#SMITHS CHRONOMETRIC SPEEDOMETER SERIAL NUMBERS SERIAL#

The 1953 BSA 650cc Super Flash Rare Serial no. The Motorcycle offered: BSA Super Flash “no. In total there were 577 plunger Super Flashes produced. Production of a swing arm Super Flash started late in 1953 with only 19 units shipping between December 1953 and March 1954 before BSA revised their 650cc product line and introduced the A10 Road Rocket which started shipping at the end of April 1954. The final plunger Super Flash shipped in November 1953. The bike was in US showrooms in April that year at a price of $975. The first Super Flash was shipped to America in February 1953 and American Motorcycling magazine awarded it ‘Motor of the Month’. A 2.5-gallon Gold Star style tank and chrome mudguards and stays were fitted.

The frame also had lugs welded on for rearset footrests.

The large 10TT9 racing carburetor required the seat post of the frame to be bent backward with a “kink” to allow for clearance. Power output was 40 bhp (30 kW) and a triplex primary chain was installed. Hopwood decided to make a faster model by bolting on performance parts to the existing A10.Įngine modifications included a 357 race camshaft and an Amal TT carburetor. Works rider Fred Rist had an A10 desert racer capable of 140 mph, and Gene Thiessen set an AMA class ‘B’ record at the Bonneville salt flats of 151 mph in October 1951. They had tuned versions of the 500cc A7 for the Daytona 200 and other races.

The BSA Competition Department had experience tuning the existing models. Although a swinging arm frame and alloy head for the BSA A10 were in the planning stages they were some way off. The A10 was so closely based on the A7 that it used many of its well-proven components, and this large carry-over of parts from the A7 promised greater reliability, with minimal risk of new technical problems.Īfter a market research tour to America in 1951, Hopwood realized the need for a more powerful variant for the all-important American market. The conrods were of the split type with shell type big ends.Ī semi-unit gearbox, bolted to the rear of the engine cases, meant the duplex primary chain was adjustable via a slipper tensioner within the primary chain case. Main bearings were roller drive-side and a white metal plain bush on the timing side. The crankshaft was a bolt-up 360-degree item (both pistons went up and down at the same time). Lubrication was dry sump with oil being distributed by a mechanical pump located inside the timing cover. A dynamo was positioned in front of the cylinders, driven by a chain. A magneto was located behind the cylinders, driven by a train of gears, to provide ignition. A single camshaft behind the cylinders operated the valves via pushrods passing through a tunnel in the cast iron block.

#SMITHS CHRONOMETRIC SPEEDOMETER SERIAL NUMBERS PLUS#

It had a 70mm bore and 84mm stroke, a revised alloy rocker box and cast-iron cylinder head, plus an integral manifold for the single Amal Carburetor.

Bert Hopwood, designer of Triumph’s Speed Twin, having been enticed away to Norton for but a year and the design of their Dominator engine, was persuaded to join BSA in 1948 and set the task of creating a competitive 650 twin.Įssentially a redesign of the A7, increased to 650cc, the Hopwood-designed A10 Golden Flash was launched in 1949. They had the A7, a 500cc parallel twin, but needed a 650 to stay in the running. The largest manufacturer of motorcycles in the world had to retaliate. Triumph had rocked the BSA boat of motorcycle manufacture with the introduction of the 650cc Thunderbird in the early ‘50s.

Smiths chronometric speedometer serial numbers