1980-1982 Honda CB900C — The Factory Custom

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The Honda CB900C was praised for its power delivery, lack of vibration and straight-line performance.
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The Yamaha XS1100 Special was praised for instant power and called "a socially acceptable outlaw bike."
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The Suzuki GS1100GL was "as simple as a stone ax," and testers found little to criticize.

Honda CB900C
Claimed power: 83hp @ 8,500rpm
Top speed: 132mph
Engine: 902cc air-cooled DOHC 16-valve inline four
Weight: 588lb (wet)
Price then/now: $3,349 (1980)/$1,500-$2,500 

The term Factory Custom may be an oxymoron, but the 1980 Honda CB900C was Honda’s early attempt at blending sporting performance with cruiser credibility and touring capability. Did it succeed? Or was it just trying to please all the people all the time?

Around 1980, the full-size motorcycle market began splintering into numerous niches, including the Factory Custom. Seats grew steps, bars pulled back, footpegs inched forward, and clean drive shafts replaced messy chains. No doubt mindful that its game-changing V4s were in the pipeline, Honda stretched its trusty 4-valve inline 750cc to 900cc, then laid back its ergonomics to take on Suzuki’s cruiser GS850/1100GL and Yamaha’s similarly-themed XS1100 Special.

Essentially, Honda hijacked the engine from its Euro-spec CB900F to power the CB900C. The air-cooled, 16-valve double overhead cam with pent-roof combustion chambers was fed by four 32mm Keihin carburetors. A single-piece forged crankshaft drove a jackshaft via a Hy-Vo chain, with gear drive from the jackshaft to the clutch and 5-speed tranny. Shaft drive was de rigueur in the custom class, so to keep development costs down Honda borrowed the final drive unit from the GL1100 to use on the 900C. There was, however, one minor problem using the GL unit: the CB900’s tranny output was on the bike’s left side, and the GL1100’s shaft was on the right.

Honda’s solution was a crossover shaft — actually, two shafts incorporating two pairs of gears. This gave the CB900C a 2-speed “Select Range” secondary transmission sitting in its own transfer case, complete with its own trochoidal oil pump for lubrication. And while it wasn’t as complicated as it sounds, it wasn’t exactly simple. Cycle magazine counted “20 gears, six shafts, a dozen bearings, three torque cushions, a U-joint and assorted couplings employed in making the crank/rear wheel connection.”

The 2-speed transfer case meant 10 forward gears, giving CB900C riders incredible flexibility in gearing. It also went a long way toward the bike’s reasonable fuel economy. Kept in “high” range, reports of 50mpg were common. That said, left in “low” range and ridden with a heavy right hand the CB900C would return as little as 30mpg.

Yet the multitude of driveline components allowed generous driveline lash, which, combined with lean EPA-mandated carburetion, made for herky-jerky throttle transitions “the like of which you won’t find in any other motorcycle presently in production,” Cycle said. The extra transmission case also stretched the frame, and thus lengthened the wheelbase to a Harley-esque 62 inches — even using a short swingarm. This latter item introduced its own problems, causing noticeable torque jacking under acceleration and a lack of rear end traction under braking, chirping the rear tire. And the C-bike weighed in at nearly 590 pounds ready to ride, making it just about the heaviest machine in its class.

In most other respects, though, the 900C worked really well. Testers praised its electric-motor-like power delivery; lack of vibration (the engine was rubber-mounted); straight-line performance (less than 12.5 seconds at almost 110mph in the quarter mile — on  par with the XS11 and GS11); adjustable air-assisted suspension (also derived from the GL1100); and even its handling — in spite of a lazy 29-degree steering angle and squirmy 16-inch rear tire. Comfort was good (though the stepped seat trapped the rider in one position), brakes powerful and resistant to fade, and the 2-speed tranny reduced engine speed by a useful 500rpm at highway cruising speeds — and fuel consumption by as much as 16 percent if left in high. Even so, Cycle Guide concluded the extra five gears “bordered on the redundant” and a similar result “could easily have been accomplished with a 6-speed transmission.”

Built to Honda’s typically high standards, CB900Cs could pile on the miles. The 2-speed transfer case doesn’t appear to have any negative impact on reliability, and like other Honda fours the 900C had few major problem areas. But what really baffled testers was how to classify the CB900C. Was it a cruiser, a tourer or a new type of sport bike?

Though intended to appeal to American buyers, the custom styling left Cycle Guide testers cold. One called it the “King Kong Kompromise Kruiser,” while another considered it a dinosaur and hoped its inevitable extinction would “mark a return to a more sensible line of motorcycles where sheer size is not a prime factor.” A third thought it had been “dressed by committee.”

Ultimately, it was a bike in search of a market, and while briefly popular, it was dropped after just three years in Honda’s lineup. It’s perhaps ironic to note that the CB900C, a decidedly large bike when introduced, looks like a featherweight alongside today’s gargantuan boulevard bikes. Maybe it was just 30 years ahead of its time. 

Retro rivals to the Honda CB900C

Yamaha XS1100 Special
Years produced: 1979-1981
Claimed power: 95hp @ 8,500rpm/128mph
Engine: 1,102cc air-cooled DOHC inline four
Wet: 590lb (wet)
Price then: $3,699 (1979) 

Dubbed the “non-chopper chopper” by Cycle magazine, the XS11 Special came about from Yamaha’s own research that showed a growing market for a “mild lean-back” riding position. The result was Yamaha’s 1979 “custom” version of the 1978 XS1100 street bike, with stepped seat, pullback bars and a 16-inch rear wheel. The shorter gearing resulting from the smaller rear tire compensated for power-robbing EPA-mandated carburetion, keeping the Special’s standing quarter-mile time similar to the 1978 plain Jane version at less than 12 seconds at just faster than 113mph, the quickest of the three customs here.

Derived from Yamaha’s 850 triple (and sharing its 71.5mm x 68.6mm cylinder dimension), the 11’s engine was neoprene mounted in a double downtube frame. The crank drove its 5-speed transmission by Hy-Vo chain to a jackshaft, with spur and bevel gear shaft final drive. The 8-valve head breathed through four 34mm Mikuni CV carbs, fired by an unusual inductive ignition system with both mechanical and vacuum advance/retard.

Testers praised the big engine’s instant power, “like some runaway hydroelectric facility,” Cycle Guide said. And while they disliked the custom styling and “ridiculous” handlebar, most enjoyed the lazier riding position. The suspension was lacking and the Special tracked uncertainly on uneven surfaces, but Cycle Guide called it “an amazingly pleasant, admirably competent motorcycle. A socially acceptable outlaw bike; Butch Cassidy’s town mount, if you will.”

Suzuki GS1100GL
Years produced: 1982-1984
Claimed power: 94hp @ 8,000rpm/128mph
Engine: 1,074cc air-cooled DOHC inline four
Weight: 545lb (wet)
Price then: $4,199 (1982) 

While Honda’s solution for a shaft-drive cruiser involved novel and complex engineering, the GS1100GL by comparison was as simple as a stone ax. And while extrapolated from the tried and tested 850G and 1000G shafties, the 1100 actually shared few of their components. Differences in specification included electronic ignition, bigger bore and stroke, revised camshafts and larger 34mm Mikunis. The 8-valve 1100 filled touring duties, while all-out performance was the province of the new 16-valve GSX1100.

An evolution of the earlier GS1000L/GL, the 1100GL adhered to popular cruiser styling themes like stepped seats, pullback bars and small 16-inch rear wheel. The GS1100GL followed traditional Suzuki design, with a built-up crankshaft using roller bearings, and drive to the 5-speed tranny by helical gears. Output from the transmission fed a left-side shaft drive via bevel gears. Buyers who didn’t like cruisers could opt for the slightly more sporting G model, which maintained relatively conservative styling.

Motor Cycle News found little to criticize in the 1982 GS1100GL, except a patch of vibration that blurred the mirrors around 70mph and a tendency for the bike to weave at high speeds — which occurred regardless of suspension settings. But the end of the line was close for Suzuki’s bulletproof 8-valve touring fours. The new kid was already on the block in the form of the chopper-esque, chain-drive, 16-valve GS1100L. MC

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