM23 159 was fitted to frame JM19 800, which was sent to Kings, Oxford on 8/10/37.
I don't usually gamble, but I know which I'd put my money on...
Rupert.


Hi Rupert. I have just re read your message. So as you say frame JM19 300 went to Duff and sons as the vmcc certificate says. Bike does not appear to have been overseas as 42 registration confirms but it seems I may not find out what happened with the bike in the late 30’s and 40’s or what went on regarding the engine numbers? Unless both bikes JM300 and JM800 ended up in government use and engines were changed in workshops??

email (option): Marcus@glassenbury.plus.com

Re: 1938 BSA M series frame/engine info required

Hi Marcus, I have no further information on which to base any conclusions so only speculation is possible.
Flat topped '3' or not, mistakes in stampings, paperwork and registrations seem to be more common than might be expected, plus the possibility of numbers being altered at any time after the bike left the factory.
To me the key fact is that the 1942 registration gives the engine number as JM23 159, which was supplied new with a frame number remarkably similar to the one you have, and the alternative bike in the 'frame' was most likely sent half way round the world.
Plenty of "yes, buts" attached to that, no way of now being sure.
Rupert.

Re: 1938 BSA M series frame/engine info required

What I find amazing is that people actually expect that a frame will have the same engine in it after 80 years.
Back when my A 10 was daily transport I had 3 engines for it
The original which went in for the annual inspection, the monster high compression mismatch of all sorts of parts which was usually in there for hooning around on plus the spare for when the hot engine went bang big time.
In the 70's & 80's Australia was awash with bike breakers chockers full of British bikes from the 20 through to the 80's.
And from what I have gleened from period UK bike publications the situation in the UK was some what similar for bikes that survived war time scrap drives .

Re: 1938 BSA M series frame/engine info required

trevor
What I find amazing is that people actually expect that a frame will have the same engine in it after 80 years.
Back when my A 10 was daily transport I had 3 engines for it
The original which went in for the annual inspection, the monster high compression mismatch of all sorts of parts which was usually in there for hooning around on plus the spare for when the hot engine went bang big time.
In the 70's & 80's Australia was awash with bike breakers chockers full of British bikes from the 20 through to the 80's.
And from what I have gleened from period UK bike publications the situation in the UK was some what similar for bikes that survived war time scrap drives .
I think the want for correct engine type and number prefixes etc is mainly for the interest of collectability and value. As I said, for my bike, I will run it with the M21 engine and later may fit a post war ohv. Nice to have a choice!! Whatever engine is in it it won’t ride much differently. It does genuinely interest me to know what engine was fitted originally, and thanks to forums like this one some info can be obtained.
I am sure a lot has happened with my bike in its 80+ years that I will never know.

email (option): Marcus@glassenbury.plus.com

Re: 1938 BSA M series frame/engine info required

Trevor,

I don't understand why you think that is amazing. I have about 30 pre war BSAs and save for 2 all have the original engine and frame combinations. Since I want to ride my bikes as well I have not always used the original engine cases as some have been damaged by the mag being loose on the platform and causing havoc on the cases like on my Y13. Since parts availability was difficult after the war these bikes were patched up as much as possible so there were some improvements (like I would do on a contemporary bike) to keep it running or make it more rideable (like a simple twist grip instead of the horrible internal twist grip set up). Even if the engine was changed over, often the owner kept the original engine. Maybe I was just lucky or maybe things are not as bad as you think.

Regards,
Leon

email (option): leonhop3_at_planet_dot_nl

Re: 1938 BSA M series frame/engine info required

Anyone out there happen to have a JM23 engine for sale or just the crank cases ?

email (option): Marcus@glassenbury.plus.com

Re: 1938 BSA M series frame/engine info required

Leon KM20.1478
Trevor,

I don't understand why you think that is amazing. I have about 30 pre war BSAs and save for 2 all have the original engine and frame combinations. Since I want to ride my bikes as well I have not always used the original engine cases as some have been damaged by the mag being loose on the platform and causing havoc on the cases like on my Y13. Since parts availability was difficult after the war these bikes were patched up as much as possible so there were some improvements (like I would do on a contemporary bike) to keep it running or make it more rideable (like a simple twist grip instead of the horrible internal twist grip set up). Even if the engine was changed over, often the owner kept the original engine. Maybe I was just lucky or maybe things are not as bad as you think.

Regards,
Leon
I suppose it is just about how people used their motorcycles.
Down here they were used as daily transport, in the USA seems to be weekend warriours.
And then there is mileage
Down here we tend do a lot of miles and if the bike is a ride to work vehicle then you fix it as fast & cheaply as possible.
Then they get passed down to the kids and often become paddock bikes so same story.
Never many friendly BSA dealers but lots of British Bike wreckers.

I have 14 pre WWII motorcycles in various state of completeness and dissrepair
None of them have engine & frames that belong together , some are the right models but none are matching years.
2 x A 10's 2 x A 7 & 6 unit singles again all mixed & matches.
In fact the only matching numbers are the WM20 , the C10L, B 50 & A65L .

It could also have a lot to do with the registeration systems used down here
Before Harleys became the most popular bikes to steal ( still are ) british bikes were tops on the light finger list.
And up until the late 80's you could pinch a bike in NSW , then swap the engine with another pinched bike and rebirth them both in Victoria or Queensland .
After the 90's you had to change the numbers but it is no hard to add another number or letter into a BSA stamping.
Because computers were used and because the police refused to accept offers from various bike clubs to sort out potential rebirthing something like WM20 777777 could be changed to AWM20 777777 or WM20P 777777 or even WM20 1777777 and all of them would pass right through the system .

Re: 1938 BSA M series frame/engine info required

Hi all again
I wonder if anyone has found records of impressed civilian bikes that went into government use?
Mine, a 1938 BSA M23 frame number JM19 300 was used at a RAF base and the registered with a buff log book in 1942. At some point it had a military M21 engine fitted. By chance I have found a low numbered JM23 engine that the late George Wander had which I bought from him.
Not sure if I will fit it yet.

email (option): Mcsutcliffe67@gmail.com

Re: 1938 BSA M series frame/engine info required

We do have lists with civilian impressed bikes in the Australian Army. But for as far as I know, there is no such list for the British Army I'm afraid...

email (option): wd.register@gmail.com

Re: 1938 BSA M series frame/engine info required

Jan
We do have lists with civilian impressed bikes in the Australian Army. But for as far as I know, there is no such list for the British Army I\'m afraid...
Thank you for reply.
I thought it maybe unlikely, with so many motorcycles taken or used with different government departments there would have been no need to record all the information at that time.

email (option): Mcsutcliffe67@gmail.com

Re: 1938 BSA M series frame/engine info required

The term "impressed" is a bit of a misnomer really, as the British Government didn't compulsorily purchase any private vehicles. There were a couple of schemes to purchase motorcycles, and those subsequently taken on to strength were given WD serials from batches allocated to what RAOC referred to as "Local Purchase" and RASC as "Impressed". Both these terms relate to how 19th Century armies obtained supplies in the course of a campaign.

Most Local Purchase / Impressed were actually factory or dealer stock,but a number of large dealers were authorised to purchase vehicles on behalf of the Ministry of Supply and private owners, aware that there wouldn't be much fuel for the duration did take up the offer.

From memory, purchases were limited to 350cc - 500cc solos. If they had a civilian registration number, this would have been retained for Home Office use, although the army would have issued a WD number.

Extensive records were kept, but they simply weren't retained once the vehicles were sold off at the end of the war. What are the registration letters on your bike ?

Re: 1938 BSA M series frame/engine info required

Rik
The term "impressed" is a bit of a misnomer really, as the British Government didn't compulsorily purchase any private vehicles. There were a couple of schemes to purchase motorcycles, and those subsequently taken on to strength were given WD serials from batches allocated to what RAOC referred to as "Local Purchase" and RASC as "Impressed". Both these terms relate to how 19th Century armies obtained supplies in the course of a campaign.

Most Local Purchase / Impressed were actually factory or dealer stock,but a number of large dealers were authorised to purchase vehicles on behalf of the Ministry of Supply and private owners, aware that there wouldn't be much fuel for the duration did take up the offer.

From memory, purchases were limited to 350cc - 500cc solos. If they had a civilian registration number, this would have been retained for Home Office use, although the army would have issued a WD number.

Extensive records were kept, but they simply weren't retained once the vehicles were sold off at the end of the war. What are the registration letters on your bike ?
Hi Rik. Thanks for that info.
There is a lot of ifs, buts and maybe’s with my BSA.
My bike was first registered in 1942, but to make it more complicated, it was registered on engine number of JM23 159 which I believe was the engine fitted in the bike. This was period correct type stamped under seat. The original frame number JM19 300 which is clear and untouched presumably could not be found as it is not in the usual WM20 location.
My bike, JM19 300 went to Duff and Sons.
I have been told according factory records that my bike had a higher than 300 engine number.
and JM19 800 had my engine number. (See other posts in this section)
I believe hand written records may have been mid read at some point.
So basically a lot of maybe maybe. Not sure I will ever know.
Bike came to me with a WD type M21 engine fitted.
it was registered to hq at a Raf base in Wiltshire 1942,
in 49 on a continuation buff log book which I have.

email (option): Mcsutcliffe67@gmail.com

Re: 1938 BSA M series frame/engine info required

Registration is
GUC 972

email (option): Mcsutcliffe67@gmail.com

Re: 1938 BSA M series frame/engine info required

GUC 972 is indeed a 1942 London series. Probably all that can be said with certainty is that at some point between 1938 and 1942, the original registration had become lost. It may be that it had been taken on by the armed services in 1939 and then released in 1942 as production of contracted types came on stream.

Of all the pre-war factory records that I've seen, BSAs are the worst. Trying to maintain accurate ledgers in pre-computer days whilst using the same series of frame numbers for engines listed in multiple ledgers was asking for trouble.

Rupert's conclusion above, that a "3" and an "8" have been misread at some time are most likely. It would be reasonable to assume that a job or 'tally' card accompanied each frame, and if that had a badly written figure "8" which the number-stamper mis-reaad as a "3" then the frame would have been incorrectly marked and effectively BSA would have despatched two machines with the frame number JM19 300 and none with JM19 800.

Is the frame number in the usual pre-war position of lower engine lug ? It's certainly odd that it has the engine number stamped on as well, but this could have been done to ensure a removed engine went back in the correct frame.

Is it the case that the old buff logbook shows matching JM23 159 numbers for both engine and frame ?

Re: 1938 BSA M series frame/engine info required

Yes, buff log book shows engine and frame as JM23 159. I am sure this was done when registered or re registered in 1942. Most likely as whoever or which ever workshop did not know where original frame number is, they also did not know what cc it was as engine is down as a 350cc which makes it even more likley to me that it was someone in a workshop without knowledge of BSA models.
Lower lug on front down tube is where my correct frame number JM19 300 is stamped.
I am going to apply for a new registration using correct frame number at some point, but am intrigued as to what went on in 1942 with the bike.
The continuation buff log book of 1949 was registered to Alan Douglas EDE, 32 Airman hq. Raf Hullavington. Chippenham Wiltshire
I expect I will not find anything more out except lots of mistakes were made at that time with details of my bike.

email (option): Mcsutcliffe67@gmail.com

Re: 1938 BSA M series frame/engine info required

Marcus, do you know if the JM19 frame register still exists ? If so, it would provide a useful double check on any information given in the engine books.

I've looked at, for instance, the KM20 frame ledger and the KM20 standard and deluxe engine books and they're not always consistent.

As an aside, here is a 1940 mention of the scheme for local purchase of civilian machine. As far as I'm aware, the threatened compulsory scheme never came.

IMG-3557-2


Re: 1938 BSA M series frame/engine info required

Rik, thanks for giving my query some thought. I assume frame register does exists as VMCC date certificate quotes frame as being assigned as a M23 with a tally number. If that is what you mean?
I suppose what this is all leading to is, do I keep all the wrongly registered buff log book, engine number stamped on frame, wm21 engine, etc as all genuine and real history, which I believe it is ! Or would it be viewed as just a story with nothing to back any of it up. I like to have bikes with interesting history.
Hence hoping to try and find out more.
If I re register bike on original factory frame number which I could, then I feel everything else that went on with the bike is lost and not relevant any more, which would be a shame.

email (option): Mcsutcliffe67@gmail.com

Re: 1938 BSA M series frame/engine info required

Marcus, the JM19 and JM 23 engine books (first column is engine number followed by frame) are at the VMCC and the JM24 frame and engine books are both there...but I don't know if the JM19 frame book is...there are gaps and missing items. The next year's KM23 shared a frame with the KM22 and that book still exists.

I had a look at these for someone, a long time ago, but BSAs are not my speciality and I probably missed a lot. I think that you can still visit the VMCC and view the microfilm copies but they no longer allow the actual ledgers to be handled. Maybe you'd see some clues that others have missed or not been able to interpretate.

If it does still exist, the JM19 frame book will list all the frames and show which type of engine was fitted, together with number.

My personal feeling is that I'd rather have a V5 that reflects the correctly-located and factory-stamped frame number. Did you say if you have a current V5 ? If not and you use the old logbook, it will be retained by DVLA anyway and if they send an inspector, there is a risk that you could end up with a 17 digit VIN stamped on the frame.

Re: 1938 BSA M series frame/engine info required

Hi Rik.
I think I will apply to DVLA for a age related reg for my M23. I have the frame info from VMCC already and can get a dating letter. The frame info states it was designated as a M23.
Like you say, it is better to be registered on correct frame number, I have a JM23 engine but it needs work. Still, a empire star is a good BSA to have although I will not restore it in anyway.

email (option): Mcsutcliffe67@gmail.com

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