Four wheels and wartime

More development,then into war, making armaments and overhaulingaircraft engines.

ince the first JAP engines, John Prestwich had hugely furthered engine designs, yet his restless mind retained the capacity for ever more development work. And many imply AE Bowyer-Lowe -who'd joined JAP as a 17-year-old in 1903-had not only become an able accomplice, but also was a superb race-engine builder.

Prestwich's 'further work' included cyclecar development cl912/13, with JAP building at least two complete prototypes, the latter serving over a large mileage as his wartime transport. Some suggest JAPwould have started a cyclecar production line had not the war intervened, though evidence of this is sketchy.

By autumn 1912, over 20 cyclecar and three-wheeler makers employed JAP motorcycle engines for some or all of their production, including Morgan, Arden, Sabella, Whippet and Invicta. Overseas makers were also using JAP engines for motorcycles, three-wheelers and cyclecars.

Realising the need and potential of this market led to the development of a lOhp inlet-over-exhaust valve 90 degree air-cooled V-twin of initially 965cc, though cyclecar makers' specifications imply other capacities were supplied too. Matchless were among the first to use this engine, displaying a prototype at the 1912 Olympia Show, though few were made.

With over 50 British motorcycle, threewheeler and cyclecar makers using JAP engines, both in air-cooled and water-cooled forms, plus a sound export market, it is fair to state JAP rested on their laurels while developing in other areas. For example, their ohv cylinder head/valve gear design hadn't been developed, and Swiss based rivals MAG were on occasions overtaking them in the market place and on the track. It is believed Prestwich began to remedy the situation as war approached, even to the extent of their believed testing and use at Brooklands.

JAP engines were employed for some motorcycles supplied to the War Office, including 6hp Royal Enfield, New Imperial and Sunbeam, all fitted with the 770cc JAP side-valve V-twin engine.

Around the same time, few noticed young

Valentine (Val) Page, who later designed many superb engines and machines, join the Tottenham works as a draughtsmen. However, with much of the works given over to the manufacture of armaments, many women were not only working full shifts while menfolk were serving on the front, but also back-to-back shifts, too. Although JAP engine production continued, the publicised range was reduced to just six engines, but it's believed a few special orders were serviced too.

While water-cooling was dropped and the range of engines and options reduced, nothing was ever cast in stone at JAP,thus if the customer requested something (and had

the funds to pay for it) their demand could well have been met, even in wartime.

As the world progressed through 1916, JAP unveiled a revised automatic oiling system ('The JAP pressure oiling system') available for V-twins using revised crankcases, although not all customers opted for this. And the company was again involved with aircraft engines, this time repairing and rebuilding to Government contract. Plus, JAP also stripped and examined 'captured' units all of which if possible were bench tested at the North London factory. Often this work went on 24 hours per day - oh, what great joy that • must've been for their neighbours!