Hallo. Im from indonesia..

I have a BSA M20 motorbike with engine code WM 20 20274

but the engine is in my bsa motorcycle in the civilian version.. what year is the motor..
while I see if the motorbike uses the W series.. the motorbike should be in the series for non-civil war.. I ask for information

email (option): sultony.andrian@gmail.com

Engine no. WM20 20274 was delivered under a War Office contract, No. C6126 and was produced in June 1940. It was fitted in a frame with the same number which displayed the WD serial number C4172488. This is the closest that I have on file.



What is your frame type and number ?

I have 22793 here
Interesting exhaust silencer on that bike too
Jo’b

email (option): jonnyob1@googlemail.com

It looks like a standard silencer to me John? Ron

email (option): ronpier@talk21.com

Hi ron
An optical illusion with the rear stand It seems
Eyes tired clearly after a long road trip & ferry crossing last night
Jo’b

email (option): jonnyob1@googlemail.com

I live in Indonesia.. I am currently assembling the BSA M20 which was salvaged 15 years ago from my father. I found the engine number with the code WM20.20274 with the civilian version because the frame number is ZB.4345 with a rigid shape and fork telescope and there is a mount for a seat or pillion on the side or sidecar. This motorbike was bought by my father as a full unit. can you detect how it should be or what the frame number corresponds to the machine code.

email (option): sultony.andrian@gmail.com

I have a photo my frame and my machine number. But i dont know how to upload. Can you teach me?

email (option): sultony.andrian@gmail.com

email (option): sultony.andrian@gmail.com

email (option): sultony.andrian@gmail.com

final bca indonesia open 2017

email (option): sultony.andrian@gmail.com

Hi from UK. Z is for the 1949 model year and B is for the B series models ie B31 B33 (OHV models) Ron

email (option): ronpier@talk21.com

Thank you for the information. I can confirm that the frame I have is not original with a wm.20 engine, the frame and full body are B33. because there is a support machine at the bottom. if the b31 engine is hung between the frames. did this happen from the manufacturer or indeed after entering Indonesia the engine and frame were separated and assembled separately. I don't know the history.

email (option): sultony.andrian@gmail.com

I'm quite sure that the B31 and B33 used the same Frame. An M20 engine would not have been fitted at the factory. Ron

PS "support machine" We call that a "center stand" An M20 has a "rear stand"

email (option): ronpier@talk21.com

gday ron,wondering if you could give info on my m 20,frame no is wm20 40038 and engine is wm20 51276,cheers mate ,dave

email (option): tangle.43@bigpond.com

Dave 400938 was part of contract C7287 which was for 17,000 bikes (Dec40-Aug41) Yours is the 15,038 so quite near the end. I calculate the tank census number to be C4356630.

Your engine is from a slightly later contract for 9,000 bikes C9310.

Here is an earlier bike from that "pre Pannier bags" contract.

Ron

email (option): ronpier@talk21.com

ron,thanks very much for the info,great help,cheers,dave

email (option): tangle.43@bigpond.com

Hey ron. Where is call rear stand?

email (option): sultony.andrian@gmail.com

Rear Stand. See arrow in photo.

What would she sound like with that straight pipe?