We have discussed the acceptance markings on British contract bikes and the mysterious B or BB stamps on WD engines before... But here's another one, and I think I may have found out where it comes from... I'm talking about a broad arrow without a letter M and without an inspector's number.
Here's a picture of a 1942 WD/C engine that has been discovered in Australia. There is no duplicated frame number and no contract number on this engine, which makes it a spare engine. But the Royal Enfield spare engines usually have an acceptance marking, in 1942 this should have been ^M211. This engine has no such marking. But there is a broad arrow, without a letter M and without a number:
I remembered having seen similar stamps on BSA engines, and a quick search on my computer revealed these three examples (M20.49952, M20.54713 and M20.57460):
Numbers 49952 and 57460 both appear in Henk's website list, both engines are located in Australia. And although I do not know if 54713 also comes from Australia, I have a strong suspicion that this marking is an Australian Army marking. Hence my question to the forum members in general, and those who are in Australia in particular: do we have more examples of this stamp, and can my theory be confirmed?
Stay safe!
Cheers,
Jan
email (option): wd.register@gmail.com
I don't know if this helps or hinders, but way back when I was a forester in Australia, we each were issued with a hammer. it had a crow's foot on one side and a unique number inside an outline of a crown on the other. (My number was C6H). The number/crown was a recording and release mark denoting the log had been inspected, measured and recorded for sale (and by who) and the crow's foot denoted "property of the crown" which was used to mark either forestry owned equipment or siezed logs being illegally transported for eg. If someone was in possession of an item or log stamped with a crow's foot, it was clear it had been stolen. So maybe its a check mark denoting it had been counted rather than an inspection mark. I see they all appear on much the same spot on the case as if someone walked along a row of bikes striking them as they were checked off a list. This way a bike could not be counted twice (or more commonly, nicked) or remain unrecorded.
email (option): cas.vanderwoude@gmail.com
John Parker in Australia has this small BA spanner with a similar looking broad arrow. Normally AF would mean "Across Flats" But in this case, I presume it's "Australian Forces"..... Ron
email (option): ronpier@talk21.com
Bob has sent me some pictures today (thank you very much Bob!).
Engine WM2041037 has a broad arrow mark.
Engine WM2078362 has a broad arrow over a letter M over 397.
The broad arrow over M over 397 is a British Army “acceptance marking”. See more about these markings in this thread. The interesting thing is that I have never seen this number on a BSA yet. I keep a list of these acceptance markings on the M20, see attached print screen.
On the other engine there is a broad arrow with a corner of a serifed letter M! It looks as if this was also an acceptance marking, but the punch didn’t hit the engine completely… The broad arrows on the Australian engines that I found look slightly different though. Which means that the search for Australian broad arrows goes on! 
Cheers, and stay safe!
Jan
email (option): wd.register@gmail.com
I've just received Tom's pictures (thanks Tom!). The broad arrow is clear to see, but unlike all the previous pictures, this one is stamped on the frame!
It would be interesting to see more examples, on engines or on frames!
Jan
email (option): wd.register@gmail.com
This is what my M20 has Jan. Any idea of the significance of the arrow in the circle on the timing side? Ron
email (option): ronpier@talk21.com
Thanks for these Ron!
In the first picture (drive side) there's another B stamp, as discussed in this thread.
In the same picture, under the WM20 Number, there appears to be a round stamp with "A9" at the bottom (but the stamp seems to be upside down). Never seen anything like this before, but it looks as if BSA used several similar stamps: V213, V227, BSA F5. See pictures below:
The picture above also has a ^51 stamp, as in Ron's second picture. Again not unusual on BSAs:
Ron's third photo (the one you were asking about Ron) appears to have a combination of the BSA F5 stamp and the ^51 stamp... In my opinion these are all BSA factory "quality control" stamps, not military stamps, as I haven't seen these stamps on other makes yet...
Please keep them coming!
Jan
email (option): wd.register@gmail.com
These Bs are indeed intriguing me Ron!
I've just had an email from Bob, who's living in Australia. Bob has visited the National Motor Museum at Birdwood in Australia and checked their BSA for me (thanks Bob!). And yes, bingo! Another one with the broad arrow as described in my first post! The engine & frame number is WM20.46289, I'm sure Rob will be able to confirm that this one is also in the AWM ledgers.
Thanks again Bob!
email (option): wd.register@gmail.com