WD Big 4 engine and frame numbers

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Looking at the various lists available, it seems that there are gaps in the numbers known versus the numbers expected. One way to try to fill these gaps is by making an inventory of all existing numbers. This wil inevitably be an incomplete inventory (many bikes lost, not everybody responding etc) , but it will hopefully give some insight in the numbers. 

Norton used a rather confusing system to number frames and engines from the early start. Frames and engines were numbered at manufacture but there is no link between them, nor any prefix used. Hence, all pre war military Nortons had different i.e. "non matching" engine and frame numbers.
With the start of the purely military production the frame and engine numbers were matched and given a Big 4 model specific "S" prefix starting with S1000 around November 24th 1939.

Like with WD16H engines, also engines with an AS prefixed spare engines are found.
  Norton did not make a distinction here to separate 16H and Big 4's. 

Dating the bikes based on the contract numbers is a tricky issue. Bikes made on a contract date in one year could very well have been delivered the next year. I added the most likely manufacturing year without pretending to know it exactly!

The only valid position for a Norton applied frame number is on the left hand front petrol tank frame lug casting. The engine number is found on the left top corner of the left crankcase half. Sidecar chassis number is found on top of the front lower sidecar to motorcycle fixing.  (See pictures below).


On (WD)16H´s I have found different casting numbers on head stock and saddle fixture. I'm wondering if this has happened with the BIG4's as well. If anyone has these numbers, please add them. Frame casting numbers are found at the left, aft side on the steering head, saddle casting number is found on the left-hand side below the saddle. 
Petrol tanks have individual numbers at the bottom, front forks have individual numbers at front lower cross brace (left hand side when viewed from the front).

If you want to help unravel the past, please send me your frame, engine and sidecar chassis numbers (and preferably the others as well).
If you want to have your bike on the website, send a picture.
I will only add bikes to the website after the owner has given his written consent unless it is a museum piece or publicly advertised for sale!

Note: In case a frame number is not known or  not applied by Norton, the engine number of the MC is "assumed" to be matching  and the MC added in the list accordingly.


(WD)BIG4 Motorcycles

Engines and Frames

Click to enlarge Owner / picture Country Year Frame number/ Sidecar chassis number Contract Year Engine number Contract


Lex Schmidt Holland   103162/5080 C2925 1938 87906   Civvy engine but appropriate under restoration
Brian Walker England 1939 S1063 V3565 1940 S2621 C7576 Under restoration
Petra-Dubrava Museum Complex Russia 1940 S1270 V3565 1940 S1270 V3565
Marcel Jansen Holland 1940 S1339 V3565 1940 S1339 V3565 Under restoration
Name withheld upon request Holland 1940 S1373 C5333 1940 S1756 V3849 no sidecar
Michael Roberts Canada 1940 S1433 / S5539 C5333/C13056 1940 S1559 C5333  
National Motorcycle Museum Birmingham England 1940 S1728/?? V3849 1941/42 S5040 C11297 Restored by Roger Deadman and later David Bailey
Lex Schmidt Holland 1940 S1732/S1732 V3849/V3849 1940 1732 V3849  
Martyn Streeter England 1940 S1948/S3021 V3849/C7576 1940 S1948 V3849 (Sidecar of 1941)
Tibo van de Zand Holland 1940/41 S2145 C6831 ?? none C6831 Engine only marked with C4185668
Thomas Wältermann Germany 1940/41 S2224 C6831 1940/41 S2224 C6831 Under restoration
Alexander Lorsheid Holland 1940 2239 C6831 1940 S2239 C6831  
Dorian Micallef Malta 1941 2361/S4283 C7576 1941/42 4260 C11297  
Name withheld upon request England 1941 S2451 C7576 1941 S2451 C7576  
François France 1941 S2469 C7576 ?? AS1177  ?? No sidecar
For sale ebay Dec 2012 Australia ?? ?? ?? 1941 S2620 C7576  
Dave Wolfe Australia 1941 2739/?? C7576 1941 S2777 C7576  
George Brennan Australia 1941 S2766/S4139 C7576/C11297 1941 S2766 C7576  
Dave Walters England   S??70  / S2704  ??/C7576 ?? AS1066    
Mark Palmer England 1941/42 3726 or 29 C11297 1939 94016   probably civil engine
John Moore England 1941/42 3762 C11297 S3762 C11297    
Gary Lawlor Ireland 1941/42 S3784 C11297 S3784 C11297    
Paul .. France 1941/42 S3968/S3968 C11297 1941 3968 C11297 Restored by Lex Schmidt
Phillip Thompson Australia 1941 4097/2873 C11297 1941 S2837 C7576  
Michel Clements Holland 1941 S4973/2817 C11297 1941 S4973 C11297  
John Tinley  England 1941/42 4622 C11297 1941/42 S4618 C11297  
Rob Miller England 1941/42 4946/S4404 C11297 1941 S2442 C7576  
Mr Fenton Ireland 19?? ??   19?? ??    
Name withheld upon request Scotland 1942 S5222 C11297 1942 S5222 C11297  
Name withheld upon request England 1942 S5327 C13056 1942 S5327 C13056  
Ron Pier England 1942 S5331 /S5421 C13056/C13056 1942 5331 C13056  
Raymond Dempster Northern Ireland 1942 5754 C13056 1942 S5754 C13056  
Enrico Barbaglia Italy ? ?   ? ?   ?
Guiseppi Malta ? ?   ? ?   ?
Yoram Binur Israel 1954 - - - - 1954     Ex Egyptian army, no sidecar


  Name withheld upon request England


    1939/40 S1097 V3565  
  Jan Kerckhof Belgium       1939/40 S1312 V3565  
  Johan Leenders Belgium       1940/41 S1867 V3849  
  Arnold Hoekmeijer Holland       1940/41 2137 C6831 Sometimes used in 16H frame
  For sale in a civil Big 4 in Indonesia E bay aug 21 2006 Indonesia       1941 S3192 C7576  
  Johan Leenders Belgium       1941/42 S3621 C11297  
  Thomas Wältermann Germany       1941/42 S4495 C11297  
  Clive Micallef Malta       1941/42 4516 C11297  
  Rob Miller England       1941/42 S5119 C11297  


  Lex Schmidt Holland 1941/42 4855