Road Test No. 90 AN EW
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THREE -WHEELER TESTED
WHEN a commercial vehicle is used in circumstances which include only a small or moderate annual mileage, it is usually the case that the standing charges are considerably greater than the running costs. If the nature of the work be such that the maximum load is not great, there is, consequently, much to be said in favour of the three-wheeler on the score of economy.
To obtain the full benefit in this direction, the unladen weight of the vehicle must not exceed 8 cwt., the limit for "motorcycle" taxation.
Until comparatively recently such machines have been constructed only for loads up to about 5 cwt., but the Fleet is built to handle half-aton. It, therefore, represents a new class of vehicle, of which this is the first road-test report published in this country.
Throughout the world, Aridl motorcycles are well known, and Fleet Motors, Ltd., of Selly Oak, Birmingham, is, so to speak, an offshoot of that concern. The Fleet three-wheelers are, in fact, made in the well-equipped Ariel factory, and have behind them some 35 years' experience in the production of motor vehicles of various types.
A description of the Fleet was published in the issue of The Commercial Motor dated November 17th, 1931; it will, therefore, be sufficient now to recall the outstanding features of the design.
The chassis frame, although reasonably light, is particularly robust and is well provided with crossmembers. Special "progressive loading" semi-elliptic springs are mounted on the Ackerman-type front axle; at the rear a substantial arm, pivoted in large plain bearings, carries the driving wheel, Its suspension takes the form of a quarter-elliptic leaf spring. All three wheels are interchangeable. Power is derived from a singlecylindered air-cooled engine with side-by-side valves ; a turbo fan mounted on the mainshaf I ensures a cooling draught around the cylinder and head. Following accepted motorcycle practice, the transmission system consists of a roller chain from the mainshaf I to a clutch-and-gearbox unit, a second roller chain connecting up with the back wheel. There are three forward speeds, as well as a reverse ratio.
In general, the controls follow car rather than motacycle practice, although the driver's position is reminiscent of that of the latter type of machine. The driver sits on a sprung leather seat, mounted above the engine, on a substantial metal pressing which covers the entire mechanism.
On the near-side floorboard is the clutch pedal, whilst the brake pedal and the accelerator are operated by the driver's right foot. Mounted on the dash is a 16-in, steering wheel with its axis almost horizontal. Close to it, also on the dash„ are the Bowden-type ignition control and the horn. button, Whilst the electric light switch, ammeter, oil gauge and speedometer (the lastnamed costs an extra £2 5s.) are grouped, neatly in a panel.
Slightly behind the driver and to his left . the hand-brake lever, which, nice the Pedal, is connected to the three Sets of shoes, one pair in each hub. • These are of Bendix servo type.
For starting purposes, a strangler Is fitted to the Amal carburetter,
whilst there is also a slow-running adjuster. These two controls, not -being normally required when driving, are placed under the pressed " bonnet " already mentioned, and can be reached through a gap on the oft side.
Two types of body have been standardized. The closed van has double doors at the front and a third door on the near side towards the rear. Itscapacity is 50 cubic ft., the internal dimensions being 5 ft.
2 ins, long by 3 ft. wide by 3 ft. 3 ins, high, not includ ing the slightly arched top.. Its price complete is £87 10s.
The open truck has the same length, a width of 2 ft. 11 ins., and sides 2 ft. 3 ins, high. Its front can be dropped after the manner of a conventional tailboard. Its price is /85.,
Examples of both types were tested, and it may be said that there is very little difference between their respective performances, when equally loaded. The weights given in our usual data panel refer to the closed van; it should be noted that the truck body is approximately 40 lb. lighter. Despite the size of the van, the driver has an adequate view of the road, by reason of his rather high seat. Contrary to our admitted expectations, no difficulty was experienced in negotiating traffic.
At first the rather lofty seat— lofty, at any rate, for a vehicle of this size—engendered a slightly precarious feeling, but this rapidly disappeared as we realized that the machine is thoroughly stable. No special care is necessary when cornering, and the Fleet was turned around on a gradient of 1 in 5 without the slightest risk.
From observations made when following one of these vans, it can be said that the Fleet is quite free from that old three-wheeler vice—a marked tendency for the rear wheel to lie over when cornering.
In top gear the engine pulls comfortably at any speed from 12 m.p.h. up to its maximum of 34 m.p.h. It is, however, desirable to use the ignition control when the lower limit of engine speed is approached. The cooling system appears to function satisfactorily, and has the advantage that it is as effective on the indirect ratios as in top gear.
Turning to the performance on the lower gears, it should be stated that the change from one to another is easily made and little skill is required. This is, of course, a usual feature of the motorcycle type of transmission system. For use in hilly country, where it might frequently be necessary to change down from the middle to the bottom gear, it would be an advantage to have some sort of stop arranged so that the gear lever could not readily be brought back too far. As things are, it is, perhaps, a little too easy for an inexpert driver to place the lever, unintentionally in neutral on a steep hill, with consequences which might well be awkward.
0111 the whole, hill-climbing is good. As is to he expected with such a low power-weight ratio, the gearbox must be used; but, with its aid, no difficulty should be found In climbing any gradient which is likely to be encountered by a machine of this type in normal use.
Gough Street, well known as one of Birmingham's steepest streets, can be conquered with power to spare. As a sterner test, the machine was driven without a falter s4.2 up a hill of 1 in 5. On the same gradient, it was just possible to restart, with the aid of a little clutch manipulation. With approximately half the maximum load, the same test was completed without serious difficulty. It must be remarked that few delivery vans would be called upon to climb such a hill. Still fewer would be required to stop On it, Acceleration is, in general, good. When top gear is engaged, speed can be gained quickly enough for normal driving. To take advantage of traffic openings, second gear is naturally required. This is a useful ratio with a speed range from about 4 m.p.h. up to over 20 m.p.h.
Even more essential than acceleration, for a vehicle of this type, is braking power. In that respect the Fleet is distinctly good. The actual performance is shown in the form of a graph reproduced on this page, but mention must be made of the smooth and even action of the Bendix servo brakes. No matter how violently the pedal is depressed, there is no tendency to pull the machine off its true course.
The suspension system. is good, and the Fleet holds the road well.
For the driver, ample protection is provided by the safety-glass windscreen and the hood. At an extra cost of £2, rigid side curtains can be obtained, and these, too, are effective.
Briefly, our impression of the, Fleet three-wheeler is of a robust vehicle capable of standing much hard use and abuse without giving trouble. It is also capable of doing • its work with the least possible delay, and of saving its owner a useful sum of money by reason of its low taxation, low insurance, low capital charges and low running costs.