Aha, an extractor of entirely a different variety.

The topic of WW1 dispatch riders is a huge, but you came to the right place for info about Douglases. There is a photo guide organized by year that will give you examples of 1913 (as well as other 1912-15 models)

https://www.douglasmotorcycles.net/index.php?board=50.0

There were five models available for 1913, the models N, O, P, R, and S, The model S was the ladies model and we will assume your grandfather did not ride into the war on one of those. Otherwise there probably would have been a lot of stories handed down about that side of the family! Likewise the model N was a single speed with pedal gear, and the last year the single speed was offered at that. So unlikely one of those.

The model O was the basic 2-speed model, no clutch and fitted with foot board for 48 pounds. The model P was called the light touring and got you foot pegs and the choice of dropped or raised handlebars. Same price. The model R had a clutch and kickstart pedal, as well as valanced mudguards. That set you back 52 pounds. Unfortunately all the serial numbers (frame or engine) were sequential so no way to tell which model just from that. I was not until later on in the twenties they started using prefix letter codes on engines, frames, and transmissions to identify various models.

Quite a lot of archived military service records in the UK, so that might be another line of attack for your research.

-Doug

The LDMCC sold these at one time and there ought to be some floating about, in the UK at least.

It is a 1.445 x 26tpi thread.

Here is a post on the dimensions to machine the extractor.
https://www.douglasmotorcycles.net/index.php?msg=6560

It is for the EW, but the A31 uses the same thread size.

-Doug

Without having seen one, its a bigger version of this ?
Or possibly a 3 jawed one.

https://img.kwcdn.com/product/fancy/eaf029a1-8754-4191-a2eb-529849c79ae3.jpg

Its the centre bit that a whack shocks the flywheel loose thats the important bit...

Dispatch riders in WW1 is a vast subject. !
Millions of words writ about them, and photos aplenty.
Google - and a vast world will open up.

Photo selected at random.



I'm sure more will be said here on this, a popular area for many.
Thanks for adding your relatives to this treasure trove.....

Can anyone tell me please the dimensions of a flywheel clutch removal tool for my A31 engine?
Specifically, what is the thread and diameter of the tool needed on the flywheel?
I can attempt to then make a tool, but if anyone has such a tool they can lend me or sell to me....

I was doing some family history about my Grandfather Sam Beacham and his brother Sid who joined up in 1914.  Sid owned a Douglas motorbike and when he joined up took it with him to France. He was made a Corporal, 69034, Royal Engineers.
Sidney was promoted early on as he applied for Motor-Cycle service, having bought a Motor-Cycle in 1913. It was a Douglas Brothers 2 Speed twin cylinder engine, no 10550, 1913 model. 2 3/4 horsepower. License number ax848. He purchased it in November 1913 for the sum of £53, 11 shillings. They would only let him take his bike to France providing he had spare parts for it as welI! I would love to know more about dispatch riders in WW1 and about his bike.  Are there many still around and is there a museum where they have same model?

Thanks again Ian, The buttons which came with my jigsaw of a 'Z' only have spigots on one side which I have been positioning downwards into the corresponding holes and recesses in the crankcase top surface. This then leads to the flat surfaces of the buttons abutting the bottom of the Magneto, which has no corresponding holes, and providing no resistance to sideways movement. It looks like I will need to get some double spigot buttons made and at the same time have the base of my magneto drilled to accept them, this should lead to the long strap clamp I made working as it only needs to provide a vertical force to restrain the pair.

Chris

I have a Douglas engine that needs a new home. I believe it to be an industrial engine but unsure of where or what it came out of. 

Open to offers

Rob

I have a detachable head that I don't need. I am unsure of what model it comes from.

Open to offers

Rob