The 650ss was manufactured at the original Norton factory on Bracebridge Street only one year: 1962. After that the factory was shut down and production for 1963 and later came from the AMC works.
The 1963 and later Norton Dominator's quickly lost their Bracebridge Street personalities as AMC used up the old stock of parts and made detail changes to cut the cost of producing the bikes as Norton had.
The 1963 SS Nortons looked much like the 1962 models. As stocks of old Bracebridge Street parts ran out, AMC axed the satin chromed fasteners and other parts and switched to 12v electrics.
1964 saw big changes. The chronometric instruments and competition magnetos were gone. Zinc plated fasteners were in. The 88ss green and grey paint scheme was gone and it was painted the same as the 650ss, all black with a silver tank. The steering stop was welded on, a steering lock was added and all front-end parts were altered to fit a wider front tire. The tach drive was pointed straight upwards on a less nicely finished timing cover. The alloy collars on top the fork springs were changed to steel. Fuel tanks had their caps switched to the right side and the speedo in the headlight was phased out in place of mounting the instruments on a bracket above the headlight, first on export bikes then later for the home market.
The 650ss and 88ss were revered in their home market, and that is the only thing that kept them living as long as they did. After the 750 Atlas came to the USA in 1962, it is my guess that the only reason any smaller Dominator Nortons were sold there at all were either to qualify the 88ss for racing, or to fill the Berliner's dealer showrooms when they could not get enough Atlas bikes or there was surplus 650ss bikes that were not selling in England.
The Atlas was probably built mainly as a result of pressure from the USA importer Berliner, who was selling the bulk of Norton production. It was a compromise with it's heavy low-compression pistons giving it low power and more vibration, but it could be advertised as a 750, see it is bigger than a Triumph!
When Doug Hele was hired at the Bracebridge Street works to run the competition department the Dominator twins had their renaissance. He looked at the engine as a possible replacement for the Manx single unit and his development spawned the 650 Manxman, the Domiracer, the SS bikes and a lot of wins in production races.
When AMC axed Bracebridge street, Hele and most all other Norton key people and loyalists quit or lost their jobs.
Though the original Norton works was gone, the 88ss and 650ss stayed on and an argument could be made that they were the last true Nortons. At least they were the last Norton models that were the idea of the original Norton works before big business, money and marketing contaminated then erased what had been the brightest star in England's motorcycling history......
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