SUZUKI GS1000S
Potent engine, sweet handling and AMA Superbike style... Suzuki’s GS1000S has it all
We take a ride on Suzuki’s musclebike with race styling
How come Suzuki’s GS1000S is such a great bike? When the company’s first four-cylinder four-stroke, the GS750, debuted in 1976, its engine architecture was remarkably similar to that of the all-conquering Z1. Suzuki’s masterstroke, though, was in the rolling chassis. The GS750 is still widely credited with being the first Japanese ‘superbike’ to have handling equal to its engine performance.
The GS750 was as quick (or quicker) than any other contemporary 750 – but handled a whole lot better. Sales were as brisk as the acceleration and Suzuki had a winner on their hands. How could they make such a good thing better? By going large with the GS1000, that’s how. But it was more than just a bored-out 750. Learning from their experience with the GS750, the new model featured an engine that was both bored and stroked to give 997cc. What’s more, the 90bhp mill was an astonishing 10lb (4.5kg) lighter than the 750. Suzuki’s design engineers had enough confidence in the GS1000’S electrical components to dispense with a kickstarter, which accounted for some of that weight.
They also calculated that they could go with smaller big-end bearings, a lighter crank and lighter crankcase too – all without sacrificing any of the GS750’S impressive reliability. They were right, too. The GS1000 engine is certainly one of the most reliable and durable engines of the air-cooled, twinshock, musclebike era, with road and drag racers pushing the original dohc unit to astonishing levels of performance. For road riders, that translated into class-leading speed with sweet road manners. It was a winning combination.
The GS range was proving a winner on race tracks, too. In 1976, across the pond in the USA, a young rider named Wester Steven Cooley was making a name for himself in the new AMA Superbike class aboard a fairly ill-handling Kawasaki. After picking up a couple of podiums and his first race win in 1977, he switched to the new Yoshimura Suzuki team for 1978 (see overleaf). After taking a couple more race wins in 1978, Wes Cooley gave Suzuki their
first AMA championship the following year, backing that up with another title in 1979. The GS1000 had arrived. And to cash in on its arrival, why not build a road version of Cooley and Yoshimura’s successful racer? Although Suzuki never explicitly made the connection when marketing the GS1000S when it was launched in 1979, the look of the new model could hardly have been coincidental. The ‘new’ S model was largely a cosmetic makeover – conventional rear shocks (rather than the air-assisted units of the existing EN version of the GS1000) and an 18in rear wheel were the only specification changes – but the stunning red and white paint job and that AMA-style bikini fairing made all the difference.
With that in mind, it seems slightly surprising that the GS1000S only remained in Suzuki’s range for two years – 1979 and 1980. For 1980, slightly longer silencers and a blue and white colour scheme were the only significant revisions – though there were slight variations to the clocks and mirrors for different markets. But the truth is, the early ’80s were a time of rapid development in the bike world. Single-shock rear suspension, four-valve cylinder heads and liquid cooling were just around the corner and the GS1000 represented the last fling of the old order – though it was none the worse for that.
Forty years on, the GS1000S has become the most desirable GS1000 model to own. I can see why – and so can Lancashirebased Martyn Kenyon, who owned one back in the day and is now the very satisfied owner of this launch-year 1979 model. “I bought a red and white one brand new in 1980,” he explains. “My father-in-law George Clarke was the local Suzuki dealer, so I could usually get a bit of a deal. I loved the bike and kept it for about 10 years before trading it in. I went everywhere on it – down to the south of France, all over. I wasn’t really looking for another one, but I was just browsing ebay on holiday last year and spotted this. I showed it to my wife and she said: ‘You ought to get it...’ The next thing I knew, I was on the phone to the seller – Paul Brace (properbikes.co.uk) – asking him all sorts of questions before heading down south to pick it up.”
That was last September, and since then Martyn and mate Steve Slater have spent some quality shed-time recommissioning the bike. Steve’s come round to Martyn’s to see what we’re up to, and the two of them fill me in on what they’ve been doing. “Paul’s a top guy,” Martyn continues. “The bike was exactly as he described it and is in really good, original condition. It’s an Italian import, but came with a dating certificate and all the documentation to register it, so it’s got an age-related UK registration now. And, being over 40 years old, it doesn’t need tax or MOT.”
What Martyn wanted was a bike that he could just get on and ride. So, in deference to the GS’S age, he and Steve drew up a list of jobs to get the bike ready for this summer. Steve takes up the story: “The engine ran quietly, without any smoke or rattles,” he says. “All it really needed was a thorough service. We changed the oil and filter, fitted a new air filter and points, reset the ignition timing and replaced the spark plugs. We also fitted a new fuel tap and pipes, stripped the carbs, got them ultrasonically cleaned and rebuilt them using Keyster overhaul kits. Once back on the bike, we balanced them and that was the extent of the engine work.”
Next, it was the turn of the rolling chassis to come in for a little attention. “The swingarm and rear brake torque arm were a little tatty,” Steve explains. “So we masked off the bearings – the GS1000S has needle-roller swingarm bearings
‘I CAN SEE WHY ITS HANDLING WAS HAILED AS A
SERIOUS STEP FORWARD FOR JAPANESE SUPERBIKES’
as standard – and stripped and painted both of them. Then we repacked the bearings with grease and refitted the swingarm, having had the wheel spindle, nut and washer and the chain adjusters replated while the rear end was stripped.”
Up front, the pair checked the head races for wear before regreasing and adjusting them, and fitted handlebar-mounted mirrors to replace the fairing-mounted originals. “They were pretty useless,” smiles Martyn. “You could just about see your elbows in them, but not much else. We also replaced the screen as the original had crazed a bit, then drained, flushed and refilled the forks with oil and fitted a pair of new tyres. And we stripped and ultrasonically cleaned all three brake calipers, as well as fitting new stainless-steel pistons, fresh seals, new brake hoses and pads before changing the brake fluid and vacuum-bleeding the system.”
The electrical system needed a bit of a refresh too, as Steve explains. “The wiring loom looked in pretty good condition, but we separated every single connector, checked for corrosion and sprayed them all with contact cleaner. While we had the fairing off to sort the screen, we fitted LED bulbs in the instrument cluster and a new headlight (the original dipped the wrong way), plus a new Motobatt battery and a front brake light switch as the existing one only worked intermittently. But it was the indicators that gave us most trouble.
“The left-hand indicators would only work occasionally. Eventually, we traced the problem to the control unit for the self-cancelling function. A new unit would have cost £400, so I had a go at repairing the original. With the cover off the unit, it looked like a bit of moisture had got in. I could see a fair bit of verdigris around the relay for the left indicator circuit. I had to unsolder it from the PCB to get to the contacts to clean them up – but luckily, once it all went back together everything was fine.”
Martyn wanted a bike he could just get on and ride, with only routine servicing to worry about. After a winter in the garage, he thinks he’s just about got that with his GS – and he’s happy to prove it to me. I’m off out onto the moors surrounding his Lancashire home to find out just how good this 40-yearold bike really is.
The simple answer is, very good. For a start, the bike looks magnificent. The quasi-ama Superbike styling and in-your-face red and white colour scheme still works for me after four decades. It’s not too over the top, but it is unmistakable. So, too, is the subdued rustle from the dohc engine as I wait on Martyn’s drive for the engine to warm up enough to shut off the choke knob above the top yoke. There’ll be no annoying the neighbours with the stock four-into-two exhaust.
The GS may be no lightweight at 240kg (529lb) dry, but it feels nicely balanced and manageable in traffic. The relatively long wheelbase doesn’t cause any problems as I pick my way through back streets to get out onto the moors and, once I get out onto some fast A-roads, the chassis setup really comes into its own. On fast sweepers, the bike is steadiness itself, but it’s when I get up onto the twisty moorland roads that the fun really starts.
For a physically big bike, with a bit of mass to move about, the GS changes direction remarkably well. I can see why its handling was hailed as a serious step forward for Japanese superbikes at the end of the ’70s. Flicking from side to side through a series of S-bends on Rivington Road, the big GS feels agile without any trace of skittishness. Modern tyres help, of course, but I could do this all day.
And that’s another feather in the GS1000S cap – it’s just so comfortable. Martyn rode his to the south of France back in the day and I’d be quite happy to do the same today. A broad, supportive seat, flat, wide-ish ’bars and the footrests ever so slightly rear set – pretty much in line with the swingarm spindle – makes the riding position just about perfect.
But if it’s the rolling chassis that eased the GS1000S in front of its competitors back in 1979, the engine deserves considerable credit, too. It’s a belter. It’ll pull from nothing, which is perfect in town, but it’s the midrange grunt that makes the GS so much fun – and so relaxing – to ride. Open up the tap at anything over 2500rpm and the big Suzuki gathers pace relentlessly. It’s great for storming past dawdling cars or blasting uphill through the moors. But keep the throttle pinned and there’s even more to come. Around 6500rpm the healthy midrange urge becomes a serious hit of top-end power and the GS hurls itself forward like a (rather large) greyhound out of the traps. Make no mistake, this is still a fast bike, even after 40 years.
If there’s any downside to the GS1000S, it’s the brakes. They’re not bad by 1979 standards, it’s just that we’ve all become spoiled by advances in brake technology. They need a good heave to haul up what is some fairly heavy metal, but with a firm squeeze and a bit of common sense they’re just about up to the job.
Overall, though, I’d say that the GS1000S delivers exactly what owner Martyn Kenyon hoped it would. It’s a classic bike that can be treated like a modern machine – now that Martyn and Steve have spent a winter carefully restoring it to tip-top roadworthiness. It should be good for many more thousands of miles with just routine servicing. That’s pretty impressive for a 40-year-old classic and Martyn can get on with just enjoying the ride. And, having had a couple of hours out on the moors in the sunshine on his bike, I’m certain he will.