The Norton Manx was one of the most successful track racing motorcycles of all time, and it was capable of up to 150mph and sublime handling. The bikes were built from 1946 to 1963.
The 498cc single stayed competitive in the postwar years thanks to the McCandless featherbed duplex frame. The low centre of gravity and short wheelbase of this setup was designed to handle the demands of the Isle of Man TT course. An all-welded, tubular featherbed frame was sleek and trim which dispensed with the usual forgings and castings which added unnecessary weight.
Engineer Leo Kusmicki and Norton team manager Joe Craig tweaked the dohc short-stroke version of the Manx engine until it produced 50bhp at around 7000rpm. The resultant bike was a sleek racing package which weighed in at just 310lb, was capable of attaining 150 mph, and which proved ideal for the Isle of Man course and made the Norton Manx the preferred ride there for many decades to come.
The featherbed Norton Manx traces its lineage back to 1927 when Norton engineer Walter Moore designed the SOHC mill that Alec Bennett rode to a win in that year’s Isle of Man TT. The first DOHC version debuted in 1937, and between 1931 and 1954 these Nortons won all but two of the Senior TT races.
But it was the development in 1950 of a new frame designed by Rex McCandless which sealed the deal. McCandless’ double downtube steel cradle with a swingarm rear suspension gave the bikes supreme handling characteristics and influenced the design of motorcycle frames for many years to come. Norton rider Harold Daniell was responsible for the tag applied to McCandless’ frame. When he was asked what the bike was like to ride, Daniell said it was “just like riding on a feather bed.”
The featherbed Norton Manx models were offered for sale in 1951. Only 100 were constructed each season and they were immediately snapped up by the top riders of the day. The DOHC 350cc Model 40 and 500cc Model 30 were hand-built by a small team in the racing shop of Norton’s Bracebridge Street, Birmingham, plant. Each engines was run for two hours on a dyno before being stripped and rebuilt to insure the reliability of the machines. This attention to detail allowed the engines to last an entire racing season without being stripped and rebuilt, and a typical Manx engine will hold a tune a very, very long time.
These featherbed singles dominated international racing into 1963 until Mike Hailwood finally unseated the Manx riders on an MV Agusta.
Scottish racer Bob McIntyre tests a Norton Manx in the late 1950s:
Insuring your collectible or vintage motorcycle
You can spend a lot less, but if you plan to ride the bikes in your collection, the above pricing is a reasonable approximation of what you can expect to pay.