Norton 650SS: the best of the Dommies

The Norton 650SS was a 650 cc vertical twin motorcycle made by the Norton Motorcycle Company from 1962 to 1967. It was based on the Norton Manxman, a 650 built for the American market, and its initials stood for Sports Special. The 650SS was capable of 110-115 mph and quickly gained a reputation as the best of the Dommies.

Norton 650SS at a glance

Based on one source, the English Wikipedia article on the Norton 650SS.

History of the Norton 650SS

From the Manxman

Norton produced a 650 cc twin in 1961 for export only, selling it in the United States as the Manxman. It was finished in polychromatic blue with a bright red seat piped in white, plenty of chrome and a special exhaust system fitted only to the Manxman. The Manxman 650 produced 52 bhp, enough for a top speed of more than 120 mph, and a race machine developed by Heinz Kegler reached 150 mph and won races at Pebble Beach. Production began at Norton’s Bracebridge Street factory in Birmingham, but after the factory closed in 1963 it was transferred to the parent company AMC’s works at Plumstead in London.

The 650SS

A European-styled version of the Manxman was shown at the Amsterdam International Auto Show in early 1962 and went on sale in April that year as the 650SS. It used twin Amal Monobloc carburettors with intakes angled downwards, twin exhausts instead of the 99SS two-into-one, and a separately mounted speedometer and tachometer in place of the headlamp nacelle. The machine was finished with a black frame, a silver fuel tank and optional chrome mudguards.

In February 1962 the magazine Motor Cycling recorded a best one-way speed of 119.5 mph at MIRA with a 650SS, more than 10 mph faster than a rival Triumph Bonneville tested the previous summer. Norton discontinued its 600 cc models to concentrate on the 650SS, which was soon known as the best of the Dommies. The model remained in production until 1967.

Design and features

• Manxman engine: a 650 cc twin with 52 bhp in Manxman tune and a top speed of over 120 mph.
• Twin carburettors: Amal Monobloc units with downdraught intakes, a step up from the single-carburettor 600s.
• Road test performance: 119.5 mph at MIRA in February 1962, more than 10 mph ahead of a Bonneville.
• European style: separate instruments, twin exhausts and a silver tank on a black frame.

Norton 650SS versions

• Manxman (1960-1961): the American-market 650 with polychromatic blue paint and a red seat.
• 650SS (1962-1967): the European version with twin carburettors and twin exhausts.
• Kegler racing machine: a privately developed racer that reached 150 mph and won at Pebble Beach.

The 650SS was the fastest of the Norton Dominator family, and its 650 cc engine sat between the 600 cc models and the 745 cc Norton Atlas. More Norton motorcycles are in the Norton collection.

Sources

• Norton 650SS, English Wikipedia: development, performance, equipment