Hi folks,
I recently picked up a 1937 HM19 frame, I'm hoping to find out as much as possible about the frame and what engine it used to have, would it have been military, was it hand gear change etc.
The frame number is HM19 4237. Can anyone help please.

Many thanks.
Regards Nathan

email (option): nljb345@hotmail.com

If it's a civvy bike it will have hand change...A military bike would have foot change...These early M20s are pretty hard to find parts for...The engine, in particular, shares very few parts with the later post '38 bikes and there are many other differences across the rest of the machine...Ian

email (option): ian@wright52.plus.com

Looking at my 1937 catalouge,the same frame was used for 350cc delux,(M19) the 500cc & 600cc models .

email (option): fuzzyempire@hotmail.com

All I have is the frame and gearbox, how can I tell if it was hand gear change or not? It’s a four speed box.
Can I fit a wartime M20 engine? Is there any difference in the mounting bolt locations? I’m not too worried about keeping all the parts to 1937.
Thanks

email (option): nljb345@hotmail.com

The post 38 engine is wider because of the extra main bearing on the timing side and the cooling air gap behind the tappet chest, so the lower right frame rail is different. But I have seen it done by crudely spacing the frame rail out from the down tube. Ron

email (option): ronpier@talk21.com

If you examine the gearbox in the picture above and compare that to any picture of a later M20 the difference between the two boxes is obvious....Ian

email (option): ian@wright52.plus.com

Like it is already mentioned, a 1937 frame is different from a wartime frame. Post '38 engine's will not fit directly to the frame. The type of oiltank fitted is also different, it is not possible to fit a wartime oiltank because the mountings for the oiltank are different.

There were only 3 M20's delivered to the War Office in 1937, 2 of them went to the MWEE for testing and the 3rd 1 went to an active service unit. I will post a photo of 1 of the 2 M20's delivered to the MWEE later. I have some parts to build this bike but I am missing the frame. I would be interested in your frame.

Regards,
Bastiaan

email (option): wdmotorcycles@gmail.com

Hello,

Here is the frame of a 1938 M21. Not sure how original this is but got this a while ago. Hope this helps

Regards
Pratap Henry

email (option): prataphenry@gmail.com

email (option): wdmotorcycles@gmail.com

Hi I have a "real" 1937 M20 frame # HM 19 4135 It had been in storage since 1948, It was never modified but repainted. As had been stated above, later mid- year 1938 engines can not go into earlier frame but you can put post mid 38 chainstay to early frame front and use war type engine Trans is hand shift and trans outer case is for hand change and different than foot shift. If you need photos you may email me

email (option): millcrocfarm@gmail.com