Cycle News - Archive Issues - 1980's

I",p-ression: J. 984 Honda CB700SC Nighthawk S Tariffcheating world beater By Dale Brown Last year's Honda Nighthawk broke new ground, combining sport and custom styling elements in a performance-oriented package. This year's Nighthawk S -breaks even more new ground. Gone are any remnants of custom styling, but the machine still retains strictly American char- 24 acteristics. Thanks to a decision made by the Imernational Trade Commission and supponed by the Reagan administration, most imported motorcycles over 700cc are subject to additionaltariHs over the next four years. As a result, many Japanese motorcycles that were marketed previously in the 750cc class, now displace no more than 699cc. In the case ofthe Nighthawk S,the machine began life on the drawing boards as a "California hot rod" transverse air-cooled four-cylinder 750cc spons machine, a hot Camaro to the Corvette role of the 750 Interceptor. Then the ITC handed down its decision. In the wake of the announcement, Honda reduced the stroke of the ighthawk lO bring it down under the 700cc tariff minimum, winding up with a very oversquare motor. Even though there are only 50cc displacement difference between the Nighthawk and the ighthawk S, theS hasa 7.lmm bigger bore. Honda did go ahead with the 750 model for other countries, designating it the CBX750 and equipping it with chain drive. This tariH-skirting process didn't deprive the American public of a fast, fun, shaft-driven high-performance motorcycle. The motor is a third generation version of Honda's 45cubic-inch transverse four-cylinders. Although it looks like last year's 650, much has been changed. The S retains the four valves per cylinder and the hydraulic valve adjusters of the '83 model, but the S runs cams with greater lift. In the lower half of the motor, power is still transmitted by a gear off the crankshaft between the third and fourth cylinders. When the designers went to a l6-inch front wheel up front, it allowed them to lower the engine and move it further forward in the frame. As a result, Honda was able to redesign the six-speed transmission and put all the shafts on the same centerline, rather than the stag.gered 650 version. With the engine moved down and forward, keeping the engine compact was still a goal. Honda managed to reduce sump size by running oil to the cooler via the frame downtubes. Honda's advertising claims 80 horsepower for the molOr. We didn't have a chance to dyno the bike, but all the parts of our bodies involved in holding on to the motorcycle under hard acceleration will gladly testify that the Honda is fast. Very fast. Starting the 698cc powerplant involves a fair amount of choke, especially in southern California wimer weather; mild as that may be. We found that we needed to keep the choke at least partially on through the first few miles of riding. Once warm, the hilth-revving en- gine (10,500 rpm redline) produces its own sweet sounds. Off idle, you get chamber music. At 4000 on the tachometer, it's jazz. At 6000, rock. When you getlO 8000. you're talking heavy metal output. As strong as the Nighthawk S is, it's still a very tractable motorcycle and very easy to ride around lOwn. The machine will pull from under 2000 without any significant coughing or other protest. We found that for most riding around lOwn, it was best juSt to leave the bike in third gear and take advantage of the wide power band. While the Nighthawk was perfectly comfortable in a commuter role, it certainly doesn't sound like a commuter machine. It sounds, well, authoritive, with a distincl snarl in the exhaust nOle. Emhusiasts will love it, bUI Granny will certainly notice the sound if you lake her for a ride on the back. Last year's Nighthawk was also fast from stoplight to stoplight, but couldn't holda candle to ils Interceptor cousin for handling. This year's effort has certainly improved. The biggest change is the adoption of 16-inch wheels, wide rims and matching rubber. We continued to speak in unabashed favor of l6--inch fronl wheels because of the wonderfully responsive steering that has accompanied them on bikes we've tested. This change, along with the resultam chance lo lower the engine mass, accoums for the greatest improvemem over the 1983 Nighthawk. Our test bike proved to be great fun in the twisty stuff. Effort required 10 getlhe bike going in either direction was minimal, and the results maximal. Just give the bike a liltle nudge in the direction it should go and it goes. Even the resident GPz afficianado was begging for the Honda on weekends. When we picked up the 'Hawk from Honda, their technical reps said thaI we probably would not notice that il was shaft-driven. Well, we did, but torque reaction as result of chopping the throttle in the middle of a corner was minimal, and after awhile we simply adjusted and forgot about the shaft. A beefy telescopic fork 'assembly with 39mm tubes connects the from wheel wilh the steering head. The springs and oil in the fork are aided by air pressure. As delivered from Honda, the from suspension proved to be perfectly satisfaclOry for riders in the light and medium weight categories, while those heavies in the crowd felt they were getting a little 100 much feedback on road conditions through the handlebars. Never was the damping or rebounding action harsh or unpredictable, so the whole crew gave the suspension good grades. Rear suspension duties are taken care of by a pair of oil-damped shocks, this year from. Kayaba instead of Showa units previously utilized. They worked well enough so that nobody complained, but the plush ride we've encoumered with some of the risingrate single shock systems was lacking. The tubeless Bridgestone tires that come stock on the Nighthawk proved to be more than adequate during our test, but with the Nighthawk's capabilities, we'd bel that a lot of good and sticky aftermarket rubber will be finding its way on lo the cast aluminum rims. With the alternator remaining behind the cylinders, the engine is quite narrow and the ground clearance more than adequate. Honda continues to put "feelers" on the footpegs; ours remained virgin. The 700 also retains Honda's "fivespeed plus overdrive" transmission. The gear ratios are well-spaced, but shifting was a bit clunky. especially

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