-Honda Nighthawk S

-Suzuki GS750

-Yamaha XJ900 Seca

-Kawasaki GPz1000

Four Forgotten Fours

In the process of wrapping up 2025, the ethical thing to do here is admit that I’ve lost the handle on motorcycle sales and values. It’s all over the place – from $60.000 Bavarian land missiles (both old and new) to barely aged Guzzi California’s dropping to three-fifty (what a deal!!) the market’s drunken variance has this old journo stumbling. To those actively buying for profit or fun it’s good info, but the interesting thing to me is how this feast or famine motomarket further exposes those moto-gems previously obscured behind motorcycling’s most popular collectibles. Here’s my personal perspective; back when I was buying a lot of music, my favorites from the album were never the hits played on the radio, and that same exact thing holds true for bikes. More digital and less paper the mainstream press continues to provide most of the information gathered by the world’s riders, and what it deemed worthy is historically praised, covered and recovered until everyone agrees. Mostly. As it often happens the rest slide off into irrelevance (my editorial neighborhood) and its been both fun and rewarding to discover the incredible machines cloaked there. There are certainly other candidates and not all of them are fours, yet these forgotten flyers either played a role in keeping the brand relevant, or a foundation for greatness. Per editorial values, each of these screamers will happily work on modern roads.                      

Honda CB700 Nighthawk S – 1984

Over 750cc tariffs designed to equal things out for US-based Harley Davidson helped create Honda’s Nighthawk S, with 750cc variants sold elsewhere. Having some real life experience, I’d purchased Honda’s 1100cc super sport a year prior, and remember admiring the Nighthawk S (especially stunning in red/white/blue livery) on the showrooms then. To this day the Nighthawk S remains one of company’s most complete packages – borrowing some of the 1100F’s Bol d’Or lines while mixing in conveniences like its standard rise handlebar and shaft drive.      

(In red: made available to Japan, Australia and many Euro markets, Honda’s slightly more CBX 750F put nearly 11-HP more to the ground than the Nighthawk S. Other differences include chain drive, 16/18″ (f&r) Comstar wheels and twin headlamps. It’s actually a bit quicker than the 750 Interceptor. Borrowing heavily from that same sports V45, some Nighthawk S features include adjustable suspensions, hydraulic valves and a fuel gauge. Tidy!)     

Strikingly similar in styling to previous DOHC fours, the Nighthawk’s sixteen-valve multi was a complete new design. Some research shows the engine tuned in both 550 and 650cc editions, with the sports Nighthawk S boosted with more aggressive cam timing and a less restrictive exhaust. Measuring 696cc to just slide under tariff limits, the air-cooled inline is mounted both lower and farther forward in the frame, the latter helped by a ‘short-sump’ crankcase that used an oil-cooler cleverly plumbed into the frame’s forward downtubes to increase oil capacity. Low maintenance was a big sales feature, touting both the shaft final drive and fuss free hydraulic lifters to maintain proper lash. Low, thanks to its twin 16″ Interceptor-style cast wheels and narrow by stashing the alternator behind the cylinders (thanks Yamaha) it bested the competing 650 Seca with a rugged a spur primary gear, a bigger clutch and a six-speed gearbox with overdrive. Plenty quick, period testers loved the ‘Hawk’s twelve-flat quarters and stability. Nicely appointed with its quality 39mm Kayaba fork, matching twinshocks and hearty 276mm front rotors, the Nighthawk S is five-hundred pounds gassed and 125-mph fast, redline in fifth. No doubt many were trashed or cut up by modifiers, Honda’s US-only 700cc Nighthawk S has for decades been praised for its durability, function and application. Could this be the next sleeper collectable?     

Suzuki GS750 – 1976

Moving away from its two-stroke roots and wrapping up ambitious projects like the Wankel-powered RE5 tourer, Suzuki’s GS750 of 1976 was the company’s most important effort to date. Bottom line? Suzuki was getting press building avant garde two-stroke 750’s and rotary roadsters, but they weren’t selling enough of them to justify the investment. Giving Suzuki credit for being transparent in its self-published history, the strong points of Kawasaki and Honda-designed four stroke engines were used as engineering inspiration and direction; the GS750 copying the Z1’s bore centers and valve sizes down to the millimeter…with a few small, critically important details unique to it alone. Simply great best describes Suzuki’s new money-maker for 1976, which grew better and faster with every passing revision.                  

(Probably the biggest complaint directed at the GS750 was its ‘ordinary’ styling, and I don’t get it. First editions were painted either in solid blue or red, with satin black side covers and a plated front fender. Black was very popular in 1978, eventually adding a second front disc and cast wheels on the GS750E model. A brilliant classic, the GS1000 ‘Skunk’ directly descends from the 750. In 16v, 1100 form, the Suzuki remained dominate until 1984) 

It’s worth noting the excellent series of GS750 road tests conducted by members of the US press, who very skillfully detailed the efforts of Sadao Shirasagi as Suzuki’s engine design manager. We find out later that Suzuki in Japan approached Daytona winner/editor Cook Neilson and the staff at Cycle to evaluate prototypes, resulting in important adjustments to production machines. Back home and very much needing to get the firm’s first big-bore four-stroke right, Shirasagi’s application based the unit on a burly, full-circle roller bearing crank and Kawasaki-style gear-drive primary. Playing it safe, the two-cam, two-valve (35.5mm inlet, 30mm exhaust) is tuned conservatively with 8.7 compression pistons, but the over-square four spools quickly. Four 26mm Mikuni tuck into a factory airbox, and the GS 750 is old enough to still fit points ignition. With a factory rating of 68-HP Suzuki’s five-speed 750 was nearly Z1 quick, but good as it was, it wasn’t the engine that made it a sales success. Solidly strong and true, it was engineer Hisashi Morikawa’s frame that transformed the ordinary GS750 into extraordinary; especially considering its standard 35mm fork (27-degrees rake) and twinshocks appear as regular market fare…right down the Suzuki’s el-cheapo plated spokes. As so many discovered, looks can be deceiving and the balance achieved came from proven fundamentals perfected by English and European makers. There is more -way more- to this amazing story, but the conclusion is 1976’s Suzuki GS750 was the finest big bike from the Japanese yet.          

Yamaha XJ900RK Seca – 1983

There’s many reasons Yamaha’s biggest Seca didn’t sell when Yamaha released it, and even more reasons why it should have. Specific instances working against 1983’s stunning 900 Seca include an inability to run with open classers like the GPz1100 Uni Trak, GSX1100 or Honda’s 1100F – the machine it most resembles. At least on the surface, and there’s a point to make. As told to me in the mid-2000’s by a long time Yamaha employee, during the firm’s foray into the four-stroke waters Yamaha seemed determined to beat Honda at their own game…but couldn’t.              

(Sold in other markets as the XJ900 and painted differently, this black w/red and gray graphics is a 1983 Euro import. Slick and efficient, Yamaha’s patented three-clock dash is offset by adjustable bars and a gauge for the 5.8 gallon fuel tank. Shaft drive put the Seca 900 into the sports-tour realm, but period testers praised the 900 for its sporting prowess, due in large part to the bike’s adjustable suspensions which helped limit pinion climb. After 1984, Yamaha continued development, bumping displacement to 891cc and adding a frame mount fairing. In white and blue, this XJ900 is from 1989)    

So while all this might seem negative, history shows the XJ900 outliving its 1983 competitors by decades, serving faithfully for many thousands of British and European riders. Some quick background looks back at Yamaha’s first four-stroke open-classer; 1978’s shaft drive XS-Eleven four, but that quickly leads to the company flexing its engineering muscle with twos, threes and pure-sports singles. Back to the new designs, in 1981 the shaft drive Maxim 650 four was introduced, it’s cruiser motif illustrating what was selling then. Narrow with its alternator located behind the cylinders, 650 and 750cc variants of the sports Seca grew from the Maxim blueprint, leading into what should have been a memorable release. Rolling on a beautiful pair of 18″ cast wheels, the 2v, 853cc inline used 9.2 compression pistons, 35mm Mikuni CV carbs and CDI ignition. Inside, a very Honda-ish HiVo primary drives the transmission, but the editors as Cycle heaped praise; calling Yamaha’s new XJ900 “Motorcycling’s best handling shaftie.” Slick, very well finished and 130-mph fast, some reports say President Reagan’s 45% (Harley) tariff in April of ’83 the main reason so few XJ900 Secas came here – perhaps only 1000 total. Allowed the American dream for only one year, in 1984 the XJ900 was opened to 981cc, new 36mm carbs and redone with a frame mount fairing to address stability complaints. Various S and GT editions emerged and the line continued until the 1994-2004 900 Diversion. Another quality build, the Diversion featured a new chassis and a downdraft-type cylinder head.    

Kawasaki Ninja 1000R – GPZ 1000RX – 1985

It would be all too easy to wax on about this motorcycle, how I discovered it and why I believe its place among motorcycling’s most forgotten is particularly egregious. An all new design for 1985, the Ninja 1000R (GPZ 1000RX elsewhere) went public just as momentum for 1984’s GPz900R was growing, but production continued for three years until replacing the battle cruiser’s steel frame with an updated unit in aluminum, and calling it the ZX10/Tomcat. Sandwiched between two legends, the mighty Zed 1000 sold in respectable-to-impressive numbers, given the interaction I’ve enjoyed from riders all over. “It’s an impressive old rocket,” wrote one New Zealander; “Crap brakes and it’s pig heavy…but still going strong.”           

(Full frontal action compares the 1000R to the ‘Top Gun’ favorite. Vastly different streamlining is applied to the 1000, more radius and down-force technology. Dash includes fuel and coolant gauges, with a neat tacho/voltmeter feature. Clip-ons are top mounted for all-day ergos, yet the big Zed maintains a sports profile. Starter/clutch replacement is the enemy, but the overall finish was Kawasaki’s best to date. (Images: Young Machine/WMM)      

Described as a heavyweight puncher with more power than agility, the GPz demands respect for its size and thrust. Ironically, it is those very attributes that define the bike’s character, and even its eventual role. For 1987, Kawasaki mated a modified GPz 900R frame with a re-tuned 1000RX engine to make the ZG1000 Concours, which carried on for another twenty years. Displaying why Kawasaki as a company is among motorcycling’s greatest, the investments made to introduce a new Zed (replacing the radically popular old one) paid dividends beyond their wildest dreams. In this case, that path to excellence resembled the 1000RX’s ability to punch through air; and under that ABS is a massive, battleship-grade steel perimeter that both wraps around the liquid-cooled inline and ties it up with a bolt-on cradle. More sturdy everywhere but retaining its distinctive left-side cam drive, increasing bore and stroke took displacement from 906 to 997cc. Tuning details include light 10.2 comp pistons, four 36mm Keihin carbs and transistor ignition. Back inside, larger valves (38.5/32mm intake/exhaust) worked with hand polished intake ports to produce an under-stressed 125-hp. Through a close-ratio six-cog box and geared for Autobahn superiority, the 10000RX poured on speed like no Kawasaki before it, and while the bike’s heavy steel frame, burly suspensions and glossy cycle parts increase stability and comfort, it all adds up. Long, low and with an engine that signals the happiest part of my brain, this is a motorcycle aimed at a specific kind of rider. Not all Ninja’s are created equal, and the sum of the 1000RX makes it more effective as an open highway blaster then a canyon carver.

Resale not withstanding, each of these forgotten four share a great deal of historical value. Like anything, some will be better than others – one example being English and Euro riders not having to worry about XJ900 parts like US owners would. When reaching back for 70-90’s machines, available spares and wear items (like tires, chains and brake pads) should be a strong consideration when picking a favorite. Known for its rapid technology and oft-changed models, some Japanese models can prove to be more of a challenge. However, in researching these four standouts various forums and owner’s groups were discovered, each ready to welcome in those new to the breed. Rad rides and like-minded camaraderie have long been the bedrock of motorcycle enthusiasm. May that always be. Nolan Woodbury                   

Kawasaki GPZ 1000RX

Engine: 997cc DOHC 4v liquid-cooled transverse four
Pistons: 10.2
Intake: 4 x Keihin CV36
Ignition: TCI/transistor
Transmission: 6-speed
Primary/final: Gear primary, chain
Chassis: Twin spar cradle 
Forks: 40mm KYB anti-dive
Rear: Uni Trak monoshock
Brakes: 2 x 280mm / 1 x 260mm rear (1p)
Wheels/tires: 120/80-16 (f) 150/80 16 (r)
Weight: 580-lb, 158-mph