Dear Patch11brig,
The picture of your father, - he is sitting on either a Mark4 or mark5 1950 to 1953 model, the tone of the grey paintwork suggests it was either the metallic blue of the 50 to 52 period or green of the later mark 5 models. The colours were not specific to the year of production but does give some indication.
Do you have any record or recollection of the colour?
I presume you know nothing of the detail of the bike other than the registration number, however if you send that direct to my email address I will discuss it with our Club machine registrar to see if any trace of it exists in our records. If in the sadly, unlikely, event that we can find a record and therefore determine the frame number we could identify its early life from the dispatch records.
You do not say you are familiar with the Douglas range, The mark series were introduced shortly after the second world war with the first transverse 350cc twin being called the T35 Mark1. this was superceded by the mark 3 then 4 and finally the 5. the 3 and 4 also had "sports" models. The Factory also produced small numbers of higher performance madels called the 80 plus and 90 plus, the only other post war mark type machine was a trials version with a solid rear frame.
All production post war Douglas machines were 348cc OHV transverse machines the mark series having the unique torsion bar suspension. in 1954 the models were finally replaced with the Dragonfly. Final production finished in 1957.
Dave
