Competition and Race Shop

The AMC Race Shop was a single-storey building located separately from the main factory, on the opposite side of Burrage Grove.

The road-end of the building was allocated to the Competition Department, comprising two fixed-height bike preparation benches where scrambles machines were built to the specific requirements of works riders such as Vic Eastwood, and separately managed by Wally Wyatt.

The remainder of the building was under the control of development engineer Jack Williams who had his office at the rear (under a mezzanine floor where the race shop spares were stored), and looked out onto an engine assembly area, comprising assembly benches on one side with a lathe, cam profiling machine and various small machine tools along the other wall.

In the centre of the building, arranged at an angle, were several fixed-height bike building benches where the highly-skilled, specialist personnel took meticulous care in their preparation of 7R and G50 racing machines, often under pressure before major events, such as the Isle of Man TT races.

Outside, beyond the rear wall of the race shop, two water dynamometers were housed in separate underground caverns, accessed by steep steel ladders, where engines were tested for power output behind steel mesh guards.

Large diameter 2-speed fans, drawing in air from the roof, were positioned in front and behind the open-exhaust engine to provide air cooling at speeds up to 95 mph.

Readings were taken by the (well-earmuffed) testers of the brake output, speed, fuel consumption, barometric pressure, etc.

(Winter was not always the best time for testing as, if it was snowing outside, the fans would blow snow onto the test bed).

Fortunately, the exhaust noise from the test pits exited onto a railway line and not near to any housing, or the race shop would have received quite a few complaints from otherwise fairly tolerant neighbours.

The water dynamometer works by forcing water, under pressure, through
the central vane (detail 1). By closing the brass cups over the central
vane, the complete outer casing is caused to tip.
To counteract this, balance weights are hung on the rear and the inch
scale adjusted to align the pointers (details 2 & 3)
Readings of weight, distance and RPM allow calculation of the output of
the engine on test.