Paul Dunstall was a specialist tuner of Norton twins in the
1960s and early 1970s. He started modifying Nortons in 1957, at the age of 18,
when he converted a Norton Dominator into a competitive racing motorcycle. As
well as fitting a Norton Manx gearbox and wheels, Dunstall balanced the
crankshaft and installed the Dominator engine into a Manx Norton frame. With
places and two outright wins at Brands Hatch in his first season, after
graduating to a higher level with places in his second season at other circuits,
Dunstall retired from racing to work in his family's scooter shop and develop
performance motorcycle parts
Initially Dunstall conceived simple 'bolt on' modifications such as 'Goldie'
pattern straight-through replacement silencers which he called 'Hi-Tune' and
exhaust pipes, creating his first catalogue in 1961 and gradually growing the
business.
Dunstall built engines for other racers and purchased parts left over from
Norton's Domiracer project when the factory closed in 1963, using his know-how
to further develop high performance motorcycles built to order.
From 1966, Dunstall's customers could choose from a standard catalogue offering
a range of speed parts, race-styled accessories and complete ready-modified
bikes[4] from Norton, BSA, and Triumph in capacities from 500cc upwards.
In 1966 Dunstall Motorcycles became a motorcycle manufacturer in its own right,
so that Dunstalls could compete in production races and the Auto-Cycle Union,
which is the governing body for motorcycle racing in Britain, approved Dunstall
Dominators as a marque for the production race in the 1967 Isle of Man TT.
The last bikes from the featherbed-based machines in the 1969 catalogue were
stated as Dunstall Norton Sprint and Export 750 together with the newest bike in
the range the isolastic-framed Dunstall Norton Commando.
By the late 1960s, Dunstall had sold to celebrity customers including film star
Steve McQueen and Keith Emerson, of progressive rock band Emerson Lake & Palmer.
After the 1968 race season successes, development of the late-1940s designed
parallel twin engine was nearing its zenith for the technology of the time with
power outputs of 73 horsepower for the race-spec 745cc Atlas-based engine.
For the 1969 season, Dunstall created a new machine with a lower frontal area,
the inclined engine being 'underslung' from a large-diameter steel tubing spine
frame (nicknamed The Drainpipe) designed by Eddie Robinson The main frame
component ran front to back with a second large-diameter vertical tube at rear
of the power plant carrying the engine oil, avoiding the need for the
traditional separate oil tank. The filler was conventionally placed ahead of the
seat nose.
Although Dunstall's open-class racers (non production-race category) were
equipped with lowboy frames based on the works design which Dunstall had
acquired during the Norton factory race-shop closure, this re-design was based
on an established concept not yet applied to the Norton twin for road racing.
With no front downtube(s) hence no conventional engine mountings, the spine
frame needed substantial cantilever bracing from the central-point of the frame
forwards under the gearbox and engine to control the torque reaction
The original 'drainpipe' configuration included aluminium dual 'pannier' fuel
tanks inside the top-half fairing sides to lower the centre of gravity and
improve handling but following fuel starvation problems a conventional fuel tank
was fitted.
Motorcyclespecs.co.za Terms of Use: All original, copyrighted material like all specification sheets and some of the articles may not be copied, cut and pasted,
published or otherwise reproduced in any way in any medium, which means, don’t post this on another website. If you want somebody else to see this, send, share or tweet a link or post a link to this page. Some country's motorcycle specifications
can be different to motorcyclespecs.co.za. Confirm with your motorcycle dealer before ordering any parts or spares. Any correction or more information on these motorcycles will kindly be appreciated. Any objections to sourced articles
or photos placed on motorcyclespecs.co.za will be removed upon request. Contact PolicyLinks