Scott Two-speed
This 450cc Scott was very advanced when it was produced in 1910, with features including a kickstart, two-speed gearbox, and chain final drive. The cylindrical fuel tank beneath the seat was a distinctive feature of the Yorkshire firm’s bikes for many years. Telescopic fork front suspension of this type was produced from 1908 to 1930.
The bikes built by Alfred Angas Scott and his Yorkshire-based firm were some of the most innovative and brilliantly engineered of motorcycling’s early years - and also among the fastest. Scott’s two-stoke parallel twins looked, sounded and performed like nothing else on two wheels. They proved their speed on numerous occasions, not least when winning the Isle of Man Senior TT in both 1912 and 1913.
Alfred Scott was a true one-off. One of 12 brothers, he was a visionary engineer who began experimenting with powered bicycles in 1901, and three years later produced his first air-cooled two- stroke twin. By 1908 he had found premises in Bradford and had begun production of a bike based on a 333cc version of the two-stroke motor, now with its cylinder heads cooled by water.
The parallel twin engine featured a central flywheel, set between two independent crankcases. Scott had devised a simple but efficient two-speed gearbox, and also the first kickstart ever seen on a motorbike. And this extraordinary engine had a distinctive two-stroke sound, its muted purr turning to a high-rev yowl that was very much part of the unique Scott riding experience.
Hillclimb success
Scott made a stunning competition debut in the summer of 1908, when he arrived at the year’s most prestigious hillclimb at Newnham in the English Midlands with his little 333cc twin. After starting the bike with a prod of its rear-mounted kickstart (everyone else had to run-and-bump), he used the two-stroke’s superior acceleration to win three events.
His rivals were so taken aback that they campaigned to get the two-stroke handicapped (by multiplying its capacity by 1.32) on the grounds that its additional firing impulses gave an unfair advantage. Scott used this to advantage in his advertising, and his bikes continued to win many hillclimbs. He also increased the actual capacity of the engine, raising it first to 486cc and then to 532cc in 1912, by which time the twin was capable of 50mph (80km/h).
Scott’s chassis was every bit as unusual and impressive as his engine. He designed an open duplex frame of straight, triangulated steel tubes, which used the engine as a stressed member. The twins’ legendary roadholding was thanks to the rigidity and low centre of gravity of this arrangement, plus the advantages of telescopic forks of which Scott was also a pioneer. Swept- back handlebars and a barrel-shaped fuel tank, normally painted in the factory’s characteristic purple colour with two silver bands, made the bikes even more distinctive.
The two-stroke’s profile was boosted by its terrific performance in the 1912 Isle of Man Senior TT, in which Frank Applebee led from start to finish on a twin equipped with another innovation, a rotary inlet valve. Applebee lapped at almost 50mph (80km/h) and won by more than six minutes. Further success came a year later at the TT, this time factory mechanic Tim Wood taking the victory after Applebee had gone out of the race while leading.
Wood was set to make it three wins in a row for Scott in the 1914 event when he hit mechanical problems. Even so, Scott had proved his bikes’ ability and the distinctive two-strokes became very popular, especially, as a later report put it, with the professional classes who ‘appreciated sophistication, refinement and the finer things in motorcycling’, as well as excellent performance.
Part of the appeal was that Scott’s production machines were very similar to the racers, except that they were not fitted with the rotary induction valve. The Squirrel sportster, launched in 1922, was a great success, as was the Super Squirrel of three years later, still with the trademark ‘biscuit tin’ fuel tank.
This front view shows the liquid-cooled two- stroke ’s radiator on this most distinctive of bikes. Exceptional straight-line performance was backed-up by sound handling that helped keep the twins competitive and popular during the 1920s.
Scott’s motor featured angled-forward twin cylinders with a central flywheel, forming a stressed member of the tubular steel frame. This 1912 engine w
This 600cc Scott dates from 1928 and features a hand-operated 'gate' gearchange. The bike's large so-called 'biscuit tin ’ fuel tank is finished in the firm’s traditional colours of purple with silver bands.
Scott Two-Speed Specification (1912)
- Engine Liquid-cooled two-stroke parallel twin
- Capacity 532cc (73 x 63.5mm)
- Maximum power 3bhp approx
- Transmission Two-speed, chain final drive
- Frame Steel twin cradle
- Suspension Telescopic front; none rear
- Brakes Stirrup front; shoe-on-sprocket rear
- Weight 200lb (91kg)
- Top speed 50mph (80km/h)
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