Honda CB 750 Nighthawk

1991 Review

Once upon a time all street bikes fit into one standard type, created for a wide variety of tasks. They weren't cruisers or touring bikes or sport bikes, but they could be all those things. If you wanted a tourer, you added a fairing and luggage. If you wanted a styling statement for cruising, you changed the tank, seat and bars and added chrome to suit. If you wanted a sport bike, low bars, aftermarket shocks and a fairing were the essential additions. Most riders left their bikes basically stock, though, since they worked well for a wide variety of tasks. By the mid-70's, street bikes, especially those from the Japanese makers, began to look very much alike, with similar styling and the ubiquitous air-cooled, in-line, four-cylinder engine. The name that stuck was "universal Japanese motorcycle," or just UJM.

When the time came to break that mold, the Japanese manufacturers responded with market segmentation. First there were hot-selling cruisers, which were fun on Saturday night but not comfortable enough for extended rides nor as adept as regular bikes at negotiating twisty roads. Next full-dress tourers appeared, great on the expressway but awkWard in tighter roads or traffic. Then sport bikes became a hit, which was fine if you wanted to charge corners but less exciting if your plans included traveling or you had a bad back. New engine configurations came along too. Each new trend not only carved off a piece of the market, it gradually eclipsed the old do-it-all school. Eventually, motorcyclists looked around and noticed the UJMs were gone. Almost any new motorcycle you bought forced you to focus on a certain type of riding and to exclude other types to some extent.

Problem was a lot of riders liked those UJMs. The do-it-all character suited their riding plans perfectly, and the in-line four looked, worked and sounded the way they wanted an engine to. When the Japanese motorcycle makers realized they were deserting their roots, the pendulum began to swing back. In recent years we have seen more and more standard-style motorcycles: Honda had the Hawk and CB-1. Kawasaki re-created its UJM for the '90s with the 550 Zephyr and soon the 750 Zephyr. Suzuki launched the GS500 and VX800 and this year will add a wide-focus 1100 four to its line. Yamaha hung on to the 600 Radian through 1990, for many years the only UJM around.

Now we have come full circle. Honda has created a modern version of the original UJM with the 750 Nighthawk. It wasn't just another model for Honda. Lots of research and development went into discovering and perfecting what this reborn UJM would be. From all the prerelease hoopla and sneak previews, Honda also made it clear that it believed the new CB750 to be an exceptionally important model. Best of all, by combining existing technology with some new pieces Honda kept the price to an almost unbelievable $3998. That is hundreds less than comparable twins and even $300 below what the 400cc CB-1 sold for last year.

How did Honda make the 750 Nighthawk so affordable? Well, to start with, it is air-cooled, which avoids the expense of a liquid-cooling system. There is just a single disc brake up front, and the rear is a drum. The suspension has few adjustments, just stepped preload collars on the twin rear shocks. The transmission has five speeds, not six. Unlike the 700 Nighthawk S of years past, there is 0-ring-chain drive, not shaft. And these two Nighthawks share more than the name. The new Nighthawk uses some of the same engine components from the 700 Nighthawk's era, although not exactly from the 700. It is based on the CBX750, a member of the same engine family as the 700. The CBX750 was sold in other markets when the 700 was sold here and has served as the basis for police bikes in Japan since then. The 750 Nighthawk engine is not lifted verbatim from that bike, but the CBX750 is the source of many of the CB750 Nighthawk's components and the engine is essentially the same. To keep the CB750's cost down, the bells and whistles-like a self-canceling feature for the turn signals-have been thinned out. Even the centerstand is an option (one that we recommend).

Since the under-$4000 price point was a design requirement from the beginning, it is somewhat surprising to consider what the Nighthawk has: an aluminum oil cooler, 16 self-adjusting valves, automatic cam-chain adjuster, beefy 41mm fork tubes, running lights in the front turn signals, dual-bulb taillight and all the other amenities you'd expect-passenger accommodations and tach are standard. Best of all, it works well and is fun to ride.

Honda aimed for a broad spread of power rather than explosive top-end. Cam timing is conservative, with zerodegree overlap, significantly less than the 700 Nighthawk. The valves are also slightly smaller than the 700's, as are the exhaust pipes' inner diameter. These changes were made to give the CB750 more low-rpm power and response than the Nighthawk S or the CBX750 and to improve fuel mileage.

We can get the negative remarks out of the way immediately: the engine is cold-blooded, requiring longer than average warm-up to be fully ready to respond without choke. However, even on a cold morning, putting on your helmet allows enough time to warm it sufficiently to pull away smoothly with the handlebar-mounted choke lever partially engaged. Even when warm, there is about half a beat of hesitation when you open the throttle from idle. (We rode three different machines at Honda's introduction, and each was a little different in this regard; our test bike was the worst.)

Once off idle, the Nighthawk eases up to about 3000 rpm, making more power than the 700 or the CBX750 (tested August '84) but still not fully alive, then comes into its own. Power builds steadily all the way to redline at 8500 rpm. At an indicated 60 mph in top gear, it's showing about 4000 rpm, pleasantly into the powerband but well below the range of slight buzziness around 6000 rpm. You shouldn't expect RC30-beating acceleration from the CB750, but it's no stone either. Our sample laid down a 12.28-second run in the quarter-mile at 108.4 mph. That's stronger than the comparable V-twins but not as fast as the 600 sporterswhich fetch about a grand more at the cash register than the Nighthawk.

The 34mm Keihin constant-velocity carbs offer positive, linear response with none of the abruptness of some of their brethren. With help from the more tractable engine, they can deliver lots of miles per gallon too. Our best tank, recorded after a few hours of moderate-speed highway use in the rain, came up 59 miles per gallon, but our average was 44.8 miles per gallon. That will get you about 175 miles before you have to switch to the .8-gallon reserve-if you spent the time to squeeze in the last .4 gallon of fuel when you topped off.

The exhaust system is a four-into two design with a balance tube connecting the two sides just ahead of the mufflers. The resultant exhaust note is quite pleasing to the ear and is subdued so as never to attract undue attention. Honda used some new internal designs to create a pleasing cadence and filter out the objectionable frequencies but maintain the deep tones. It seems to work; the editor complained that his dogs didn't come out to greet him when he rode the 750 Nighthawk home.

The excellent shifting and smooth, light clutch of the old Nighthawk are preserved in this machine. It shifted quietly and easily with negligible clutchlever effort though the shift lever failed to index if the shift was hurried. Finding neutral was easy; we had to learn to be aggressive when shifting through neutral, in fact. The driveline is smooth, quiet and lash-free.

The rectangular-section swingarm was lifted from the Japanese-market CBX750, but Honda create a new double-cradle mild-steel frame for the CB750 with new dimensions. The wheelbase stretches 59.1 inches, and rake and front wheel trail are 29 degrees and 4.25 inches, respectively. That wheelbase is long enough to make it stable and roomy without ponderous steering. There is enough lock to permit the Nighthawk to turn in a surprisingly tight circle, and steering is light and stable at those low speeds. You have excellent control when splitting traffic or crawling along through a tight spot.

The 41mm fork's innards are similar to the fluted pieces created for the CBR600, which offer excellent centering and therefore more precise metering and more consistent damping. The dual rear shocks use a new Showa valve system aimed at producing similar results there. While the bike's bargain price would seem to rule out topshelf suspension, these pieces work surprisingly well. The spring and damping rates give a comfortable ride on bumpy roads and provide excellent tracking through rough corners. Heavier riders found it slightly soft during aggressive riding in smooth corners, and lighter riders rated it just a bit taut in the bumps. In other words, Honda hit the middle ground quite well. The suspension works better in sporting situations than a few sport-bike pieces and yet provides more comfort than many bikes with less aggressive missions.

The light, predictable steering continues when the speed increases and you start leaning deeper into corners. Though the rear end can be persuaded to wallow a little bit if you bobble in a fast corner, it damps itself out quickly and that reassuring stability never disappears. Though the cast wheels won't accommodate the ultrawide radial rubber that graces sport bikes these days, the footprint provided by the stock Dunlops is big and solid enough to let you confidently use all of the substantial cornering clearance. During extended hard cornering, the tires heated up and got a bit greasy, but anyone who plans on doing a lot of that can fit stickier tires.

Though the brakes are not exceptionally strong by Supersport standards, they are plenty strong enough for the job at hand and provide excellent control. The drum rear brake allows excellent modulation in a panic stop, and the front brake, which uses a large ST1100 rotor, will lock up the tire if called upon to do so. With the well controlled suspension, the bike can make short, well-controlled panic stops with little practice.

Many riders will be attracted to the 750 Nighthawk for its ergonomics, and if it fits you as well as it does most of us, you'll be very comfortable indeed. Honda wanted a no-kinks riding position, and even our 6-foot-4 road test editor was pleased with the space he had. His only complaint, and it wasn't a big one, was that the forward portion of the fuel tank, which widens quickly to the front, splayed his knees, which ended up farther forward than other riders'. Like other riders, he was extremely appreciative of the roomy, flat, dual-density saddle, which Honda developed through extensive U.S. testing. Though not as good as the very best saddles of the UJM era, the Nighthawk seat provides more comfort and flexibility than any comparable saddle available today. Honda could have provided deeper foam but probably would have begun to lose too many short-legged buyers. We'd love to see Hondaline add a wider, deeper (but just as flat) saddle to its list of options.

The 29-inch-wide handlebar has a modest rise (about 4 inches from the cla@p), which pleased every tester through an extensive variety of situations. It's wide enough for control but not so wide as to be clumsy in tight spots. It is high enough for comfort at low speeds but not high enough to make you pull yourself forward at rapid highway speeds. And of course, if you don't like it, you can easily swap it for any of the hundreds of bends available from the aftermarket. This is a good, old-fashioned design, no castings or special mounts. The footpegs are in a conventional spot, neither sporting rearsets nor forward mounted highway-peg style. They too garnered praise for their comfort and roominess from everyone who rode the Nighthawk. There is also plenty of room for a passenger, though if we owned the CB750 the grab strap running across the forward portion of the passenger's section of the saddle would come off the minute we got the bike home.

Though there aren't a lot of extra widgets and add-ons to hook buyers, the details are very well executed. The deeply chromed mirrors are oriented horizontally to provide a wide view of traffic behind you. The headlight gives exceptional illumination and has a plastic lens to keep stones from cracking it. The controls all fit and work smoothly. There are push-to-cancel turn signals, and a fork lock is integrated into the ignition. The traditional dual instruments reside in nicely chromed cases and are well lit (though if we owned the CB750, we would smoke the high-beam warning bulb to make it a bit less glaring at night) and easy to read. The horn is the usual hopeless bleater. Two grab rails incorporate bungee hooks. Lifting the 494-pound (tank full) machine onto the optional centerstand is easy. The engine isn't as heavily polished in some places as it might have been in days past, but the only place where the finish looks a bit rough is at the two-into-one welds of the exhaust system. The new Nighthawk should require substantially less maintenance than comparable machines. You won't have to adjust valves, cam chain or ignition timing, and other routine services are quite simple, thanks to the exceptionally easy access. You can get to the tool kit two helmet holders and a tail-section storage compartment by unlocking the seat lock located just under the tail.

The battery and fuse box are accessible just by popping off the right side panel. Remove the left side panel and four screws to reach the paper airfilter element. The oil filter is a screw on type located at the front of the engine; you'll need to wear gloves and long sleeves to unscrew it if the header pipes are hot. Checking the oil requires unscrewing the dipstick; Honda deliberately left out a convenient oil-level sight glass, feeling it was inappropriate for the bike's character.

The character imbued by the styling is a mixture of traditional and fresh. The overall lines and single candy-red color are UJM traditional, but the flowthrough bodywork, five-spoke cast wheels and hefty fork tell you this is not a decade-old bike. You discover that too by riding it. The decade of development shows itself in this reborn UJM, but the pleasures of the genre haven't been left out either.

If you feel that motorcycling fashion and prices have disappeared in directions where you have no interest in following, take another look. And welcome back. The good old days have returned, better than ever.