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. 

The S numbers are the original War Department numbers from late 1939 onwards. Prewar military bikes had numbers without the prefix in line with the civil bikes. 
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 Year Engine number


Lex Schmidt Holland   103162/5080 1938 87906 Civvy engine but appropriate under restoration
Brian Walker England 1939 S1063 1940 S2621 Under restoration
Petra-Dubrava Museum Complex Russia 1940 S1270 1940 S1270
Marcel Jansen Holland 1940 S1339 1940 S1339 Under restoration
incognito Holland 1940 S1373 1940 S1756 no sidecar
Michael Roberts Canada 1940 S1433 / S5539 1940 S1559  
National Motorcycle Museum Birmingham England 1940 S1728/?? 1941 S5040 Restored by Roger Deadman and later David Bailey
Lex Schmidt Holland   S1732/S1732 1940 1732  
Martyn Streeter England 1940 S1948/S3021 1940 S1948 (Sidecar of 1941)
Tibo van de Zand Holland 1940 S2145 ?? none Engine only marked with C4185668
Thomas Wältermann Germany 1940 S2224 1940 S2224 Under restoration
Alexander Lorsheid Holland 1940 2239 1940 S2239  
Dorian Micallef Malta   2361/S4283   4260 Under restoration
François France 1941 S2469   AS1177 No sidecar
For sale ebay Dec 2012 Australia ?? ?? 1941 S2620  
Dave Wolfe Australia 1941 2739/?? 1941 S2777  
George Brennan Australia 1941 S2766/S4139 1941 S2766  
Dave Walters England   S??70  / S2704 ?? AS1066  
Mark Palmer England 1941 3726 or 29 1939 94016 probably civil engine
Paul .. France 1941 S3968/S3968 1941 3968 Restored by Lex Schmidt
Phillip Thompson Australia 1941 4097/2873 1941 S2837  
Michel Clements Holland 1941 S4973/2817 1941 S4973  
John Tinley  England 1941/42 4622 1941/42 S4618  
Rob Miller England   4946/4142/S4404     Sidecar chassis number 4142,  S4404 on spring mount
Mr Fenton Ireland 19?? ?? 19?? ??  
incognito Scotland 1942 S5222 1942 S5222  
Ron Pier England 1942 S5331 /S5421 1942 5331  
Raymond Dempster England 1942 5754 1942 S5754  
Enrico Barbaglia Italy ? ? ? ? ?
Guiseppi Malta ? ? ? ? ?
Yoram Binur Israel 1954   1954   Ex Egyptian army, no sidecar




  Jan Kerckhof Belgium       S1312  
  Johan Leenders Belgium       S1867  
  Arnold Hoekmeijer Holland       2137 Sometimes used in 16H frame
  For sale in a civil Big 4 in Indonesia E bay aug 21 2006 Indonesia       S3192  
  Johan Leenders Belgium       S3621  
  Thomas Wältermann Germany     1940 S4495  
  Clive Micallef Malta       4516  


  Lex Schmidt Holland 1941/42 4855