Technology is a curious thing. Like a wildly spinning top, it veers in a thousand directions, knocking everything it comes across out of its path and sending them flying off at a million tangents. It is as contagious as the common cold, and just as variable; as easy to control as a herd of eels; and as predictable as a ping-pong ball in a hurricane. Take any given technology and chart its progress, and twenty years later, it is doing something unimaginably different from the aims of the people who conceived.
This is the underlying lesson to be drawn from Mat Oxley's latest book, Stealing Speed. The book tells the story of how the two-stroke engine came to dominate motorcycle racing, and of the two men who brought about that immense change. They both changed the course of history and were swept up in events even more momentous, bringing about the ruin of one motorcycle manufacturer, the rise of another, while driving a third almost to the brink of madness in its stubborn resistance to the tide of history. The tale revolves around two men, Walter Kaaden and Ernst Degner, one the man who turned two-stroke engines from discarded relics into high-powered racing machines, the other the brave recruit who raced them, then turned traitor and sold the technology to the Japanese.
Kaaden took three ideas and combined them into a magic formula for the two-stroke engine. The first, he took from one of the grimmest weapons of the Second World War, the V1 rocket or doodlebug. The rocket used a pulse jet engine, basically a series of controlled explosions in a specially-shaped chamber producing thrust, and Kaaden's time spent at the German rocket base of Peenemunde at the end of World War II as a test engineer laid the germ of an idea which he used when he returned to producing motorcycles with IFA (formerly the DKW factory, before it was taken over by the communists after German partition). Here, Kaaden discarded the old megaphone exhausts previously used on two strokes, and set about designing and building the expansion chamber, using the same physics of resonant harmonics he had learnt while working on the V1's rocket propulsion.
