As there was great interchangeability of parts, there have been a significant number of bikes erected “in the style of” for instance, TT Replicas and Sprint Specials.
At times there has been a temptation to claim these as “original” as it elevated their value.
With the discovery that the works despatch records still existed, this has exposed quite a few imaginative claims.
However, with the correct information now known, if such spurious claims are to be given credibility, then the correct numbers must be used.
When John Underhill is asked to verify frame and engine numbers, he asks for rubbings. to be as sure as possible, you can remove paint to expose bare metal on the frame. You can then see if there is a “flat” where the original numbers have been filed off or stamped over.
John likes a rubbing to see how closely the font style and size corresponds to those known to be used by the factory.
Similar observations apply to the crankcase, although as so many have had rods through and have been replaced.
It is possible that an error in stamping has been made, but if you want a little more peace of mind, make rubbings of the respective numbers and send to John Underhill (Contact details in front cover of Yowl)
I would suggest you also send a photo of the bike, what information you have about previous owners and how it was described to you when you bought it. The importance you place on these facts is up to you.
Scotts were also very creative in re arranging conveniently available components to present “new” models