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Norton Dominator 88
Inspired by the popular success of Triumph's
prewar Speed Twin, and aware that other factories were working on their own
versions, Norton realised that if they were to have any future after World War
2, they too needed a twin engine.
The job was undertaken by Bert Hopwood, who had
worked on the development of Edward Turner's original Speed Twin design and had
a vast experience in the industry. In 1947 Hopwood laid out his design, which
aimed to improve on the Triumph's weaknesses, such as poor cooling, and
incorporated some new ideas of his own. Chief among these was the use of only a
single camshaft for inlet and exhaust valves, in place of the two used by
Triumph and all the other factories.
The design had to work within the constraints of
Norton's antiquated manufacturing machinery, as well as running on the poor
quality post-war 'Pool' petrol. And for reasons of economy, it had to fit into
the existing single cylinder model's frame. Such thoughts as these were behind
the choice of a single carburettor, with close inlet ports and splayed exhausts.
Fitted into plunger cycle parts from the
range-leading ES2 single, with some cosmetic changes including a special tank
and mudguards, this became the Norton Model 7 Dominator, launched in 1949.
With a soft tuning, it offered little real
challenge to Triumph's twin - but it could still reach 90mph and offered
excellent reliability and handling in the Norton tradition. It was phased out in
1956, having long been overshadowed by its replacement, the De-Luxe, or
Dominator 88, which first appeared in 1953. What made the 88 special was its
frame, a close copy of the successful 'Featherbed' used on the works Manx Norton
racers. Weighing some 401b less than the Model 7, it handled and went rather
better than its predecessor.
In 1956 the 88 Dominator's engine received the
benefit of some serious performance development. The engine was resized by
enlarging both bore and stroke to give a new capacity of 600cc. Its power output
went up from 29 to 31 bhp and the new model was given a new name, the Dominator
99. With a hotter camshaft and higher compression ratio, plus new carburettor,
the model's number roughly equated to its top speed. There were also frame
refinements to match the performance.
The next important change was in 1961-62, when a
new 49 bhp 650cc model was announced and both the 88 and 99 came out in SS
(Super Sports) versions.
The 600s were soon discontinued and in 1964 the first of a series of 750 models,
the Atlas, appeared.
Specs
Norton Dominator
Years in production: 1956-62
(Dominator 99) Engine type: parallel twin ohv
four-stroke Capacity: 596cc Bore and stroke: 68 x 82mm Compression ratio: 7.4:1
Power: 31 bhp @ 6500rpm Carburettors: I '/iğin Amal 376 Ignition: coil
Wheelbase: 56'Ain Weight 3951 b Top speed: 101 mph |
