1953 EMC-Excelsior 492cc Special
Registration no. YMK 525
Frame no. S1528
Engine no. 3B990
Less than 12 months after his BSA-Anzani special (Lot 345) had featured in Motor Cycle, David Blanchard was back in the magazine again when his unique EMC-Excelsior triple featured on the front cover of the 4th July 1963 edition. Amazingly, David had only commenced constructing his latest special in 1962 so to have it roadworthy by the following summer was an outstanding achievement. This unique hybrid consists of a 1953 EMC frame and a 492cc Excelsior three-cylinder engine, bought new from the factory, of the same type supplied to Berkeley for their three-wheeled SE492 sports car (purchase receipt on file). Excelsior's triple produced a claimed 30bhp and boasted the added convenience of a SIBA electric starter, though having to find space for the largish 12-volt battery necessitated fabricating a special under-seat mounting.
Early on a major problem was encountered when the engine was offered up to the frame: the rear chain line was miles out, a problem all too frequently encountered by builders of specials. Aligning the gearbox and rear wheel sprocket would have meant moving the engine way over to the right, unbalancing the machine, so David opted to interpose a second (Burman) gearbox behind the engine to achieve the necessary chain alignment. The front gearbox remains in 1st gear and changes are made using the Burman four-speeder. As the Excelsior engine/gearbox unit was intended for car use, a reverse gear is incorporated, which is engaged by moving a hand lever and selecting 1st in the Burman 'box. The EMC cycle parts were left relatively standard, except for the substitution of a BSA 7" front brake for the original.
'A brief run on the red and two-tone grey "EMC" proved the point that a two-stroke multi is out on its own for smoothness,' declared Motor Cycle's tester, David Dixon. 'But what was a big surprise was the astonishing flexibility; useful top-gear acceleration on a ratio of 5 to 1 was on tap from only 10mph, and it was possible to jog-trot alongside at a mere 8mph in top gear! Hardly any coaxing was required to pull away in third.' What a pity Excelsior never developed a version of this exceptional engine specifically for motorcycles!
Dixon concluded: 'A craftsman to his fingertips, David Blanchard knows what he wants in motor cycles and his latest creation is a remarkable tribute to his skill and taste,' sentiments with which we can only concur.
The machine is presented in generally good condition, though its mechanical condition is not known; thus careful re-commissioning and the customary safety checks are advised before returning it to the road. 'YMK 252' comes with a most substantial file of history including period press photographs; correspondence from the Excelsior Motor Co Ltd, Motor Cycle magazine and others; construction diagrams and notes; assorted press cuttings and technical literature; Excelsior 'Running and Maintenance Instructions' books (x2); SIBA Dynastart manuals (x2); various motorcycle magazines; sundry invoices; its original logbook: a quantity of expired MoTs (most recent 1972); three old tax discs; and an old-style Swansea V5. A box of assorted engine spares and a set of carburettors is included in the