Changing times

As the Roaring Twenties drew to a close, JAP focussed heavily on improvements, including to lubrication, though, happily, they still found time for the odd whacky engine.

- RICHARD ROSENTHAL

Even in the depressed late 1920s, many Brooklands and TT racers opted for new JAP engines. This was partly because JAP delivered good power and usually remained in one piece, but, also, the factory offered their latest TT/Brooklands motors in early season.

These often followed standard designs, but if makers/buyers wanted specific modifications, often they got them. In 1927, over 30 TT entries used JAP 246cc, 346cc or 498cc ohv single-cylinder engines. Some riders used older engines, but the new motor’s specifications included revised main bearings and big end assemblies, valve/valve gear modifications and more.

Again this development paid off when Freddie Dixon (HRD-JAP) won the year’s Junior race, after race leader Wal Handley’s Rex-Acme melted its Blackburne engine’s piston.