Bike Build: Harley Inspired Carducci SC3 Dual Sport
Like many motorcyclists, Jim Carducci was a man with a dream, a dream of riding a motorcycle he designed himself. But unlike many motorcyclists, Carducci actually went ahead and built that bike. And it’s a beauty—the SC3 Adventure Dual-Sport he designed has grabbed attention ever since it first appeared and was featured on BikeEXIF and various other media channels. Combining a Harley-Davidson Sportster motor with a highly capable adventure bike chassis, there’s no other machine like it. Here’s the story of how the SC3 came to be.
The Carducci dual-sport project had its origins in the early 1970s when Jim Carducci got his first motorcycle. Like so many other kids at the time, he started out with a Honda trail bike. But unlike those kids, he tore his XR75 apart as soon as he got it home, right down to the frame.
“That’s what started it all,” he says. “I just had a curiosity for taking things apart.”
Soon he developed a second curiosity—an interest in finding what adventures lay beyond his neighborhood. His second bike, a Yamaha DT100, enabled him to hit the road to find trails farther from home, even though he was only 14 and not legally allowed on the street. As an adult, bigger dual-sport bikes followed—a couple of BMW HP2s, several other GS models, several KTMs, a KLR, and an XR650L. “I got into a habit—bad habit, per my wife—of buying a new ADV bike every year for a while,” he says. Throw in an epic trip around Mexico and other tours with RawHyde, and Carducci ended up with a pretty good idea of what made an adventure bike work well.
With an interest in all things mechanical and a comprehensive knowledge of adventure bikes, Carducci found the final pieces of inspiration a few years later when he bought a Buell, his first motorcycle with a Harley-Davidson motor. Seeing what Erik Buell had put together was an inspiration. He liked the engine’s character and thought it had a lot of potential. So he set out to determine whether it would make a worthy dual-sport.
He then began to look at similar projects, finding things he liked and disliked, and that thinking led to planning. By 2011, the planning had led him to buy a 2003 Harley-Davidson Hugger, the basis for his project, despite his friends’ and family’s advice otherwise. “They told me, don’t do it, don’t waste your money, it won’t work,” Carducci says.
Carducci used his earlier experiences on a wide variety of ADV bikes, along with his day job’s approach to designing semi-conductors, to decide how to proceed with the build. An engineer by trade, he went about the task methodically. And after finishing a 2D mock-up, he began designing the bones of the bike, beginning with the swingarm. Surprisingly, his bike would use a dual-shock set-up in the rear, unlike most modern adventure bikes, which utilize monoshock designs. “I went dual rear shocks for nostalgia since the bike was based on the older Evo 2003 Sportster motor and frame. It kind of goes with the style,” Carducci says. “That being said, once I decided on dual shocks, I also went high end with the Ohlins to make the bike work as well as it could.”
After mating his custom-made swingarm to the Sportster frame, he added triple clamps from a KTM 525, installed heavier springs, then took the rolling chassis out for testing. It didn’t take long to convince Carducci that he was on the right track; he rode the prototype on and off road and was surprised at how well it worked.
From there, the project took off in earnest. Carducci rented space in a local machine shop, Lux Manufacturing. Tackling the challenges one by one, he utilized the shop’s resources to help fabricate parts for the new design. Lux Manufacturing was a key part of the build, providing CNC machining for the components that Carducci designed.
“The first rolling prototype showed the thing was working pretty well. But I was kind of obsessed with it and just kept doing a part at a time,” he says.
The air-cooled Sportster motor meant he had to carefully design the front fender to allow air flow to the cylinder heads. Carducci also installed an oil filter with fins to help keep temperatures down. Now, he says the air-cooled motor actually works well, except for extreme cases of very slow off-road hill climbing on hot days.
The bike’s fuel tank is a thing of beauty. It’s obviously built to allow the rider to slide their weight forward and plant the front end. But looking at it, you wonder if it carries enough gasoline. Carducci says it does and has actually built two tanks; a plastic one-off made in conjunction with IMS, carrying five gallons of fuel, and another built with Evan Wilcox, a 6.3-gallon aluminum version. He says the Sportster motor gets better than 40 mpg, so despite each tank’s small profile, he gets a respectable 200-mile range.
Much of the rest of the bike is the same. The parts are either Carducci’s own design, or cleverly adapted from aftermarket suppliers. The front and rear suspension are from Ohlins (48mm USD forks up front, with a Scotts steering damper). The Hugger’s 883cc motor has been punched out to 1250cc, with Andrews N4 cams. The front brake uses a Beringer 6-piston caliper, radially mounted, with a 380mm disc. The rear brake has a four-piston Beringer caliper and 291mm disc.
Carducci had a stainless steel 2-1 exhaust header custom built by BTRmoto, and mated it to a Leo Vince exhaust, complete with spark arrestor. And there are two sets of wheels for the bike—a 21/18 combination for off-roading, and a 19/17 set for the street, built with Excel rims and a Rad front hub and Billet Boys rear hub. He’s also managed to make good use of a fair number of stock parts; his bike uses the stock Sportster frame with some minor modifications, along with the oil tank, switchgear, wiring harness, and other bits.
“I guess I probably had an obsession and spent way too much money on this thing, but it was something I really wanted to do,” he says.
All in all, it took Carducci about four years to complete the first incarnation of his bike, working nights and weekends at the rented shop space. The end result had little in common with the low rider he’d started with. He’d gone from the lowest Harley-Davidson model you could buy, to a towering ADV machine—but kept the powerplant he loved.
“Compared to a standard H-D, you still hear and feel that same motor,” he says. “I love the sound, and the torque is good, too. That’s about where it stops, though. On the road, this bike has a good lean angle, a nice neutral steering feel, and it turns into corners comfortably.”
“Compared to an ADV bike,” he continues, “I think it handles closer to the KTM 950 ADV S. It’s very capable off road and weighs about the same at 462 lb., with the plastic tank. There will be plenty of skeptics who will call bullshit on this, but watch Jamie Robinson of MotoGeo ride the bike in the Mojave Desert on the ‘Ghost Town’ episode online video. He shows how capable the bike is!”
Even though it’s been well-reviewed by competent riders, has grabbed trophies at bike shows, and been viewed by many eyeballs in custom motorcycle blogs, he’s still thinking of ways to improve his project. Like a modern-day Burt Munro, but obsessed with a Harley-Davidson Sportster instead of an Indian Scout, Carducci is constantly thinking of ways to get more performance from his machine. It continues to evolve a little every year.
For future projects, he’s been tinkering with the idea of building a bike around an S&S high-performance motor, using a chromoly frame. He’s even looked at Harley-Davidson’s new Street Rod model based on the liquid-cooled 750cc engine. Carducci figures the frame and engine are usable in a project similar to what he’s already done.
But for now, Carducci seems happy to stick with the Sportster platform. He’d like to get more people aboard, but he isn’t interested in manufacturing more and selling them (he’s only built two prototypes so far). At one point, he considered offering a conversion kit, selling customers the parts to build their own machines, but now he’d rather sell the manufacturing rights to an established aftermarket supplier, someone like Storz Performance.
If that happens, don’t expect the machine to be a budget-friendly build; even after buying the parts in bulk to lower costs, the SC3 would be pricey. But for now, if you want a V-twin Harley-Davidson-powered adventure bike, it’s the best option out there—unless you build your own, like Jim Carducci did. CarducciDualSport.com
Zac Kurylyk is a writer based in Saint John, New Brunswick, Canada. When he’s not pounding away on a keyboard, he’s exploring Atlantic Canada on and off road, looking for more adventures to share. Find more of his work at CanadaMotoGuide.com.