CB 750SC Nighthawk
Honda CB 750SC Nighthawk
Air cooled, four stroke, transverse four
cylinder, DOHC, 4 valves per cylinder.
Bore x Stroke
67 x 53 mm
4x 34mm Keihin
CDI / electric
75 hp 54.7 kW @ 8500 rpm
64 Nm @ 7500 rpm
5 Speed / chain
41mm Air assisted forks,
139mm wheel travel.
Dual shocks, 5-way spring
preload, 107mm wheel travel.
Single 296mm disc 2 piston caliper
31.2 in. / 792mm
12.7 sec / 103 mp/h
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
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
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