In the early days of dirt-track racing
Messrs. Comerford-Wallis Engineering Co.Ltd., of Thames Ditton, Surrey,
produced the Wallis Dirt-track Special, a machine which was used to a considerable
extent. It was designed to take almost any standard racing engine of 350cc.
or 500cc. Outstanding features in its design were the short wheelbase frame,
Wallis patent lug wherever great strength was required, a special design of racing forks with a very short movement, and the provision of nuts requiring only two spanner sizes for the whole machine.
However, as far back as 1929, when the Wallis was produced, it was obviously impossible to design a dirt-track machine approaching
Incidentally, all lugs are drop forgings and every joint is brazed. Reynolds
Aero qaulity cold-drawn steel tubing is used throughout. The rear forks
and seat stays incorporate the Wallis patent lug, which gives immense strength.
The fork has a pair of very stout and dead-straight blades, braced at the front by two thinner members arranged so as to constitute a rigid girder able to resist all torsional stresses. There are no side links whatever, the springing
being of a novel design. The fork blades at the bottom have telescopic prong members with internal springs. As may be noted in the illustration, the fork action is limited by flanges on the lower telescopic members to a very small movement. Immediately in front of the heavy upper lug joining the main fork blades is a split lug for mounting the handlebars, thus providing a good forward position and adjustment for any desired angle. A special shock absorber is provided, in addition to the Andre steering damper over the steering head.
Tank. - The tank, which is originally distinctively panelled in red, is mounted on rubber insulators to protect it from damage. It holds 1 gallon of fuel and 1 quart of oil. On the left-hand side is a Bestand Lloyd positive hand-operated pump with a 5/16-inch oil-pipe union for connecting the mechanical pump on the engine.
Transmission. - A countershaft is provided, but no clutch. The countershaft, which is a 7/8-inch-diameter nickel-steel shaft, is mounted on Timken tapered roller bearings, carried in a cast-aluminium housing. The two sproekets are splined to the coutershaft and have 42 and 15 teeth. Hans rynold chains of extra heavy type, maesuring 5/8 x 1/4 inch, are used for both primary and secondry transmissions, but a 5/8 x 3/8 inch chain is also available for the secondry drive, which may be arranged on the near or off side at the riders option
Wheels and Tyres. - The wheels, which are chromium plated with heavy rims and 10-gauge spokes, have Timken tapered roller-bearing hubs, and the front one has a knock-out spindle. The chain wheel has 52 teeth. The wheels are shod with 2 3/8-inch Avon or Dunlop dirt-track tyres.
- Included in the specification are dropped racing-type chromium-plated
handlebars, which are adjustable for angle and provided with an Amal twist-grip
for the throttle, with dummy to match; a special Lycett narrow Aero seat
with three-point suspension; a quickly detachable rear stand of pressed
steel; a lifting handle made of steel strip with mudguard running between
this and the bottom chain stay ; a quickly detachable, rubber-covered foot
rest, and a knee hook.
THE COMERFORD-SPECIAL JAP MACHINE
Messrs. Comerford-Wallis Engineering
Co. Ltd, who, it may be mentioned, are distributors of Jap racing engines,
market besides the Comerford-Special frame assembly and the Comerford racing
forks, a complete machine with a 498c.c. single-port Jap speedway engine,
inclined slightly forward in the frame. This machlne, is known as the Comerford-Special
Jap. It has a large-diameter straight-through exhaust pipe, a twin float
chamber, Amal carburettor with triple-gauze filter, and a racing B.T.H.
magneto with platinum-iridium contacts.
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