Key engineering advance #5: Water cooling

The very first internal-combustion motorcycle, built by Daimler and Maybach in the 1880s, was water cooled, but it also had four wheels. The first two-wheeled motorcycle with a water-cooled motor may have been the 850cc Wilkinson TMC built around 1910. It leaned to turn, but had a steering wheel and a chair instead of a saddle, so it was also perhaps too car-like to truly be called a motorcycle.

Scott's bikes were so advanced that an entire lifetime later, a direct descendant of his early water-cooled two-stroke twin was used to power the ill-fated Silk...

In 1914, the Scott TS set a surprising precedent. It had a 486cc two-stroke, twin-cylinder motor that bore an amazing resemblance to sport bikes like the Yamaha RZ350, produced a full seventy years later.