Frame Nos - Post War Engine Nos. Post War
R C / 1 / 0 0 0 0 B / A F 10 A B / 1 B / 0 0 0 0
R= Rapide                          
(All post war frames)     Sequential Number               Sequential Number
        F= Four Stroke      
Blank = Series 'B'         T= Two Stroke      
C= Series 'C'                  
D= Series 'D'              
              10= 1000cc      
      5= 500cc      
Blank = 1,000cc (no / / ) Blank = All (other than)        
1= 500cc B= Black Shadow/              
1A= Grey Flash Black Prince        
  A= Aluminium    
                      M= Magnesium      
Blank = All (other than below)      
A= Metric Front Wheel Bearings      
B= Metric Rear Wheel Bearings B= Bicycle  
C= Metric Both Wheel Bearings M= Marine  
D= Ball Wheel Bearings with Circlip  
E= Ball Wheel Bearings with Lock Ring            
F= Enclosed D (i.e. Farings) F10##/ 1= Rapide F5##/ 1= Speedway Engine
TT= 1950 'TT' Grey Flash 1A= White Shadow 1C= Grey Flash (Car Eng.)
1B= Black Shadow 1X= Speedway Engine
1C= Black Lightning 2= Metor
1X= Rapide (Exprimental) 2A= Comet
2= 'D' Rap/Knight 2B= Grey Flash
2B= 'D' Shadow/Prince 2C= Grey Flash (Car Eng.)
3= Half Thousand (Car Eng)
T5##/ 3= Marine (Exp) 3A= Victor