The Triumph SD was a progression of the famous belt driven Model H, which had served the armies well during the conflict of 1914-1918.
Triumph introduced all-chain drive, and for the first time, produced their own gearbox. In order to reduce the 'snatch' produced by the power pulses of a low revving, single cylinder, side-valve engine, a strong spring was fitted to the gearbox drive shaft. Hence the name given to the new model – SD – Spring Drive.
Announced in the Motor Cycling on November 12th, 1919, the SD was the new top model in the Triumph range.
However it was introduced at a time of industrial unrest and raw material shortages and so Triumph underlined their 1920 sales catalog with, “Owing to many manufacturing difficulties, it will only be possible to produce this model in limited quantities”.
Initially priced at £110-0-0 (a hefty £18 above the Model H) the Model SD was Triumph's first machine to cost over £100, and due to the rapid inflation of the period rose in leaps and bounds to peak at £ 140-0-0 by the beginning of 1921.
On Nov 14th 1940, the Triumph factory was destroyed in the air raid on Coventry. All records were lost of models built, dates and total numbers.
4 decades later, in the early 1980's, Peter Cornelius accepted the challenge to accurately date every pre-1940 Triumph motor cycle, and spent ta further 4 decades intimately researching the details of every pre-1940 Triumph, to rediscover the 11 missing coding systems.
Recognized as a global authority on Vintage Triumph motor cycles, a Marque Specialist for the Vintage Motor Cycle Club in the UK even when he emigrated to NZ, Peter is the author of 28 books on Triumph history before 1940.
Peter Cornelius wrote 28 books in total covering the period of early Triumphs and this particular book has a unique position in being the very first book that he completed.
Although editing for republication, I (Richard Cornelius, Peter's son and now Custodian of the books) came across the following note that Peter had sent out along with a review / advertising copy.
“Enclosed is a copy of a booklet for review in the Old Bike Mart/VMCC Journal. This is planned to be the first of a series of booklets covering each of the various models which Triumph produced over the years. (Produced irregularly and randomly.) In order to avoid the costs of professional printing and thus keep the purchase price down I have resorted to local copying of my computer produced document. This first booklet will probably be the smallest in page numbers and as so few were made even fewer have survived, thus I have only done a print run of 30 copies.”
Following this initial print run, every book in the series has been in high demand, and thousands sold worldwide.
Now, for the first time, these books are available to a wider audience, due to global distribution and modern printing technology.
Are you riding or restoring one of these early Triumph motor cycle?
Researching aspects of your family history?
Interested in motorcycle history?
Maybe needing the correct historical FACTS for your book or film project, or auction item?
Then this book, being filled with accurate technical details; images and diagrams from the period; and historical information – The FACTS – is for you.
Each book within the Triumph The FACTS series, is the result of patient, dedicated and meticulous research over decades, by Peter Cornelius, and covers a single motor cycle or related models., in detail.
This series of The FACTS books has been titled due to a remark from someone whom Peter assisted with his restoration.
“Over the years many people have given me advice but you are the only one who has ever given me FACTS!”
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