The Pre-1941 Triumph Motor Cycle Pages

From Peter Cornelius - Triumph Specialist for the VMCC - of Britain.

Answers to a few of the most frequently asked questions.

Select or scroll down for the topics below -

Q. Why was there no direct Engine to Frame number relationship?
Do the numbers raise together? If you had a chassis that was 1000 greater than mine should the engine also be 1000 greater?
Is there a direct correlation?

No way! (In post war years under Triumph Engineering Ltd. engine and frame had matching numbers, but not earlier.) Frames, engines and gearboxes (and other items) were made in different parts of the Works. In the case of engines and gearboxes these went through the machine shops (workshops) and then to separate shops for assembly. Gearboxes and frames were number stamped. Engines and gearboxes were transferred to the central stores, where doubtless they were stacked on shelves. The frames were sent to the enamelling shops for coslettising treatment and enamelling, prior to baking. Following that they were also transferred to the central stores. Most probably the transfer of parts was done by young apprentice lads with barrows. The frames would not have been transferred strictly piled in numeric order, nor handled and treated as such in the enamelling shops. Certainly the storeman would not sort and hang the frames on racks in a numeric sequence. (Business is about making money as efficiently as possible, not playing numbers games.)
When the lad with the barrow turned up at the stores for parts for the assembly of a number of complete machines in the Assembly Shop, the storeman would take the closest to hand; so it was often a case of 'last in, first out'. He wouldn't have had the time or inclination to move all the frames along the racks, or gearboxes and engines along the shelves. On final assembly the engine was number stamped, followed by a code indicating which month the machine was assembled. This would probably have been done by the Assembly Shop Foreman and recorded in a 'long gone' book. So only engine numbers have any significant numerical sequence. There is generally a 'period relationship' between engine frame and gearboxes, but occassionally, at the end of a model production, there maybe extremes. An early frame or gearbox could have stayed way down the far end of stores as other items came and went, only to finally be retrieved as stocks were running low for these last machines. Its impossible to say when a frame was actually welded, coslettised, enamelled and put into stores.

Another point is that frames were often shared among different models. While the engine number series were different for each model, shared frames carried the one number series. The only way that engine and frame numbers could have a direct correlation would be for frames to be stamped at assembly time, along with the engines. The frame stamping would then have broken through the corrosion treatment levels.
Owners today should be happy that the frame treatment has enabled so many frames to have survived in good condition, without being so concerned about whether the frame was welded and stamped a few days ahead or behind the assembly of the engine!

Q. What Transfers go on the Headstock, and whereabouts?

The transfers for the headstock are (1) a Crest transfer as on the tank. This is mounted approximately central, while above it goes (2) a 'Gold Trumpet', just below the frame number.


Q. Why do I often say that a tank is incorrectly lined?

The Model H and most Models SD and R had fuel tanks with a sharp 'cut-of' at the rear. The outer red lining correspondingly followed suit.
When the later, 1927 onward, tanks were introduced with the rear of the tank terminating at a 'point', it would appear that while the central panels followed to a point the outer red line still terminated with a 'cut-off'. This can be seen on all sales and period pictures as well as as on original surviving tanks. Why is it then that those who line tanks in restoration apply what they THINK they see, rather than copying an original picture?


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