NOT stock and four smoking barrels

Kawasaki’s H1 triple was always a fearsome machine, so what happens when you add another cylinder to take the capacity out to 666cc? Triples fanatic Roger Ramm recruited the legendary Allen Millyard to help him find out.

At first glance, Roger Ramm’s machine is just another nice 70s bike, albeit well put together and very well maintained. Many will have passed by without giving it a second glance, as it can take some time, and a close inspection, for the brain to register the extra pipe and cylinder. Once the full extent of the work that has been carried out has sunk in, then one can fully be in awe of the end result.

Roger, having carried out most of the work himself, was determined to bring the H1 into the 21st century by adding modern brakes and the extra third of a power plant without losing the original looks and style.
He purchased the H1 from new, back in July 1973, and Roger, then 19, is still the only name on the logbook. It was two-tone green back then and lasted for all of six weeks before a combination of youthful exuberance and the bonnet of a Morris Marina saw the potential demise of his pride and joy. Luckily the machine was rebuilt, after much deliberation from the insurance company, (the Marina didn’t fare quite so well) and eight months later, Roger and the H1 were reunited on the road.

The broken arm and leg that Roger suffered, bouncing off the Marina, didn’t dampen his enthusiasm for the triple and he set about tuning it to further enhance the already staggering performance. Sprinting became an obsession in the mid-70s and the 500 speedily made its way up the quarter for four years, recording a best time of 12.19 seconds, with a terminal speed of 119mph.

During this period, many of the stock parts were junked in an attempt to save weight and increase performance. Among these parts were several very hard to find pieces like exhaust pipes, airbox and the grab-rail, something Roger was to bitterly regret 30 years on. Roger also used the bike as regular transport during the 80s before laying it up and neglecting it for well over a decade. Two years ago, Roger finally found time to take stock and have a look at the 500 that languished in his workshop. “It was in a terrible state,” he admits, “after all of the good times it had given me, this was how I had repaid it.”
Around the same time, Roger caught sight of the four-cylinder H2 owned by triples club member John Edge. “That H2 was the best bike I had ever seen,” he admitted. “It was simply superb, Allen Millyard had done the work to the engine and I wanted one, and immediately I knew what to do with the 500. A quick calculation revealed the resulting capacity to be as near as damn it 666cc and that was it, I was sold on the idea of a four-cylinder machine.”

The next step, getting Allen Millyard to take the job on, was the easiest. He just needed reassuring that it wouldn’t end up as a piece of workshop junk, and that Roger was capable of tackling the rest of the work required to fit the extended Kwak lump into the frame. Four weeks later the completed casings and crankshaft were returned to Roger’s workshop for the fun to begin. Thankfully, Allen had provided lengthy notes on what to expect when it came time to put it all together. Various parts were ordered or sent off to the relevant suppliers. Hagon built the wheels and supplied the rear shocks, while drawings were sketched for a new box-section swing-arm to be fabricated. Four, 32mm Mikuni flat-slide carbs were acquired and the basic jetting guessed at by Allen’s Performance of Nottingham, the price of the carburettor parts alone adding up to a shade under the cost of the bike in 1973.


With the motor now considerably wider on the left side by around a third, the casings needed squaring up in the frame by moving it several inches to the right. This in turn meant the all-important chain alignment would be out by the same amount; Roger fabricated a lengthened output shaft for the gearbox and supported this with an outrigger bearing support attached to the left casing. The result is a perfectly stable piece of engineering, more than capable of supporting the huge strains seen at this point of departure for the engine’s power.

Classic Motorcycle Mechanics October 2005 edition

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