Ducati 900SS custom by Atom Bomb

By Wesley Reyneke | Rather Be Riding

With the new-wave custom scene continually evolving and diversifying, it’s becoming progressively more difficult to classify custom motorcycles. Even the mere mention of the term “café racer” is enough to send purists into a frenzy these days. It gets even more complicated when the donors are ’90s-model Ducatis—an emerging trend that we’re loving.

Who better to blur the lines than Clay Rathburn of Atom Bomb Custom Motorcycles? Clay’s a master craftsman whose work we’ve featured multiple times, and who seems to be able to turn his hand to any style of bike. His latest creation is this breathtaking Ducati 900SS-based café-racer-cum-streetfighter.

“I traded into a mostly stock 1996 900SS a couple summers ago,” says Clay. “The stock carbs were shot and it had a wiring issue. I put a set of Keihin FCR carbs on it, fixed the wiring, and rode it enough to totally fall in love with the way it made power.”

Unfortunately, Clay soon realized that the 900SS needed more work: “the stock suspension was shot, and I could feel the frame flexing.” On top of that he wasn’t too keen on its looks, so onto the bench it went.

“I guess this project was about building the right home for a fantastic engine, and (as usual) doing something I’ve never done before by building a proper sport bike.” Despite establishing his reputation with more classically-styled bikes, Clay does have some connections to motorcycle racing—Atom Bomb were responsible for the fuel tanks on Danny Eslick’s Daytona 200-winning Triumph 675. “I’ve always loved sport bikes, just never built one from the ground up.”

Clay’s original plan was to source a 999 frame to house the 900’s 2v mill—but, since he had a blueprint of the 999 frame, he decided to build one from scratch instead. Using “a calculated mix of tubing sizes and wall thicknesses,” he was also able to brace it better than a stock 999 frame. The suspension geometry is identical though, with the exception of a 23.5 degree neck angle—achieved by re-using the donor bike’s neck.

Since the 900SS was a personal project, the budget was limited—forcing Clay to mix and match suspension components. Up front are a set of Showa forks from a late-model Suzuki GSX-R, set in the 900SS triple trees “because they fit the GSX-R forks, and more importantly because the offset provided the correct trail numbers for the 23.5 degree neck.”

The GSX-R also supplied the Brembo monobloc radial brake calipers, matched to floating Brembo rotors. An Aprilia RSV front wheel was mounted up front, with a Ducati 999 rear wheel, swingarm and shock out back. Clay also fitted an Öhlins steering damper via Atom Bomb mounts.

Without any particular direction in mind, Clay set about fabricating all bodywork from aluminum—starting with the tail. “It’s fair to say the shape of the tail was 100% dictated by the 1098 tail light I bought for $20 on eBay. When I got it, it had a LOT more angles than I thought, but I paid for it so I built the entire tail around it.”

He then “played around” with shapes for the tank until he found something that fitted visually. Despite its small appearance, it carries 4.5 gallons of fuel. Other bespoke bits include the foot controls and the front fender brace, which holds a powder coated Ducati performance fender.

The engine wasn’t left untouched—with almost 30 hours spent on the heads alone before being put back together “with a lot of go fast fun parts”. The checklist reads like any sport-bike fan’s dream: in addition to the upgraded carbs there are Fast by Ferracci high compression pistons, ported and flowed heads and manifolds, CA Cycleworks heavy duty head studs and an Ignitech programmable ignition with CA Cycleworks coils.

Atom Bomb also lightened the flywheel and installed an aluminum clutch hub, basket and plates, along with a Yoyodyne clutch master cylinder and a heavily modified 1098 oil cooler. The modded engine now breathes out via a hand-made stainless steel exhaust system. “We haven’t dyno’d it yet but based on riding a lot of stock 900cc Ducatis, we’re making substantially more power everywhere in the rev range.”

After a few miles on the road to tune the carbs, Atom Bomb took the 900SS, now dubbed “Eleven”, straight to the track—where friend and experienced club racer Andrew Swenson put it through its paces. “The plan was to take it easy for the first session, adjust what we need to adjust, and ease into going fast. Andrew came around on the third lap of the first session wide open and dragging an elbow, and ended up riding four or five sessions where we had planned to do three.” Since the track test, Clay’s put about 300 street miles on the bike, and claims he’s “never ever had so much fun a motorcycle.”

Does this mean we can look forward to more jaw-dropping Ducatis from the Virginian workshop? “I learned a ton about the entire Ducati model lineup while I was building this thing, and of course had a bunch of ideas for the next one while we were putting the finishing touches on. So I’m beyond positive there will be more very trick air cooled Ducatis in Atom Bomb‘s future!”

Clay made a point of thanking the following people for their contributions: Andrew Swenson at Andrew Swenson Designs did the lettering, stripes and painted the timing belt covers and headlight. Shaun Stewart at Slingshot Cycles custom built all of the brake and clutch hoses. TPO Parts sent us some floating rotor buttons to make our front brakes work so much better, and CA Cycleworks helped us out with heavy duty head studs and ignition coils. Big thanks to everyone!!

Images by Anthony Hall.

BMW R nineT custom by UCC

After building bikes for nigh on 20 years, Unique Custom Cycles has a reputation most builders would die for. The Swedish company is known for its traditional chopper and drag racing builds, but its latest project—nicknamed The Stockholm Syndrome—is very different.

UCC’s Ronna Norén and Gordon Roth like a challenge, and a few weeks ago BMW Motorrad dropped one right into their laps. They were given just five weeks to revamp a BMW R nineT, to enter into the famous Norrtälje Custom Bike Show.

For 35 days, Norén and Roth barely slept. But as you can see, the result was worth it. ‘Stockholm Syndrome’ is a clean and rakish roadster, the naked cousin of Roland Sands’ faired Concept 90 bike. And despite the tight timeframe, this R nineT is rammed with high-end Swedish engineering.

The forks and triple trees are new, built in collaboration with Tolle Engineering. The brake system was designed with the help of ISR, and features radial 6-piston calipers grabbing 320 mm fully-floating disks. The ABS sensors are retained, and on the custom handlebars is an adjustable ISR master cylinder. Öhlins got into the act as well, providing a custom shock and steering damper that we’ll probably see in production soon.

The bike is also a showcase for UCC’s own fabrication skills. The frame has been cut and raked a few degrees, and fitted with inserts from Perka Nyström of Plebs Choppers—the legendary Swedish motorcycle club that includes BMW Motorrad head designer Ola Stenegärd amongst its members.

The super-sano tank is a cut and modified R nineT original, matched to a custom seat from Stitch Sweden and a hand-made rear subframe. The exhaust system is newly fabricated from stainless steel, hooked up to a Burns muffler, and even the oil cooler is a UCC custom part.

Despite the clean, classic looks and extensive modifications, all the R nineT electronics are retained. Norén and Roth spend a lot of time working with modern Harleys, so they are comfortable negotiating their way around ECUs and wiring looms.

‘Stockholm Syndrome’ was entered into the Custom Class of the Norrtälje show, which meant it had to be ridden to the event. “We had 96 km of tiny country roads to ride, and there were no incidents at all,” the UCC boys report. “The Custom Class is one of the biggest classes, so we were up against 45 to 50 bikes—mostly Harleys. We didn’t think we had a chance because of the Harley domination in that class, and some of the experienced Harley builders were judges. That’s how it works at this show, and we thought the judges would not see what we’d put into this build.”

UCC did not take the outright trophy, but came in second. Which for a modern-style café racer in a sea of choppers, is a win all the same. And the build got a tick from Ola Stenegärd too. “Very clean, very Swedish somehow. Beautiful proportions with a lot of trick trademark UCC details and technical solutions. The wheel combo and overall stance is one of the best I have seen.”

“At the show, we had nothing but positive reactions,” says UCC’s Ronna Norén. “The one comment we heard most was ‘I can imagine having one of these’.”

We could imagine that too.

Images © Jenny Jurnelius. Head over to the UCC website or Facebook page to keep track of new builds from Ronna Norén and Gordon Roth.

Top 5 2-stroke motorcycles

By Wesley Reyneke | Rather Be Riding

There’s nothing quite like the smell of two-stroke oil. Or the sound of a swarm of two-strokes hurtling down the track at full tilt. Then there’s that power band—a trait that earned some larger-capacity bikes the title of ‘widow maker’.

Whatever the reason, there’s a certain romanticism associated with two-stroke engines. They’ve powered some of the most legendary motorcycles of all time, dominating track and off-road racing. I’ll never forget the time my dad took me to Kyalami in ’92 to watch the likes of Wayne Rainey, Kevin Schwantz and Mick Doohan duke it out. (John Kocinski ended up winning that race.)

Sadly, modern emissions laws have seen a drastic decline in the use of two-strokes. There are ways to make them compliant but, as Kevin Cameron explains in this piece for Cycle World, few manufacturers are willing to invest in the R&D required. So most two-stroke engines are now found in scooters and dirt bikes.

So it was time we asked the question: is a vintage two-stroke a good choice for a custom build? After scouring the archives, the answer is a resounding yes. We decided to exclude restored and replica race-bikes, and focus instead on rare and exotic machines, and here are our top five picks.

Let us know in the comments if they inspire you to take up smoking.

Kawasaki H1 by Valtoron Kawasaki’s 498cc, triple-cylinder H1 was one of the first two-strokes to earn the ‘widow maker’ title. This one, a ’74 model dubbed La Bomba, was built by Spanish foundry Valtoron. The H1 was powerful enough in stock form, but it’s been boosted further with Wiseco high compression pistons, and reworked ports and expansion chamber—the result is 70 horses at the rear wheel.

Valtoron also braced and reinforced the H1’s notoriously wobbly frame, dropped the front end and upgraded the rear shocks to Koni items, connected to a Kawasaki GPz550 swingarm. All the bodywork was cast from recycled aluminum, finished with some bronze bits and a leather saddle. The headlight’s particularly quirky—it’s a Zundapp unit, ‘floating’ in a custom bracket. [More about this bike]

Photo by Kristina Fender.

SWM 320TL Trials Lorenzo Buratti wanted a bike for his 17-year-old daughter to learn to ride on that could double-up as a bike for ambling through the woods. So he refurbished this old SWM 320TL—an Italian-made motorcycle powered by a reliable 280cc Rotax engine. Buratti kept things simple – mounting the tank from an old Motobecane enduro bike and electing not to paint the engine or frame. (“I like the idea of a bike that carries signs of the times.”)

He polished the forks and painted the exhaust though, and trimmed and fitted a Kawasaki Z900 rear fender. The air filter’s protected by a tomato can, and most of the bike’s other parts were found at various swap meets. It’s a bike that didn’t cost Buratti much, or take him too long to build, but hits the mark with an effortless vintage charm. [More about this bike]

Suzuki GT550 “Honduki” by MotoHangar This ’75 GT550-powered custom from MotoHangar in Virginia is mental—and downright desirable. It’s a bit of a parts-bin special, but in the best way possible. The subframe is custom, the tail unit is from a Kawasaki GPZ and the expansion chambers are from a Kawasaki H1. There’s also a Honda headlight, a Suzuki SV650 swingarm and GSX-R forks and wheels. Naturally the air-cooled triple’s been bored out as well—to .50 over. Completed entirely in-house, including the paint and graphics, it’s straight out of the left field—but should make for an explosive ride. [More about this bike]

Ossa Copa ‘Grand Prix’ by CRD Café Racer Dreams keep popping up in our Top 5s. It’s understandable though—the Spanish garage has a cohesive and pared-back style that’s hard to ignore. This classically-styled 1979 Ossa Copa 250 proves just how versatile they are. The Copa is a lightweight single known for it’s unusually low mixture ratio—3.5% as opposed to Ossa’s usual 5%.

CRD rebuilt the motor, fitting a Mikuni 38 carb and a hand-made exhaust system. They also strengthened the frame, upgraded the forks and replaced the stock five-spoke wheels with 18” aluminum items. A race replica tank’s been fitted, paired with a Yamaha tail piece and custom seat, and finished in an eye-catching green and white scheme. [More about this bike]

Photo by Kristina Fender.

Yamaha RD350 by Analog A round-up of custom two-strokes wouldn’t be complete without a Yamaha RD350. This 1973-model was bought as an incomplete café-racer project, which sat around for a few years before its owner took it to Tony Prust of Analog Motorcycles to finish the work.

The biggest change Prust made was cutting the neck tube off so that he could graft on a Ducati S2R front end. For the wheels, he laced the original RD rear rim to the front hub, choosing a Yamaha TZ250 GP rim and hub at the rear, and replaced the stock rear drum brake with a disc.

Brembo rotors and calipers have been fitted all round—both linked to the right foot lever. The bars are super-clean, thanks to an internal throttle system and the lack of a front brake lever. A hydraulic clutch has been installed too, and the engine’s been treated to DG expansion chambers and Uni pod filters. The frame has been de-tabbed, and a custom leather and Alcantara seat fitted.

Kiel Sawusch of Crown Auto Body was responsible for the paint—a slick black and white scheme that reinforces just how clean and tight this build is. [More about this bike]

Photo by Timothy Prust.

Motorcycle resto: all together now

One of the delights of restoring a motorcycle is putting it all back together again. It’s like building a jigsaw—complete with the inevitable frustrations of getting certain bits to fit.

In this week’s Saturday Sessions clip, we return to E3 Motorcycles’ Brooklyn workshop to see the Honda CB550 return to life. It’s the shop bike of New York ad agency Woods Witt Dealy & Sons, and they’re looking forward to getting it back.

“Some parts of the rebuild process are rad and exciting,” says E3’s David Browning. “Like finding a stellar deal on a donor bike. Or UPS showing up with that new-old-stock tank you scored for a song online. Then there’s the other 90% of the process: The part most folks tend to leave out of the montage scenes. Which is what we’re doing this week.” And it looks captivating.

E3 have installed new OEM Honda 5.5mm fuel lines, overflow lines, and the air box assembly. There are no deviations from stock here, because the SOHC4s tend to run best with the original airbox and plenum components.

Next up is the advance and points assembly, closely followed by the battery and electronics trays and the wiring harness. Even if you’re not mechanically minded, it’s fascinating to watch.

E3 Motorcycles | Woods Witt Dealy & Sons | Previously: Part 6: Installing The Engine

Yamaha SR400 Yard Built by Benders

Brothers Christian and Raphael Bender had the kind of childhood most of us dream about. They started out messing around on dirt bikes near Germany’s picturesque Black Forest, and began rebuilding bikes to finance far-flung adventures in the dunes of the Sahara desert.

After a successful foray into the business world, the brothers have returned to their roots. Feeling that something was missing from their lives, they’ve set up Benders, a small workshop in Ettlingen. Their customs have a distinct enduro flavor, and caught the eye of Yamaha Europe. Hence this sharp-looking SR400, the latest addition to Yamaha’s ‘Yard Built’ program.

The Benders have a taste for simple, effective machines with real-world usability—like classic XT, SR and XS Yamahas, Triumphs and Betas. For their Yard Built bike, they’ve captured the vibe of the legendary XT in a modern package.

The idea was to keep the approach down to earth—which meant no cuts to the frame, practical functionality, and a starting point for bolt-on custom parts. Christian and Raphael had just four weeks to build this clean-looking SR400, nicknamed ‘Homage,’ but you’d never guess.

The forks have been extended, and another 30mm added at the back via custom shocks. Custom triple trees accommodate the new geometry and higher ride height, with Heidenau Klassik Enduro tires offering a little more bite on loose surfaces.

Other mods include enduro-style footpegs and foot controls, and chrome enduro bars for extra leverage at the helm. The shortened seat is a custom unit, allowing space for a small luggage rack.

Adding to the vintage enduro vibe are custom aluminum fenders, a custom bash guard for the engine, and new alloy side covers and clear-coated engine cases. Compact lights, instrumentation and number holders keep the look minimal and functional.

There’s a free-flowing custom exhaust too, hooked up to the stock lamda sensor. “The sound is still very SR, not too loud but giving a more intense ‘single’ note. The complete fuel injection system still works and makes it easy to perform the famous ‘one kick’ procedure when starting this lovely little bike.”

It’s all topped off with a vintage TT500-style paint job. Looks like fun, doesn’t it?

Images by Sven WDMYR at Wheels of Stil. Check out Christian and Raphael’s other classy builds on the Benders website. Or head over to our Google+ page for a high-res gallery.

Guzzi Nevada custom scrambler

The big money-spinner for Moto Guzzi these days is the ‘new’ V7 range. But although the V7 has put the Mandello Del Lario factory on a secure footing, the heart of the bike is nothing new. The iconic 750cc ‘small block’ engine design can be traced back to the mid-seventies.

The V7’s appeal largely comes from its retro styling, which has elevated it above two close cousins: the somewhat anodyne Breva and the cruiser-ish Nevada. Both are competent bikes, but have hardly set the motorcycling world alight. Which makes me wonder: has Moto Guzzi missed a trick by not building a scrambler variant?

When this delightful custom scrambler landed in my inbox, my suspicions were confirmed. Until recently, it was the personal ride of Officine Rossopuro founder Filippo Barbacane. It’s based on the Nevada platform, and it’s powered by the same small block engine you’ll find in a V7.

Massaging a Nevada into the scrambler style is tricky, but not beyond the capabilities of a competent builder like Barbacane. The rear end of the frame is new, as is the beguiling all-aluminum bodywork. The electrical system is now hidden in the tank, and the overall theme is one of simplification, from the controls on the new bars to the compact lighting.

There’s a custom two-into-one single air intake, with the filter projecting out of the side panel. The custom exhaust is also two-into-one, and despite running under the engine, suits the style of the bike perfectly. Barbacane designed the bike to be effective off-road, so he also upgraded the shocks to Bitubo items for better control.

Best of all, he’s cut the weight down to a mere 150 kg or so. Not quite motocross levels, but light enough to provide an entertaining ride. Especially when you factor in the renowned tractability of the Moto Guzzi small block V-twin.

I’m sold on the concept, and could see this machine parked next to the V7 in my own garage. Perhaps it’s time Moto Guzzi built an official V7 scrambler, to compete with Triumph’s popular offering?

The new Hesketh motorcycle

Received wisdom says that starting up a new restaurant carries more risk than any other type of business venture: Apparently some 60% of eateries close within five years.

But I suspect that received wisdom is wrong. I reckon it’s even more difficult to launch a low-volume motorcycle company. The financial travails of the smaller Italian marques are well known, and in more recent years, aspersions have been cast on the ability of Norton to (literally) deliver the goods.

That makes Paul Sleeman, the owner and chief engineer of the reborn Hesketh Motorcycles brand, a brave man. But he’s created a very interesting bike with a mix of tried-and-trusted hardware, and may just avoid the pitfalls of those who have gone before him.

The new ‘24’ harks back to the days of James Hunt’s adventures in the Hesketh F1 car, and has little connection to the Hesketh motorcycles of the 1980s.

The spec is good: the heart of the machine is a 1950cc air-cooled S&S X-wedge engine hooked up to a Baker transmission. The engine is popular with custom builders in the US, and somewhat bizarrely, is also employed by the British car company Morgan to power its retro-styled three-wheelers.

No weight figures are given, but with 125 hp and 144 pound-feet of low-down torque on tap, performance will be brisk. As an added bonus, the motor has been tuned by Harris Performance, who can modify its characteristics to suit an owner’s preferences.

The suspension comes from Öhlins, with Beringer supplying the brake system. The seat is covered with Italian nappa leather, and is the work of McLaren upholsterer d:class automotive.

The 24 is a limited edition, and you can probably guess how many will be made. In the UK the price is £35,000 (US$60,000) and three bikes have already been sold. There are orders for eight more and the machine is approved for registration in the USA.

Tempted? Head over to the Hesketh Motorcycles website for more details.

With thanks to Tom Stewart.