Cars -
Graham Skillen
It is only in recent years that the concept of
front wheel drive in cars has become popularly acceptable. However, the
concept of front wheel drive has been with us since the earliest days of
motoring, after all in those days there was not guaranteed ‘way to do it’.
Obviously car manufacturers soon realised that it was preferable to steer
with the front wheels and this automatically led to rear wheel driving, a
simplification perhaps but probably the reason why. In the 1920’s front wheel
drive motoring was limited to a relatively few small production runs, with
the FWD Alvis being one of the first series U1( FWD cars with only a few
hundred produced.
The BSA company in the late 1920’s no doubt
examined all the layout permutations when they decided to enter the light
car/three wheeler market, then dominated by the Morgan. Two wheels at the
front was the popular configuration at that time, but driving through a
single rear wheel did mean a ‘motorcycle’ type assembly and a heavy driving
load on the single tyre. FWD offered an easily detachable rear wheel with no
oily chains - a sales ‘plus’.
So in November 1929 the BSA three wheeler
appeared. BSA designers had not restricted themselves to a FWD Morgan or
Coventry Victor, and introduced innovations such as a reverse gear, electric
start and full weather protection. Independent front suspension was another
benefit resulting from the FWD layout and ‘Motor Cycle’ of the day said ‘The
details of this vehicle are of such interest that it may be said to mark a
milestone in the history of the light runabout’.
The engine in
the BSA Three wheeler was based on the Hotchkiss designed 900 air cooled
V-twin (1021cc), used previously in the 1922 RWD BSA. This allowed the car to
be kept within the 8cwt weight taxation limit for three wheelers. The engine
was mounted with cylinders across the car and driving through a cork clutch
and conventional gearbox to a differential mounted midway between the front
wheels. Final drive was by shaft, flexible coupling and Hooke joints at the
front wheels. Two coupled brakes were fitted, one on the rear wheels and one
mounted to the right of the differential.
This extract from a
sales brochure shows the front suspension layout.
Earliest trikes did
not have any shock absorbers but these were fitted to all later models
apparently to prevent spring breakage. The diagram is taken from a 1935 Scout
brochure.
The suspension
arrangement remained essentially the same throughout the life of the vehicles
although later Scouts had outboard front brakes.
The BSA/Daimler
(Armoured) car manufactured during WWII had suspension of the same pattern,
but in 4 wheel drive form and somewhat more massive!