Denny Berg and the Copper Chopper

Taking a spin on one of Cobra's stunning customs. By Jamie Elvidge.

Photography by James Bown...

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Have you ever wondered what it would be like to ride one of those super customs you see at shows and in magazines like this?

When Cobra Engineering unveiled the latest work from its master builder Denny Berg at the 2002 Indianapolis dealer show no one oohed or ahhed. That's because this stunning chopper takes your breath away upon first sight, making even simple utterances impossible for a second or two. The congratulatory chatter soon followed though, and once again Cobra's latest custom was the envy of the event.

Using a four-cylinder Honda...

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I can't remember how many of the eights years they have done this that I've stood there post-unveiling, cranking my jaw back into place while vying for a chance to question the Cobra team about its latest marvel. Cobra has become almost as famous for these extreme customs as it is for its innovative accessories. The bikes are worlds apart from the showcase customs other aftermarket companies come up with, and the designs are consistently unexpected. We spend all year debating about what the next Denny Berg bike might be, and time after time we're left slack-jawed.

Chatting it up with Denny Berg is always a delight, especially when the beans are good to pour. Although he's very, very good at keeping Cobra's secrets, we believe it's excruciating for him when he can't talk about his latest projects. Denny is a 24/7 motorcycle guy. His is the kind of passion that's thicker than 50-weight motor oil. If you saw him on the street, however, you'd never take him for a fanatical biker. Instead, you'd simply want to take him home to meet your daughters. For a genius, he's pretty darn unassuming. And as an artist, Berg's anything but pretentious. Laid-back, yes. Persnickety, never.

Copper Chopper highlights...

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When I had Berg to myself at Indy, I asked him the usual. "Whence the idea for a four-cylinder chopper? How difficult was the project? How long? How much? How many...?" I slipped in a "When can I ride it?" for good measure, fully assuming this Cobra bike would move straight to the show circuit, or some frou-frou museum. "Come out to my place in Palm Springs and we'll take it to my new favorite biker hangout" wasn't what I was expecting to hear. (A strap for the jaw would be really nice, you know? It could loop right around your ears and match your outfit.)

Berg's hideout in Palm Springs, California, is tiny, but tightly organized. Denny insists that a builder doesn't need much space, just a good idea and the right tools and materials. Not only was the Copper Chopper there for my enjoyment that day, but also Cobra's exotic 1999 creation, Low Star with its tricky foot clutch.

The concepts for these wicked customs are a collaboration between Cobra's Ken Boyko, Berg and his cohort, renowned concept illustrator, Mike Rinaldi. Building a 1970s-style chopper with an inline four was something Boyko had wanted to do for a long time, and a perfect fit for Berg, who says he wishes he had a nickel for every chopper he built back in the '70s. The only thing that held up the project was finding the right motor. They considered using something older, but felt it would date the bike, and the new high-horsepower powerplants found in modern sportbikes were just too ugly. The Honda Nighthawk engine was a perfect solution because it's "beautiful, smooth and makes decent horsepower" but it's also pretty timeless considering Honda's been making the same version since the early 1980s.

"Choppers are a real simple recipe," Berg says. "If you went back to my doodles from high school that's exactly what this bike is—a massive motor with a spindly frame and a big back tire." When you get to know Berg you realize he thinks everything about customizing at his level is easy. "Yeah, right," we think as we humor him, knowing all too well that it's only easy for him.

Berg's all around expertise...

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An example is the fact that the Copper Chopper is a dream to ride—very much unlike any custom choppers we've ridden before. I couldn't believe how smooth and manageable it was in any situation. There was none of the sloppiness you'd expect, and none of the heaviness in the front end either. Not a blip of badness in the entire system. Just fun—major fun. But again, Berg will tell you in his perpetually cheerful yet ho-hum manner, "It's just a formula—nothing magical. If you get the geometry right—the rake and the offset on the triple tree, then add the right front tire—it makes the bike pleasant to ride."

He does admit that his professional history in motorcycling, which has included everything from building wildly fast cafe racers to world-class championship motocross bikes, has allowed him a special blend of knowledge. From the street-racing side he learned how to make horsepower and from the MX world he gained expertise in chassis balance and suspension modification.

Berg says that making a chopper this heartbreakingly beautiful isn't all that difficult either—just that some parts of the recipe are very important. "The front downtube, for example, has to be set at a complementing angle to the fork. If the fork is 38 degrees, you bring the front downtube back to 38 degrees. It's also really important that the line from the axle to the steering stem is straight. The rest is in the details, like not having the clutch cables doing some big arch or hanging on the frame with zip ties." While Berg is always quick to compliment other builders, he gets pretty judgmental in this one area. "People do such a good job doing a bike and then they blow it. I spend a lot of time routing cables through the frame and to me it makes a big difference. If someone has taken the time to think through the wiring when they were building the frame it impresses me."

Berg is as mild-mannered as Clark Kent on a slow news day, but some attitudes make him a little, ah, warm. "These poseurs buy a new Harley and think they are experts," he says, "and it irritates me when they look down their noses at you because you're riding something else. If you know anything about the history of choppers you know it didn't start with Harleys. In the 1950s, it was British bikes and in '60s and '70s, we were building choppers and cruisers out of anything but Harleys. If you pull out old chopper magazines from the 1970s you see Japanese bikes—and four cylinders, not V-twins."

Berg should know. He was building choppers in the late 1960s. At 14 he turned his first street bike, a 450 Honda, into a chopper even though his dad wouldn't let him extend the front end. "I just put a smaller front wheel on it and raised the headlight and tank so it looked like it had a long front end," he says. "I've always created illusions to get what I want." That wasn't Berg's first custom though. When he was just four he took the front fender off his tricycle, added some streamers on the bar tips and slathered it with house paint.

Here it is, the StrataCruiser...

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Berg thinks that being raised in rural South Dakota developed his focus and methodology. "Necessity is the mother of adventure," he says. "I didn't have access to custom stuff, so I was always walking through a hardware store, junk yard or tractor supply place, and I'd see a little piece and find a place for it. We didn't have a lot of money, but we had welders and big hammers," he says. "The poseurs miss out on the fun of making something personal. Anyone can look through a catalog and pick out parts that will look good to everybody, but it's not your own."

When asked about the next Cobra project, Berg pointed to a bunch of metal rods and tubing propped in a corner of his shop, "There it is," he said, and I knew it was true. At least partially. The core of the project, whichever model or motor Cobra has selected for 2003, had been tucked into some cranny so I wouldn't see. And I suppose I was glad. It would have ruined that moment next February when the sheet gets pulled off and my jaw hits the floor.

For more articles on custom bikes and articles about how to customize and modify your motorcycle, see the Custom section of MotorcycleCruiser.com.

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