Years produced: 1977-1978 (1st generation)
Claimed power: 49hp @ 9,000rpm
Top speed: 111mph (period test)
Engine type: 549cc OHC air-cooled inline four
Weight: 431lb (wet)
Price then: $1,745
Price now: $750-$2,000
As the last of Japan’s Big Four to introduce 4-stroke engine technology to its lineup, Suzuki clearly appreciated that when it finally went up to bat against the other 4-strokes with the Suzuki GS550, it needed a home run.
There was no question that Suzuki would have to enter the game. While 2-stroke engines had served Suzuki well in a host of road bikes, including the classic 500cc Suzuki Titan twin and the Suzuki GT750 and 550 triples, the buying public was increasingly shunning smoky and often peaky 2-strokes for cleaner-burning, quieter 4-strokes. By 1976, every one of the Big Four except Suzuki was producing a range of 4-stroke fours. Enter the new GS line for 1977.
All new machines with all new drivetrains, the Suzuki GS550 and its big brother, the Suzuki GS750, were Suzuki’s answer to the 4-cylinder, 4-stroke equation that was defining the middleweight and heavyweight classes. Covering its bases, Suzuki also introduced a small-bore, 398cc 4-stroke twin, the Suzuki GS400.
The bigger 750 was an instant hit with buyers and was Cycle World’s pick for its annual Best of Breed in the 750cc class. Reviewers and riders alike raved about the new 750, yet while the smaller Suzuki GS550 was essentially a scaled down 750, it failed to capture the same level of attention, at least from the motoring press.
A better middleweight
It could be that the Suzuki GS550 simply didn’t have enough flash. True, its styling might have been somewhat subdued, but at a claimed 49hp it was no slouch, with quarter-mile times in the sub-14 second range. That put it ahead of Honda’s go-fast looking Honda CB550F Super Sport and ahead of Suzuki’s own GT550 2-stroke, which would be on showroom floors for one more year while Suzuki’s new middleweight 4-stroker established itself. All in all, the new Suzuki GS550 mill was a smooth performer, save for a pronounced buzz at engine speeds above 5,000rpm, unfortunately exactly where it produced the best power.
A single-disc front brake and drum rear were hardly exciting but were well paired and more than adequate to haul the 431- pound machine down to a stop in less than 125 feet, excellent performance for the day and still good today. The bike’s 6-speed gearbox, essentially a GS400 twin transmission and not a scaled-down GS750 box, as might be expected, was more than up to the task of transferring the 550’s power to the rear wheel, although some tAesters faulted its shifting quality, finding it notchy and with a pronounced false neutral between fifth and sixth gears.
Suspension was standard fare, with telescopic forks up front and traditional pre-load adjustable shocks at rear, calibrated to deliver a firm ride without the wallowing experienced on other middleweights, which tended to have somewhat softly-sprung suspensions. Cycle called it “an excellent mountain road darter.”
And it was comfortable, too, with a flat, broad seat allowing the rider to place his bum where he wanted it, while giving comfortable two-up riding. Following a pattern laid down by Suzuki’s 2-stroke triples, the Suzuki GS550 was endowed with the riding attributes Suzuki’s customer had come to expect, namely, long range comfort.
It was, in fact, a great all-arounder, yet the motoring press didn’t know what to make of it. Cycle World called it understated, almost bland, “a machine with any number of solid virtues, but they’re subtle virtues, the kind that take some familiarity to appreciate.”
But the motoring press notwithstanding, the little GS performed its mission well, delivering a solid home run. The first year model was a complete sellout for Suzuki, which, intelligently enough, offered the bike essentially unchanged for 1979, along with an extension of the theme in the guise of the GS550E. With alloy wheels, a rear disc brake and a stepped seat, the 550E offered the visual punch apparently lacking in the standard.
The standard GS550B (as it was internally designated) bowed out in 1979, replaced by the E and the new GS550L, whose raised bars, steeply stepped seat, bobbed pipes and revised steering geometry reflected the latest trends in cruiser styling.
Although not exactly plentiful, good 550s aren’t too hard to find, either. Engines hold up well, although most bikes lost their original exhaust systems years ago and have been replaced with aftermarket 4-into-1 units — fine assuming attention has been paid to the inlet side of the equation. Good looking, solidly built and reliable as a stone, Suzuki’s GS550 is a solid performer that still makes a great road bike today.
Middleweight rivals to the Suzuki GS550
1977 Honda CB550F Super Sport
- 50hp, 102mph
- Single disc front, drum rear
- 423lb (dry)
Launched in 1975 and based on Honda’s original half-liter CB500, the Honda CB550F Super Sport was Honda’s attempt to inject a little pizzazz into its middleweight offering. Visually, the biggest thing separating a CB550F from a standard CB550K is its graceful 4-into-1 exhaust, which somehow manages to look a little ungainly compared to the similarly-styled system on the diminutive but lovely CB400F.
And while the swoopy exhaust and Super Sport designation could lead a prospective buyer into thinking this is a machine made to perform, the truth is it’s not. That doesn’t mean a Honda CB550F isn’t a pleasant-riding mount, it’s just that the performance doesn’t quite match the hype.
Zeroing in on the F’s performance, period testers found the CB’s brakes good but faulted its handling at the edge thanks to limited suspension travel, and some complained of vague shifting with the 5-speed box. Niggling complaints, really, and thanks to typical Honda reliability, CB550s of any stripe are nigh on indestructible. Sure, the cam chain guides can wear, making the engine sound like it’s in its death throes, and the chrome has a bad habit of flaking off, but when it comes to early multis, you’d be hard-pressed to find a simpler, more reliable four than this. Parts are plentiful, and for now at least, the bikes are cheap.
1977 Kawasaki KZ650
- 64hp, 120mph
- Single disc front, drum rear
- 472lb (dry)
Introduced in 1976, the Kawasaki KZ650 was Kawasaki’s entry into the budding 4-stroke middleweight category, except Kawi decided to give the category a little bump by one-upping the competition and making its middleweight four a 650.
That 100cc advantage shows up on the spec sheet, with the Kawi producing a claimed 15 horses more than the Suzuki and 14 more than the Honda. It shows up on the road, as well, with the Kawi topping out almost 10mph faster than the Suzuki GS550.
Not surprisingly, it’s also the heaviest of the trio, coming in almost 50 pounds over its rivals, so it needs that extra oomph to put itself to good effect. And that it does, with quarter-mile times in the mid-13s and a top speed of 120mph.
Period testers considered the 650 a downsized 750 rather than an upsized 550 middleweight, heaping praise on its powerful engine and generally good handling. A short wheelbase makes it twitchier than its bigger brothers, the KZ750 and KZ1000, but that also means it handles well in the twisties. The biggest complaint from most quarters centered on the engine’s pronounced buzz above 5,000rpm, rendering the rear-view mirrors useless.
Shim-under-bucket valve adjustment complicates maintenance, but they’re otherwise solid, reliable machines built for the long haul. Fast, fun and still cheap. MC