Friday, March 20, 2020

Royal Enfield's little motorcycle was his 'Royal Baby'

Five men, one of them seated on motorcycle, in front of building.
Joop van Heusden on the Royal Baby at Royal Enfield works in Redditch, Britain. From left are Royal Enfield's Major F.W. Smith, managing director, and technical manager R.A. Wilson-Jones; Stokvis & Sons head mechanic R. De Vries; and Royal Enfield works manager H.T. Guise.
Second of three parts.

It was a severe blow to lose the lucrative license to sell the popular DKW RT98 in the Netherlands. It was insulting, too, considering all that R.V. Stokvis & Sons company of Rotterdam and its technician Joop van Heusden had done to improve the DKW motorcycle.

Stokvis director Egon Ericsson wasn't going to stand for it. He asked Royal Enfield to help.

Going to Royal Enfield, in England, to request that it build a replacement for "The Little Wonder," made business sense. The two-stroke poppers were real money makers, thanks to Dutch tax laws that favored very small motorcycles.

The 1938 German decision to award the DKW business to a competitor (because Stokvis had Jewish directors) would backfire on the Nazis. The Royal Enfield RB125 "Royal Baby" would go to war with the British as the Royal Enfield Flying Flea.

The Royal Baby, one modern Dutch magazine wrote in 2019, was a form of resistance to the Nazis: "a thick middle finger."

For Joop, going to Royal Enfield was also a dreamed-of opportunity.

Joop and his staff at Stokvis had promoted and raced the DKW RT98, suggesting improvements to the factory. Enlarged cooling fins, improved clutch and gearbox and greater precision in the finishing work were among the results, and Joop and his technicians began to feel it was "our machine."

Three motorcyclists lined up at competition.
A determined Joop, center, with his DKW RT98 competition team.
Stokvis director Egon Ericsson is the man standing behind him.
DKW hadn't taken all of their suggestions, of course. Going to Royal Enfield for a replacement meant a chance to start all over again — but with the knowledge to make an even better motorcycle.

It was like being 10 years younger, Joop wrote, in 1939:

"We were 20 again — remembered what we know now — and our ideal? Our light machine? Well, the Royal Baby is almost identical with what we thought was the most ideal light motorcycle. And knowing what a care was taken both in construction and in the choice of applied materials, I can personally assure you that our new Royal Baby is closer to this ideal than any other creation in this area."

It wasn't easy, of course.

"It was a very rewarding task to convince the constructors at the Royal Enfield plant that it was not the bicycle as a basis, but the motorcycle as the basic idea that had to be used here," Joop wrote.

"The main features of a motorcycle; and therefore a motorcycle frame with a real ball head, consisting of a forged one-piece steel lug and with enclosed headset bearings instead of jammed headset heads, motorcycle brakes, really watertight, and rear brake being the most used by laymen, even with the stiffening rib; motorcycle wheels with spokes with weighted heads, strong rims and real balloon tires.

"The frequently occurring defect of spoke breakage was eliminated by punching the spoke holes in the rims in the right direction, while steerability was greatly served by applying the English Dunlop 19X2.50 tires, as a real motorcycle profile demands.

"Logically, the rubber-band springs that we created were also adopted and the handlebars were fitted with thin, easy-to-grip handles."

Small motorcycle.
The Royal Enfield Royal Baby was close to Joop's "ideal" light motorcycle.
Like the DKW, the Royal Baby would use a two-stroke motor. With only 125cc Joop couldn't afford the luxury of the four-stroke's empty rotation just to operate a valve train.

This would mean having to mix oil and gasoline when refueling, a serious inconvenience, but Joop rationalized that high fuel mileage would make this operation less frequent.

Their knowledge of the DKW RT98 gave the Dutch technicians ideas for the ideal shape of cylinder and piston, ignition system improvements and gearbox design.

"The same concern will be found in the beaded edge of the gas tank, which will prevent damage to the cables, the sealing of all bearings and pivot points, whereby grease leaks will be excluded, and countless other trifles," Joop wrote.

Joop favored the tank-mounted shift because novices need both feet on the ground for balance — so a big tank, which would force a foot shift, was out. He was against such luxuries as swinging rear suspension, sidecars, full-size headlights with built-in speedometers, and "overly large brakes."

It all took less than six months. The Royal Baby was born.

"The British Lion is startled awake," wrote the Dutch magazine "Motor." There was talk of a "British invasion," meaning an attractive new motorcycle coming onto the Dutch market.

It was now May, 1939.

In one year, German troops would invade the Netherlands, occupying the whole country for five years. More than 200,000 inhabitants would be victims of war, more than 100,000 of them victims of genocide. Perhaps another 70,000 would die, starved of food or medical care.

"Motor Joop," as he was called, would die in 1943, shot by a German soldier.

The Royal Baby would live on, to fight back.

Part 1: The heroic Dutch man behind the Flying Flea.

Part 3: The Flying Flea.


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