Honda CB1100F Bol D'or

Overview

Shortly after its debut, the 1983 CB1100F earned a reputation as one of motorcycling's true superpowers — easily the most potent air-cooled inline-four Honda's ever built. This was Honda's first 1100cc superbike. Its arrival remains a benchmark for Honda in the evolution of the high-performance motorcycle.

Building on lessons learned from more than two decades of racing, Honda engineers created the 108-hp heart of the CB1100F. And as good as the rest of the motorcycle was, that engine made it a masterpiece. In Motorcyclist magazine's December 1982 road test, the 1100 turned an 11.38-second, 118.5-mph quarter mile. Then, during Motorcyclist's 24-hour endurance test, the 1100 covered 1,801 trouble-free miles around Willow Springs Raceway. That shattered the magazine's previous 24-hour record of 1,690 miles, set in 1981 by Honda's CB900F.

On the street, the magazine's testers discovered the bike's stunning low-end power. Throttle response was exemplary, thanks to the four constant-velocity carburetors equipped with an accelerator pump that kept throttle response very crisp.

In the chassis department, a new box-section swingarm pivoted on needle bearings. Working in concert with the steel-tube frame and a 39mm, air-adjustable fork, it helped deliver amazing stability and cornering. Motorcyclist later wrote, "And handle it does... nearly ideally. Bending the bike over into a turn requires very little effort at the handlebar. And it will stay there with no additional input from the rider." After factoring in the adjustable rear suspension and TRAC anti-dive control, they concluded, "Honda has won the Superbike Game hands down. The CB1100F is the best superbike Motorcyclist has tested."

Road Test Cycle 1983

Despite the CB900F, Honda showrooms haven't recently had a parking space for high-kinetic Superbikes. The 900F, though a superb backroad athlete, has lacked the muscle to punch its way into the brawling arena of the low-elevens.

Imagine the options facing Honda designers setting out to make a 1983 challenger. One choice was to build a completely new machine, based on V-four concepts. Honda did this in the 750 class—the VF750F Interceptor—and it's clear that at some point a full-liter model is easily possible. Honda had another option, one that was expedient, cost-effective and obvious—integrate parts from the European

Honda CB1100R (See Cycle, November 1982) into the American CB900F. Not all the parts, you understand, because the R-model's clip-on' handlebars and full-race seating and fairing would guarantee high visibility but next to no sales. The prosperous 900 F-type, however, might grow ever more successful in the United States with 1100A engine armament.

Honda took the second course. The 1100F rips down the drag strip at an 11.10-second crack, far under the 900F's 12.02 effort. Here's another ,figure that might make your wallet glow green. The 1100 tags out at $3698, only $200 more than last year's 900F and easily less than any other 1983 Superbike competitor. Honda's 1100F didn't get routed through the Product

Cheapening Department on its way to final assembly either. For your $200, the 1100 gives you cast wheels with tubeless tires, the TRAC anti-dive system, and enough suspension adjusting knobs to make your wrists ache.

If you're switching over from a CB900F, you'll notice that the 1100's seat is about one-half inch lower. That's the result of a one-inch reduction in wheel sizes, from 19 to 18 inches in front, 18 to 17 in the rear. One thing you won't notice is the 1100F's additional 8.5 pounds.

The 1100 lunges into traffic with a snap the 900 never had, a start that can set your eyeballs on full-open. As you accelerate onto the Interstate, first gear takes you to 57 mph at redline and second gear clears 80 mph. Once the tach zips clear of 7000 rpm, things  blur. Like other big-inchers, the 1100F has power that builds predictably. You never feel out of control; it's just that at almost any point you care to pick, there's a lot of power.

Stiffer springs make the 1100's clutch action a little heavier than the 900's. The clutch works fine for everyday street use—unless your idea of everyday use includes drag-stripstyle launches: revving the engine and slipping the clutch. Those starts turn the clutch lever into an on/off switch—the clutch becomes grabby.

At the drag strip we gave up trying to modulate the clutch during high-rpm launches; above 4000 rpm clutch-slip was impossible to control. We obtained the best launches by holding the revs at 4000 and quickly engaging the clutch.

Our test bike's shifting was less balky than that of earlier 750/900 series Hondas we'd ridden: although the gears engage with a clunk, the shift mechanism controls the cogs better. There is some gear-hopping and missed shifts, but less than before. Honda did not change the shifting mechanism from last year's; our unit was just a good specimen.

With suspension dialed into the softest settings, the 1100 gives a taut, well-controlled highway ride. Jack the suspension's settings up, find your favorite curvy road, and you'll discover that the 1100 lost none of the 900's backroad prowess. It's stable, forgiving and accommodating. Although the 1100's steering is a tad slower and heavier than the feather-touch '900F's, it still is effortless. You probably wouldn't notice any difference unless you rode the 900 and 1100 back to back.

The 1100F never wriggles, even over fast, choppy curves. Its front tire stays planted when you're riding hard out of corners. The footrests touch down barely sooner than the 900's, though there's plenty of ground clearance between earth and Major Metal. Only at lean angles we consider hazardous to street riding does the 1100 begin to drag—the sidestand on the left and the pipes and brake pedal on the right.

The Honda steers remarkably well for an 1100; you can flick it from side to side easily, even with the brakes on. The whole bike seems tighter than Suzuki's GS1100E. Particularly, the front end feels solid and doesn't wriggle in turns that cause the Suzuki to wallow. Sometimes, though, the suspension responds too slowly over closely spaced bumps, allowing the tires to hop.

The tires are very good; they have excellent feel and won't slide without warning. At Mach-two cornering speeds, speeds used by 99th percentile riders, the tires do drift a bit, slipping sideways and using up roadway. At these speeds it’s difficult to hold the bike exactly where you want it, but the bikes steering is so good that you simply tug the bars a little and make the in-corner correction. After hard riding, the rebound damping on our machine's shocks became limp and needed adjustment.

Only driveline lash, however, really detracts from hard, high-speed riding; the power hesitates at the first twist of throttle and then "hooks up" abrupty. Once the power cuts in, a healthy dose of throttle will ease the rear end out of the corner effortlessly. The driveline lash makes backshifting crucial during hard—very hard – braking. The combination of the 1100's light flywheel action, less than perfect shifting action, driveline snatch and the massive weight transfer during heavy braking combine to make the machine rear-traction sensitive. Catch a sloppy downshift and the rear tire breaks loose and chatters. Diving into corners this way makes any normal bike feel as though it's toppling into a precarious situation. Here again, thanks to its docile nature, the CB forgives such clumsiness and reciprocates with a predictable responsiveness.

If the handlebars don't suit you, you can vary the bars' handgrip positions about two inches, fore and aft. The bar height suited all the Cycle staffers and the range of adjustability satisfied everyone—a first. The system allows infinitely small variations and, most important, a useful range. At the bars' most rearward position, the grips angle back severely, positioning the rider's wrists awkWardly and decreasing leverage. At the foremost position, they flatten out to almost a straight-pipe configuration. Despite the increase in leverage, few testers found this position comfortable. Between the extremes, you should be able to find a good grip location.

planes. The peg location is as low and as far forward as is functionally acceptable; one six-footer wanted the pegs positioned the way the Sport Control Kit sets them—an inch or two back. Overall, however, the footpeg location provided fairly comfortable cruising for everyone, even on all-day rides.

During those long rides, the 1100F seat, firmer than the 900's, is still comfortable. But the engine's vibration may annoy some riders. The 1100 buzzes a little more than the 900 under 3500 rpm, and the big-incher passes through pockets of mild vibration on its way to redline. Around 55 mph in fifth gear, the bars and pegs buzz; this smoothes out completely around 60 mph.

The power unit underwent three major changes for 1983: more cubic inches, increased compression and extended cam lifts and openings. The true displacement is 1062cc or 64.8 cubic inches. That's just 160cc-9.8 cubic inches—larger than last year. The new 70mm pistons' higher domes bump compression from 8.8 to 9.7:1. (Recommended fuel type is 94 RON.) The cylinder head remains basically unchanged, retaining the same port shapes and valve sizes. Cam profiles now lift the valves 'to a maximum of 9.0mm, up 0.5mm on intake and 1.0mm on exhaust. Intake and exhaust duration have been extended five degrees each, producing 230 degrees duration and 25 degrees overlap—European CB1100R valve timing specifications. The 1100F has 33mm carburetors, one millimeter larger than the 900's.

Downstairs, the crankcase has larger spigot holes to accept the cylinder's bigger liners, though the crankshaft assembly is unchanged. To help the transmission withstand the extra punch, Honda gave the mainshaft a new heat-treating process and widened fifth gear 1.4mm. Engineers chose a twin-gear clutch hub to reduce noise and backlash. This system uses two gears side by side, one a tooth smaller than the other. The last driveline change is a smaller rear wheel sprocket, down two teeth to a 5.04:1 ratio. In addition, a bigger oil cooler, now eight-pass instead of four, doubles cooler potential.

Honda placed this powerplant in a modified CB900F frame, rubber mounted as before. (The CB1100R has its engine bolted rigidly in the frame.) The engineers moved the entire steering head back 10mm, and lengthened the steering stem 21mm. Head angle is 28.5 degrees (one degree more than the 900F's); trail is increased 10mm over the CB900F's. The net result of these changes leaves the front wheel's relationship to the engine unchanged from the 900F's. At the rear, the all-new box-section swing arm, which pivots on needle bearings, extends the wheelbase 10mm and places slightly more weight on the front wheel.

Though the new fork still sports 39mm tubes, it carries a three-way rebound damping adjuster at the top of each leg, as well as a cross-linked air fitting on the right side. The rear shock absorbers have new hand-adjustable three-way rebound damping rings at the top. (Adjusting the 900's shocks requires a tool.) The two-way compression damping also has fingertip adjustment. Almost any rider will find a satisfactory suspension setup for his kind of riding—with one exception: the lowest settings may be a tad too firm for riders under 140 pounds who want an Aspencade-like ride.

Increased slightly, the fork spring rates now follow current Honda practice—springing requires less air pressure. High air pressures increase seal pressure against the fork leg; reducing pressure decreases stiction and improves ride. Although sound in theory, the changes produced a firmer ride than that of last year's CB900F.

A built-in fork brace connects the lower sliders, which feature Honda's TRAC system. We like the TRAC and value its four-way adjustability for tuning the anti-dive effect. The fork brace completely eliminates flex between the handlebars and wheel.

The CB's six-spoke cast aluminum wheels have wide hubs that extend outward, allowing the use of flat disc brake rotors, which, according to Honda spokesmen, resist warping better than one-piece dished units. Initially, the semi-metallic brake pads seemed to give less braking force than the organic-compound pads used in 1982. As the pads bedded, however, the brakes gained stopping power. Metallic-compound pads generally offer fairly consistent wet and dry braking. In heavy rains, sintered metallic pads can directly cut the film of water that collects between the pad and disc, minimizing the braking delay characteristic of organic pads. For the record, we were unable to test the CB1100's brakes in heavy rain.

Except for color scheme, the CB's greatest visual change is the new fairing. This cowling shields the rider's lower torso: the windblast hits about mid-shoulder, not high enough to cause wind noise at the base of the rider's helmet. Although it offers little protection, it does provide a nice mounting place for the rectangular quartz halogen headlamp and the cleanly laid-out instruments. No video-game readouts here, just basic information. A small hood cuts glare on the dials. Here's an electronic footnote—a transistorized turn-signal relay replaces the mechanical unit of yore.

Other cosmetic changes include wraparound lenses on the new rectangular turn indicators, a chrome-plated steel—formerly plastic—chain guard and, perhaps the most distinctive touch, black chrome on the exhaust pipes, mirrors and passenger grabrails. Also, the aluminum supports for mufflers and footrests received Swiss-cheesing for a high-tech appearance.

Nearly everything about this machine suggests that Honda designers fine-tuned, by vernier engineering, all the details. The suspension and seat have been firmed, not hardened; the seating is, by virtue of the bars' usable range of adjustments, successful; the power, though aggressive, doesn't come in a wild deluge. The bike feels relaxed and balanced, akin to machinery that has been gently aged.

That's an important point. The 1100 stands at the end of several years' development in the 750/900/1100 series. Honda pursued development rather than cutting it off in the second stage of the series, content to stretch new sheet metal over old bones. It seems likely to us, at least, that the thoughtfully developed 1100F might be a more complete piece than a totally new design—say, a VF1100E-type bike—would be in its first year. Development counts; the CB1100F is 1983's best proof of that.

Source Cycle 1983.