Niko Bakker Honda CBX1000

Nico Bakker is the welding-torch wizard of chassis-builders – the go-to guy to consult when a high-class piece of hardware is required.

So when 36-year-old Dutch systems analyst Maurice de Back wanted to cement his passion for the classic-era Honda CBX1000/6 by creating a modern-day six-cylinder streetfighter, there was only one man to approach.

The Bakker CBX Orange Blossom special is the result – a unique tangerine dream-come-true that’s an inspiring blend of old and new, combining Bakker’s timeless chassis skills with an iconic powerplant from Honda.

When it was launched on an unbelieving bike world back at the end of 1977, the Honda CBX represented a ‘beat that’ throw of the gauntlet by a company traditionally associated with leading-edge four-stroke engineering.

Indeed, its air-cooled straight-six 24-valve 1047cc engine not only represented an imposing visual statement, but by producing 105hp (77kW) at 9000rpm it could propel an unfaired bike weighing a hefty 253kg to a top speed of 225km/h.

The 41,200 CBX sixes built in four versions from 1978 to 1983 proved bulletproof as well as imposing, with the CBX1000/6 developing cult status for a core of enthusiasts.

The first time de Back saw a CBX was 25 years ago, and he was instantly smitten.

“My whole love affair started when I was 10 years old,” he recalls. “I was with my mum in town, and I saw a CBX in front of a traffic light with the engine burbling away on idle.

“It had a six-into-one exhaust, and I couldn’t wait to hear it accelerate. The sound was just incredible – it made my hair stand on end and my skin shiver, and I knew at once I needed to have one of those bikes, one day.”

Years on, in 1999, de Back made that dream come true with the acquisition of one of the final versions of the Honda six, an ’83-model CBX with a bulky half-fairing and Pro-Link monoshock rear suspension.

“I thought it was really ugly to look at, but it was all I could afford, and the engine was okay even if it was smoking because of a seized oil ring,” he says.

“I ran it for a while, and then in 2000 I decided to have Ruud de Groot rebuild it – he’s quite famous in Holland, because he worked for 10 years with Honda Netherlands. He rebuilt the engine with new parts, so then I had a new motor but an old, very ugly chassis. So that’s when I went to see Nico Bakker.

“I knew all the stories about how Nico Bakker made the chassis for Jack Middelburg’s 500GP bike and how Jack beat the Japanese with it at Assen in 1980, so I expected Nico to be a bit unapproachable,” says de Back.

“But I was really in love with the CBX, and after I visited Nico a couple of times and discussed it with him it was obvious he was the perfect person to help me create a modern CBX streetfighter.”

Bakker had already built a handful of CBX-engined streetbikes back in 1986 replicating an endurance racer style, but de Back wanted something different.

“I didn’t want a retro model like one of those – I wanted a modern bike with a comfortable seat, and the engine had to be a part of the design, too,” says de Back. “That’s why I painted it black, so it was integrated with the frame to make it look smaller.”

Imposing but not encumbering, the Bakker CBX has plenty of presence – a visual impression that wasn’t let down when I rode it. It’s not too tall, so it was easy to sling a leg over, and thanks to the slim 20-litre aluminium fuel tank it rather surprisingly doesn’t seem too bulky when on the move.

“The chassis isn’t the lightest,” says Bakker. “But it’s made from 4130 chrome-moly tube with a 38mm diameter, so it’s plenty stiff enough for a heavy engine that weights 102kg with carbs.

“I based the geometry on the frame I made for the Grizzly streetfighter with the GSX-R1000 engine.”
The finished product has a longish 1535mm wheelbase (quite rangy compared to the stock CBX’s 1498mm), but that’s compensated for by tighter steering geometry than the original, with the 43mm WP upside-down fork set at a 24-degree rake with 98mm of trail.

What’s most unusual is the far forward 57/43 per cent weight bias delivered by the inclined engine package and the long wheelbase.

“I wanted to make sure the front wheel had lots of grip, and that the wide engine is mounted high enough to give enough ground clearance,” says Bakker.

This isn’t the kind of bike where you’re looking to drag your knees and/or the cases through corners. Instead, it’s a package to turn, point and squirt, while revelling in the waves of syrupy torque and liquid horsepower, which is still plenty impressive for a 33-year-old engine design.

Long-distance trips, such as the 700km day ride de Back took to the season-ending MotoGP at Valencia, Spain, aren’t too much of a chore on the Bakker CBX. The seat is quite comfortable (by streetfighter standards), although the upright riding position isn’t conducive to touring speeds of 150km/h-plus.

The lovely liquid-feeling engine pulls cleanly away from the low 800rpm idle without a trace of transmission snatch all the way to the 8500rpm power peak, where 104hp (76kW) is delivered at the back wheel.

Mark Tronics, the Dutch tuning shop run by former Ten Kate race engineer Maarten Fijlstra, supplied the only non-standard part on the Bakker CBX’s mechanical package, a specially developed six-cylinder digital ignition.

Not only does this resolve the problem of the lack of availability of stock CBX Honda CDIs, but the digital replacement provides more power, greater torque and a sharper throttle response with the same stock 28mm Keihin CV carbs.

This boosted performance is delivered against the musical backdrop of the custom-made six-into-two Laser exhaust’s twin carbon cans, matched to the sextet of Honda headers.

The half-fairing is the top half of a 2004-model Honda CBR600RR, complete with stock Honda headlights and a rectangular dash housing French-made Mode 7 digital instruments. The Bakker CBX’s archaic 1980s’ switchgear is at odds with this digital Y2K kit – it sure makes you realise how the world has moved on in the past quarter-century.

Late-model Honda Fireblade brakes are fitted, but the result is surprisingly disappointing, with not a lot of bite from the massive 330mm front discs and their six-piston Nissin calipers. I know from experience these brakes will stop a truck, so I can only assume the wrong pads have been fitted. Pity, as the rest of the bike is dynamically quite satisfying in real world riding conditions, as well as great to look at.

What we have here is essentially a high-class special, built around a Bakker frame kit, but finished off by an enthusiastic owner rather than finely honed by Bakker himself.

“I’m totally in love with it – even if it cost me 10 years of my life and 35,000 Euros to create it,” says de Back. “But it’s a unique bike made just the way I wanted it to be, to my specification and taste, but with Nico’s skills.”

WHO IS NIKO BAKKER?
This year Dutch chassis guru Nico Bakker celebrates his 35th year in business. He’s arguably Europe’s leading practitioner in the black art of motorcycle frame building, and can boast a list of design features that reads like a textbook of modern-day chassis technology.

The genial 61-year-old Dutchman was the first to fit monoshock rear suspension to a GP racebike; the first to use a rising-rate link on the rear end of any motorcycle; the first to employ upside-down forks for street use; the first to fit a single-sided rear swingarm to a four-cylinder streetbike (some years before Honda did so on the RC30); the first to offer a four-cylinder hub-centre streetbike for sale (ditto, before Bimota); the first to build a shaft-drive motorcycle with a deltabox-type twin-spar aluminium frame; and the first to design, manufacture and fit a six-piston brake caliper to a motorcycle of any kind.

Bakker has designed and built motorcycle frames for engines from 50-1100cc; from GP-winning racers to avant-garde streetbikes; from two-strokes to four-strokes to even a rocket-powered motorcycle (World Drag Racing Champion Henk Vink’s record-breaking projectile); has worked with factories from BMW to Yamaha in developing new street models; and has even been paid the compliment of having his chassis designs copied by Honda on its works GP racers. Nico Bakker is without question the frame builders’ frame builder.

Yet Nico is entirely self-trained, and got into chassis building almost by accident. In 1976 he gave up his job as a car mechanic to move into the same workshop he still has today (known as De Framebakkerij, or ‘frame bakery’, as a pun on his name!).

“I originally planned to stop racing for a year to get it off the ground,” says Bakker, “but that was 30 years ago, and I haven’t raced again since!”

The first customer Bakker race frames were inevitably for the TZ250/350 Yamahas then dominating GP race grids, but whose twin-shock chassis design and uncertain handling left room for improvement.

Nico’s first customers in 1976 read like a Who’s Who of mid-’70s GP racing: Franco Uncini, Takazumi Katayama, Boet van Dulmen, Johnny Cecotto, Wil Hartog, Dieter Braun and many others all began racing Bakker-Yamahas.

This gave the new Dutch chassis builder instant credibility – for the simple reason that his designs worked.

“I was the first to fit monoshock rear suspension to a road racer, which gave a big improvement in chassis behaviour, together with the better weight distribution and extra stiffness my frames had compared to the Japanese ones,” says Nico.

“Eventually, Yamaha sent its factory rider Sadao Asami to buy frames from me that Yamaha could study and copy. In fact, he became a good customer.”

This led to a direct relationship with Yamaha through its European HQ in Amsterdam, for whom Bakker designed a special frame for the three-cylinder 350 triple ridden to the world title by Katayama in 1977.

Nico Bakker’s growing reputation didn’t take long to reach Italy, thanks to satisfied customer Franco Uncini, who by 1977 had joined the world championship-wining 250/350 works Harley-Davidson.

Uncini was unhappy with the handling of his 250 H-D’s Italian chassis, so just three weeks before the 1977 Dutch TT at Assen he commissioned Nico to build a new frame. When the Italian team discovered what Uncini had done they forbade him to race the result, but Uncini ignored instructions and rode the brand new bike at Assen – and won!

In the early ’80s Nico also turned his attention to the big 1000cc four-stroke category, building frames for almost every engine design, including all the in-line fours and the V-four Honda VF1000.

To promote his chassis, he started his own World Endurance race team, winning the 1984 Le Mans 24 Hours with a Bakker-Suzuki against all the top Japanese factory teams.

Bakker Framegebouw today concentrates on building custom designs to special order, and especially his popular GSX-R1000-based Grizzly streetfighter, as well as development projects for manufacturers like BMW.

For Yamaha Bakker created an FZ750-powered prototype nakedbike in the 1980s with a tubular steel frame, which finally evolved into the Diversion.

He also developed his own avant-garde chassis design, the radical, hub-centre QCS launched in 1987. This was powered by a range of engines, notably the FZR1000 Yamaha donk.

“I designed it as an experiment, to see if we could improve on the handling of the latest upside-down forks,” he says, “and I was honestly surprised how much better the QCS was.

“But bike riders are very conservative, and the fact I’ve only sold 14 QCS roadsters in 18 years underlines that.”

With literally thousands of different frame designs under his belt, Bakker has more experience than any other chassis designer working anywhere in the world – yet he remains convinced that frame-building is more of an art than a science.

“You just develop a feel for what’s right and what’s wrong,” he says, “and though I use CAD equipment to design the frames, and CNC machines to make a large part of them, at the end of the day these are hand-built creations that reflect our years of experience.

“Even after 30 years, I’m still learning.”

TECHNOLOGICAL MARVEL
When it was launched at the end of 1977, the Honda CBX1000 represented a technological statement by the company most traditionally associated with leading-edge four-stroke engineering.

Indeed, the CBX/6’s wide 24-valve, 1047cc engine with central chain-drive for the two camshafts also represented an imposing visual statement.

To add further lustre, it was designed by Honda’s high priest of grand prix engine technology, Soichiro Irimajiri, who in the 1960s had been responsible for conceiving such iconic race bikes as the world title-winning 250/350 sixes and five-cylinder 125.

Indeed, it’s not hard to imagine it as a project very close to the heart of company founder Soichiro Honda, then still very much a part of his company’s two-wheeled design strategy.

The 41,200 CBX sixes built in four versions from 1978 to 1983 proved bulletproof as well as imposing. Yet, for all its technical charisma and imposing appearance, the CBX didn’t really sell in the numbers Honda must surely have hoped for – neither in its original CBX-Z performance roadster guise, nor the American-market CBX-A version.

The US ‘A’ version had the same twin-shock frame but with higher handlebars, footrests further forward, a more robust drive-train with wider rear wheel, and a slightly detuned engine to comply with new US legislation limiting motorcycle engine performance to below 73.6kW (100hp) “in the interests of safety”.

Honda responded to the disappointing sales of the Z and A by repositioning the model into the Sport Touring sector with the 1981 debut of the CBX-B, which besides a cosmetic makeover with the addition of a half-fairing, featured a revised chassis with Pro-Link monoshock rear suspension.

It also had a beefier 39mm fork raked out two degrees to a rangy 29.5 degrees, uprated ventilated brakes, and a hefty increase in weight to 270kg.

Sadly for Honda this didn’t send the cash register ringing either, despite a final 1982 revamp under the CBX-C label.

Production was duly shut down – but now, 33 years on, the CBX is a prized collector’s item all around the world in any of its versions.

SPECIFICATIONS BAKKER HONDA CBX1000/6
ENGINE
Type: Air-cooled, DOHC, 24-valve, four-stroke, in-line six-cylinder
Capacity: 1047cc
Bore x stroke: 64.5 x 53.4mm
Compression ratio: 9.3:1
Fuel system: 6 x 28mm Keihin CV carburettors

TRANSMISSION
Type: Five-speed
Final drive: Chain

CHASSIS AND RUNNING GEAR
Frame type: Chrome-moly tubular steel twin-spar
Front suspension: 43mm WP inverted telescopic fork, fully adjustable
Rear suspension: Chrome-moly tubular steel swingarm with full-floater rising-rate link and
WP monoshock, fully adjustable
Front brake: Twin 330mm Nissin steel discs with six-piston Nissin calipers
Rear brake: Single 280mm Nissin steel disc with twin-piston Nissin caliper

DIMENSIONS AND CAPACITIES
Weight: 225kg (with oil, no fuel)
Seat height: N/A
Fuel capacity: 20lt

PERFORMANCE
Measured power: 104hp (76.5Kw) at 8500rpm
Measured torque: 90.2Nm at 6500rpm
Estimated top speed: Over 220km/h

OTHER STUFF
Year of construction: 2005
Owner: Maurice de Back, Marbella, Spain

Story courtesy of Motorcycle Trader.