I have an 810 Dunstal Norton which came with all Dunstall gear when I bought it in 1974. That included 810 cylinder, dunstall cam, 32mm amals, 2 into 1 into 2 exhaust with decibal mufflers, dual 9”discs, dunstall tank and seat, clip ons, dunstall front guard, fairing, 5 speed box, boyer ignition, 19”WM2 borani up front and 18”WM3 borani at the rear and a nickel plate frame. The one thing that makes me think the bike is probably original Dunstal rather than aftermarket, is the head. It has the revised valve angle to the inlet port and bronze guides. I don’t know that the heads with revised valve angles were sold aftermarket.
Over the years the fairing cracked and had to be taken off and left at the side of the road. The front mudguard was useless in the wet so I dumped it and fitted a more substantial guard. The boyer ignition packed up so I went back to points, the 5 speed box ended up having no teeth and was replaced with a 4 speed and the nickel plate on the frame started to peel so I painted it. So the bike now is missing some of the dunstall equipment. I have also eplaced the fibreglass sidecovers with later steel ones
The only engine modifications apart from Dunstall parts that I have done is head porting and cylinder shave. The Dunstall porting although enlarged to 32mm was the old fashioned flat port design. When I first got the bike it was lucky to give 30mpg. After having the inlet port reshaped by Claude Cartledge, a well known Sydney tuner, the power went up dramatically as did the fuel economy to 45mpg. The ports were altered by removing material from the roof, near the valve to accentuate a down draft and direct the incoming mix away from the exhaust port. The cylinder liners were below the top of the cylinder so I had the cylinder top shaved by about .020 which raised the com to about 10.5 to 1 which is probably a bit high. The bike always overheats in stop go traffic and the idle starts to race and become erratic but the bike runs cool on the open road with never a problem.
The bike is uncomfortable around town as there is too much weight on your wrists. At speeds from 55mph up however the wind takes the weight off your wrists and the bike becomes quite comfortable. I have ridden 700 miles straight only stopping to refuel without a problem. I used to regularly ride 300 miles between Sydney and Eden on the south coast in 4 hours. The good days before speed cameras and even before mobile police radar.
