1947 TRIUMPH &quot;GRAND PRIX&quot;.

After WWII, the Triumph race department fitted an engine designed during the war for an electrical generator into a racing motorcycle and won the 1946 Manx Grand Prix. Several more bikes were made and called, of course, the Grand Prix. Notice the lugs on the cylinder fins where the air cooling shroud for the generator use was mounted.

In September, 1946, Ernie Lyons rode a Triumph twin to victory in the Manx Grand Prix • the Island. Later that month the Triumph factory, with commendable "uickness, announced that a replica of the winning machine would be sold, as a stripped racer, in 1947. It would be known as the "Grand Prix".

The full story of the machine goes back to pre-war days, when Triumphs had marketed the first successful parallel twins—first the "Speed Twin", and then the "Tiger 100". After the war,

Triumphs were soon back into production with iron-engined models very similar to the pre-war ones except for the fitting of telescopic-forks.

Ernie Lyons took one of these post-war "Tiger 100s" and set about turning it into a real racer. (This had been done before the war as well—a "Tiger 100" holds the Brooklands 500 c.c. lap record for ever.) The main change he made was the fitting of the cylinder-block and -head from a W.D.-type generating-set engine; these were of light alloy.

The factory co-operated with him in his project by lending him one of the first spring hubs to be made. This now-forgotten method of rear suspension had coil springs encased within a large alloy hub so that the wheel could move an alleged 2 in. It was better than a rigid frame. . . .

The push-rod twin-cylinder motor undoubtedly had a great advantage over the single in races immediately after the war, for it took much more kindly to the dreadful petrol then available. The "Grand Prix" never scored any really great victories, but certainly gave scores of budding racers their first chance to straddle a machine built for racing.

The Triumph twin engine has an even greater claim to fame, for surely no other unit has been used in so many successful specials—or in so many unsuccessful ones. The "Tiger 100" engine's grandson, the "Tiger no", powered the fastest two-wheeler in the world up to 1961 (whatever the F.I.M. say!).

The history of the Triumph company dates from 1885, the year it was founded by two men of German origin, Bettman and Schulte, who made and sold high-quality bicycles.

Ten years later Schulte tried out a Hildebrand & Wolfmuller motorcycle. The new experience had such an impact on him that he and his partner decided to go into motorcycle manufacturing.

The first Triumph motorcycle to appear was the four-valve Type R. Designed by Ricardo, it went on sale in 1901. Triumph owed its first racing wins to the Ricardo model after its sensational performance at the 1908 Tourist Trophy.

In January of 1936 Triumph Motorcycles was completely restructured, and so was its production. The first Triumph motorcycles with two-cylinder engines began to appear. Ernie Lyons rode one of these to win the 1946 Manx Grand Prix. It was such a dramatic win that the Triumph people decided to produce a racing model that had the same features as the one Lyons had ridden.

Thus the Triumph Grand Prix made its first appearance in 1947. It was a substantially updated motorcycle with a powerful engine. Sold throughout Europe, it was victorious in a host of. minor races.

SPECIFICATION

Engine: parallel twin 500 c.c. o.h.v.; valve operation by

push-rods. Ignition: magneto.

Transmission: chain via four-speed gearbox.

Frame: cradle type with single down-tube and twin

bottom rails; rear suspension by patented sprung

hub. Forks: telescopic.