First of all i would like to thank ric who gave me a lot of info on this bike. He also suggested that i start a thread and see if any one knows any more.
I have started to build this m20 wm20 40486 engine and frame no. When i bought it, sadly had been dismantled 30 years before and all that remained was the frame and engine.Added to parts i already had i figured i would rebuild it back to life. So for the past couple of years ive slowly been collecting parts and am at the stage of mocking it up to see what else i need.
The bike is now 85% there just with small parts needed of which i have found drawings of most of them on this web site (which is excellent).
I was hoping someone might know some info on build date, contract no. cenisis no. where it served etc.
Other than my interest there were, as you guys know, detail changes< ie head light size etc that i would like to make correct but first i need the info.
Ric was right in his reply to me, i am in newcastle australia and that is where i found the bike.Ric thought maybe the bike served in the middle east and came back here when the australian troops came home to fight the japanese.Any thoughts or other ideas. It sounds right because when the bike was build in 1941, australia was in no immediate threat and the vehicles were needed elsewhere. Any info greatly appricated Brad

email (option): bcmotorcycles@bigpond.com

Hi Brad
according to the bible "British Forces Motorcycles 1925 - 1945"your machine was part of an order for 17,000 units supplied as order C7287,they were supplied to Chilwell at a rate of 2000 per month from May 1940 - August 1941.
Frame numbers ran from WM20-25001 - 42000 , Census numbers C4341593 - 4358592.
Assuming frames were supplied in sequential order as was usual you can calculate the correct census number
cheers george

email (option): g.gilbert946@btinternet.com

its strange that a bike from early in the war has still got the same frame/engine numbers

email (option): roger.beck@node6.com

I suggested to Brad that he might be able to find some clues to the service history in the Australian War Memorial archives in Canberra based on the original War Office census number but I don't know how the records are arranged.

In terms of engine and frame remaining together, I don't think that the REME rebuild system would have applied in all far-flung places and where only a few machines were present, they'd probably have been worked on one at a time in a general workshop.

Even in the UK, some early bikes slipped through. They were often the first sold and so were less often in the workshops than later bikes which served for another fifteen or twenty years and were used as occupational therapy for bored National Servicemen.

Hi Brad. I can't help you, but Jeff Gordon from Brissie might. Brad, do you have the AVN for the bike? Jeff own's an M20 but he does a registy for Austalian Jeep trailers from WW2 and has access to records at the AWM in Canberra. I will try and get you his email address later today if that is OK? Hope that this may help? Regards, Dave

email (option): jeepfinger@blueyonder.co.uk

Hi Dave. I dont know what a avn is so i guess thats a no on the avn.But any contacts or info is appreciated and jeffs email would be fantastic
A couple of other things i have thought of is on the plain steel tappet cover there is no workshop plate to point to the fact that it has had some army service work done. The plate is what appears to be original or at least old but seems to of had a chrome or plating at some stage. The lower head stock has been done in a similar fashion. This seems odd any thoughts. Brad

Brad,
Have emailed you with Jeff's email address. The AVN is the Australian Army Number that was issued to the vehicle. Jeff and Ian Fawbert run a registy for Australian trailers and may be able to help you. Regards and all the best. Dave

email (option): jeepfinger@blueyonder.co.uk

Thanks for all you guys that were able to help.
Dave jeff has had no luck and I had no luck at the AWM.
So it seems that it came here after the war! It seem odd that someone would have spent the money to bring it here when there was heaps of army surplus here already, but according to the AWM it wasnt bought here by the army Any thoughts Brad

email (option): bcmotorcycles@bigpond.com

Thanks to this thread I have learnt something that may help me with the history of my WM20.
A search at the AWM website found a page explaining what is required to find an AVN and made useful reading for me.
Might be of use to other people in Australia

Here is the link
http://www.awm.gov.au/blog/2008/09/19/love-that-body-whats-the-arn/

Brad - just sent you a couple of photos from that contract that are Australian Army that might be of help.

email (option): rays54@hotmail.com

Thanks Ray for your informed help and the time it takes to look through photos for me Brad

email (option): bcmotorcycles@bigpond.com

Hi Brad,
Sorry just seen your post, been away. Bad news from Jeff then but it looks like others her might have given you some leads. All the best in your hunt.
Regards,
Dave

email (option): jeepfinger@blueyonder.co.uk