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c.1933 New Imperial 350cc Grand Prix Project
Frame no. 93/22582/TT
Engine no. 29399

• Ultra-rare six-stud works racing engine
• Grand Prix frame
• Known history
• Offered for restoration

After an abortive attempt in 1901, New Imperial commenced series production of motorcycles in 1910. By 1913 the fledgling firm was contesting the Isle of Man TT races, entering a trio of 500s in the Senior event, none of which finished. This disappointment and the intervention of WWI delayed New Imperial's next appearance until 1921, but what an historic return it would be. At that time there was no separate Lightweight TT race (the 250s would not have their own separate Lightweight TT race until 1922); instead a trophy was awarded for 250cc machines entered in the Junior (350cc) event, the first such award having been made in 1920 when Levis secured a resounding victory, taking the first three places. New Imperial entered five JAP-engined 250s in the 1921 Junior and although four retired, Douglas Prentice's went on to win the class at an average speed of 44.82mph, Bert Kershaw's having set the fastest lap.

New recruit Bert Le Vack came close to victory in the Junior event the following year and finished second in the Lightweight race in 1923, and then the Twemlow brothers' 1924 Junior/Lightweight TT double - Ken winning the former, Eddie the latter - plus Eddie's repeated Lightweight victory in 1925, confirmed New Imperial as one of the dominant forces in 250 racing in the Vintage years. New Imperial had switched from JAP to engines of its own manufacture by the decade's end, and although the 1930s brought fewer success in the Isle of Man TT, Bob Foster's 1936 Lightweight TT win was notable as the last achieved by a British-made '250' until Eddie Laycock's 1987 Junior TT victory riding an EMC.

This machine consists a 1933 works racing engine in a Grand Prix frame. The New Imperial engine build book (copy extract on file) shows that five of these 350cc engines were made and signed off on 15th May 1933 in readiness for the 1933 Junior TT. Engine number '29399' is the last engine in this block of five. The introduction of this six-stud design was reported by the period magazines (see The Motor Cycle 11th May 1933 and Motor Cycling 10th May 1933). The design with six cylinder-holding studs was never used elsewhere by New Imperial, either for racing or touring. These engines were used in the 1933 and 1934 Junior TT. Two of the 250cc engines were produced at the same time and were once thought to be six-stud, but at least one of these is now known to be a four-stud engine. After the 1934 TT, New Imperial decided not to contest the Junior Class any more, making these engines surplus to requirements. These six-stud racing engines are well-known in New Imperial circles but are not, as far as is known, represented in any motorcycle museum. Copies of the factory engine data sheets are included in the sale together with a selection of period photographs.

This machine has been authenticated by Charles Lipscombe, Club Historian of the New Imperial Owners Association, VMCC Marque Specialist, and author of 'New Imperial Motorcycles' (published 2006). The photograph on page 299 of Charles' book 'New Imperial Motorcycles' is believed to be of this machine, being ridden at Great Marley Hill Climb in 1933 by works rider George Holdsworth.

The frame is the highly sought-after Grand Prix type, which is the same as the works racing frame except for some gearbox mounting lugs (Albion gearbox for the Grand Prix, Sturmey Archer for the works bikes). One other example of a six-stud engine in a Grand Prix frame is known to exist, and it is likely that New Imperial sold the engines in such a frame and kept the works frames for further factory use. The frame number is correct for 1933 and early 1934.

This machine was imported into Australia in 1934, probably by Frank Pratt, a racer and motorcycle agent from Geelong, Victoria. It was raced at the Centenary Junior TT in November 1934 by Pratt's friend Ron Walter, who finished in 3rd place. It raced in Australia from that date until 1939 in the ownership of Bob Elsbury, and was sold in 1942 to Leo Andrews and used as a road bike until 1946. The New Imp was then sold to one Frank Stevens, but disappeared until it re-emerged in the hands of a collector, Charlie Wran, who realised what it was and sold it to another collector, Ken Groves, in 1974. The current vendor purchased this machine from Ken Groves' estate in 1996. The Australian press at the time referred to it as 'Dodson's Bike' (referring to New Imperial works rider, Charlie Dodson) and Dodson is pictured on one of these machines in a photograph in the Keig collection.

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