Dutch Treat

DUTCH TREAT

Yamaha XS street-tracker

YOU MAY NOT RECOGnize Lee Von Der Hey's name, but you’ve likely seen his work in films and on television.

His area of expertise is set construction and special effects, the greater the detail, the better. The airplanes he and his team created for the 2001 blockbuster Pearl Harbor, for example, had wingspans up to 12 feet in length and flew by radio control. Due to their highly technical nature, they also were time consuming to build.

“Originally, production wanted 250 models, including 60 Japanese Zeros,” says Von Der Hey. “But when we delivered the first one, they said, kWe don’t need any more Zeros.’ They duplicated it with computers. Basically, computers killed our industry. At one time, we had 4000 model builders in Los Angeles; now we have 300.”

Having seen the writing on the wall. Von Der Hey is transitioning from models to motorcycles-and bringing with him his trademark attention to detail. His first creation under the Modern Vintage Motorcycles banner ( www. modernvintagemotor cycles.com) is a stunning blue street-tracker based on the mid-Seventies Yamaha XS650 inline-Twin.

Choosing the XS650 was a no-brainer. “I don’t want to throw BSA and Triumph under the bus, but Yamahas don’t leak,” Von Der Hey chuckles. Plus, Kenny Roberts won a couple championships with them.

“It’s a good engine, very well-designed,” he continues. “Stock, though, it’s not very torquey. The 750cc bigbore kit and hotter camshaft give it a lot more oomph. With the 34mm Mikunis and the custom exhaust, I probably doubled the horsepower with no loss of reliability.”

Similar reasoning dictated use of the stock frame. “I could have constructed a frame from scratch, but other issues—liability, serial numbers, etc.-would have come into play. It was a lot easier this way, plus the frame and engine numbers match.” Also, a real flattracker can be a handful on the street; the stock frame has a little more rake, a little longer wheelbase. “It still looks like a dirt-tracker,” says Von Der Hey, “but it’s more docile-handling.”

To damp out engine vibration, the XS’s Achilles heel, Von Der Hey went back to his model-aircraft-racing roots. “We run single-cylinder engines that turn 30,000 rpm, and we’ve learned to isolate everything from vibration,” he says. “The engines are hard-mounted to the fuselage so we rubber-mount all the radio equipment, the fuel tank, etc. Otherwise, they won’t last very long.” Much of the XSR750, from the Champion-style gas tank and Harley XR seat/fender to the wiring nucleus (tastefully hidden behind the front numberplate above tiny but highly effective halogen headlights) got a similar treatment.

Possibly the toughest hurdle was “balancing” the charging system so it didn’t underor overcharge the custom underseat battery. “The battery has 11 1.2-volt NiCad cells, which comes out to 13.2 volts,” he says. “The charging system cuts off when it reaches 14 volts, so the battery always has a good charge-unless, ahem, the studio photographer leaves the lights on!”

Where from here? Von Der Hey plans to build 10 more Yamahas (six have already been spoken for), each selling for $15K, then make 10 Forties-style hardtail Indians. After that, he wants to do a Dick Mannreplica Matchless G50.

“Computers are great tools,” sums up Von Der Hey. “They can create things that defy physics and exceed the wildest of imaginations. But they can’t duplicate the smell of castor oil.”

Matthew Miles