Was The 1993 Yamaha GTS1000 A Quantum Leap In Motorcycle Design?

This article was originally published in the February 1993 issue of Cycle World.

Consider how many genuinely new concepts there have been in motorcycle technology in the last 20 years. The list is disappointingly short. Sure, there have been significant improvements in suspension, chassis, engine, brake and tire technology over the years, but these have been evolutionary rather than revolutionary.

Now Yamaha is claiming that its latest model represents "a major leap forward in motorcycle design." Well, I've just ridden the GTS1000 at the bike's press launch in Morocco, and Yamaha isn't telling lies—the GTS is very different. Take a look at a picture of it without bodywork, and you'll see how different it is. There is no telescopic front fork and the frame is unlike anything else currently in mass-production. This is one trick motorcycle.

But why bother? Surely conventional motorcycle design is pretty well perfect these days. Grand prix machinery uses telescopic forks and conventional chassis, so why would a 100-horsepower sport-tourer need something different? A good question. The obvious answer is that the GTS's RADD-derived front-suspension system allows the steering function to be separated from the suspension, and without the need for a steering head, the frame and center of gravity can be lowered. All of which, theoretically, makes for improved handling.

The GTS wasn't designed to be the last word in handling, though, it was designed to be "technologically superior...the most sophisticated road-going Yamaha motorcycle ever produced." In the same way that Honda produced the oval-piston NR750 to prove how clever it is, Yamaha has produced the GTS to prove that it can build the ultimate high-tech sport-tourer. And they've really packed it in: single-sided front swingarm, Omega chassis, electronic fuel injection, three-way catalytic converter, anti-lock brakes, six-piston front-brake caliper.

Heart of the GTS is a modified FZR1000 motor, a dohc, 20-valve, liquid-cooled inline-Four displacing 1002cc from a bore and stroke of 75.5 x 58mm. The FZR motor has been altered to produce more low-down and midrange power primarily by fitting softer cams, lowering the compression ratio and equipping the bike with electronic fuel-injection. The benefits of EFI are many fold, but the primary ones are more efficient engine management, improved fuel consumption, adaptability to a wide range of atmospheric conditions and improved throttle response. It even eliminates the need for a choke and is self-diagnostic.

On the exhaust side, a 4-into-1 pipe features a three-way catalytic converter that is claimed to remove 60 percent of hydrocarbons, 70 percent of carbon monoxide and 70 percent of nitrogen oxides from the exhaust gasses. Unfortunately, it converts them all into carbon dioxide, a major contributor to global warming—you pay your money, you chose your pollutant. The result of this fiddling and tweaking is an engine that produces a claimed 100 horsepower at 8000 rpm, and 78 foot-pounds of torque at 6500 rpm, thus making it acceptable to the Eurocrats and their agreed-upon horsepower limits.

Around this understated, if fairly elegant, engine wraps a frame the like of which has not been seen on a mass-produced motorcycle. Called the Omega chassis (on account of its resemblance to the last letter in the Greek alphabet), it is basically a box-shaped aluminum affair that wraps around the motor, and onto which are bolted the front- and rear-suspension systems. There was no need to run the main frame-rails up to a steering head, so the frame was kept lower and smaller, and the engine positioned further forward than it would be normally.

But it's that odd-looking front end that sparks all the fuss. In recent times, the only other production bike to feature front suspension using something other than a telescopic fork was the Bimota Tesi. Bimota proved that alternate front-suspension could work. Now Yamaha has put it into mass production. If it all looks seriously complicated, that's because it is. What you have to realize is that the steering system and suspension system are completely independent of each other and work in ways totally different to those of the conventional telescopic fork (see "Omega Explored," Cycle World, December, 1992). Understand that, and spend a few minutes examining the pictures, and you'll have a pretty good idea of how it works.

The rear suspension is far more familiar, being basically a swingarm and shock from an FZR1000 bolted to the back of the Omega chassis. On a technologically advanced bike like this, a single-sided rear swingarm as used on the Honda VFR750 and Hawk GT would have looked the business, but the thought of tangling with Honda's patent lawyers probably put Yamaha off.

One of the problems inherent in front-swingarm designs is that you can only fit one brake disc. That's not a problem for something that weighs 300 pounds, but for a liter-class sportbike weighing in excess of 500 pounds, a standard disc and caliper aren't enough. To get around this, Yamaha simply fitted one massive six-pot, opposed-piston caliper, grabbing a 12.6-inch ventilated disc. A twin-piston caliper acts on a 11.1-inch disc at the rear. At the time of the press intro, there were no ABS-equipped GTS1000s yet built, but Yamaha's excellent and proven anti-lock system will be available as an option in Europe and standard in the U.S. Wheels are shod with a 130160-17 Michelin radial at the front and a 170160-17 at the back.

So, on paper it all looks pretty impressive: new front end, trick frame, modified EXUP engine, EFI, ABS, exhaust catalyst. But does the GTS actually work, and what does it feel like compared to a conventionally suspended bike? The answer is yes it does work, but it feels different from anything you've ever ridden.

From the minute you fire it up and get under way, you know that there is something abnormal about the GTS. At low speed, the steering is surprisingly light and very precise, but there's something in the way the suspension works separately from the steering that lets you know straight away that this is no ordinary bike. One surprise is the very limited turning circle. Several unwary journalists got caught out by the limited steering lock and heavy weight of the bike, and found themselves struggling to pick a 550-pound GTS off its side.

Threading through the chaos that is rush-hour traffic in downtown Marrakesh, Morocco, the GTS felt slick and capable. The riding position is comfortable and on the sporting side of upright; the handlebars are lower and slightly further forward than the FJ1200, the footpegs lower and slightly further back. The engine starts cleanly and easily, and pulls briskly from below 3000 revs to the 10,500-rpm redline. Out on the desert roads, far from the madding crowd, the GTS could be let off its leash and ridden in the manner of a sport-tourer—very fast. The engine, although restricted to 100 horsepower, is smooth and willing, blessed with an abundance of usable power and torque. It quickly became apparent that there was little point in revving it to the redline, as the GTS starts to run out of steam above 8000 rpm. This isn't a bike that oozes brute power in the same way as a ZX-11; this is refined, non-threatening, usable power. Enough power to have the GTS indicating 155 mph on a couple of occasions.

But top speed isn't really what the GTS is about. It's about sport-touring, and for that you need fine handling and lots of midrange power. Up in the foothills of the Atlas Mountains, with the desert far below, the GTS was in sport-touring territory. A variety of road conditions, from flat-out sweeping curves to first-gear hairpin bends, was a real test of the GTS, and it did pretty well. The motor, especially between 5000 and 8000 rpm, is a beauty, with bags of power and torque that enable you to storm along at an impressive rate. No need to make too much use of the slick, five-speed gearbox, just crack open the throttle and away you go, the efficient EFI delivering exactly the right mix of fuel and air at all engine speeds and loads.

If the steering at low speeds felt precise and neutral, at higher speeds it started to feel quite strange. There is a distinct reluctance to turn into a corner, and to get the GTS to turn-in requires more physical effort than you might expect. Once you've overcome that initial reluctance, however, the GTS can be picked up or leaned farther with much less effort. The steering geometry itself is nothing out of the ordinary (24 degrees of rake and 4.0 inches of trail), but the relative heaviness of the bike and its long, 58.9-inch wheelbase make it hard work to flick through tight turns. It is precisely that weight and wheelbase, however, that make it rock-steady at 150 mph.

The other thing I found unsettling about the GTS was that once cranked into a turn, I wasn't at all sure what was going on beneath me. When you've spent your life riding motorcycles with a telescopic front fork, you pick up data from the bike and react accordingly. With the GTS, the signals are different, unfamiliar. Part of the problem, if you can call it a problem, is that the handlebars seem very remote from that contact patch between the front tire and the road. There's an awful lot of metalwork and ball-joints between the two, and with the suspension working independent of the steering, the whole feeling is one of isolation. You soon get accustomed to the different sensations—I was beginning to get the hang of it after a day in the saddle—but it can be a little unnerving at first.

Despite the slight vagueness of the front end, the suspension worked very well, and it is something of a revelation to be able to trail the brakes right to the apex of a turn without upsetting the suspension and steering. Demonic late-braking maneuvers are a piece of cake, even considering the weight of the GTS. And the brakes are very good, although the lack of front-end dive when hard on the front disc is another curious sensation of the RADD system.

But if the handling and braking takes a bit of getting used to, the GTS is easy and familiar in every other respect. The riding position is perfect for sport-touring, and the spacious saddle is still comfortable after 10 hours on the road. The fairing is also impressive, effectively diverting air from the rider.

The instrumentation is of a commendably high standard, with fuel gauge, twin tripmeters, digital clock and all the usual idiot lights. The ignition switch is a hardened seven-leaf tumbler that Yamaha claims is drill-resistant. For additional theft protection, any attempt to bypass the ignition switch will trip an automatic cut-out in the fuel-injection system. There is also a box under the seat specially designed to accept a shackle lock, and a small glove compartment on top of the fuel tank that is large enough for a pair of sunglasses and a pack of cigarettes. If you need more storage space than that, two different sizes of saddlebags will be available as options, which should enhance the GTS as a sport-tourer.

Unfortunately for long-distance types, the fuel tank holds 5.2 gallons, not a whole lot for a bike that could easily cover 300 miles without the need to stop. As it is, assuming fuel consumption in the region of 40 miles to the gallon, you'll be lucky to get much farther than 200 miles between fill-ups. Another gallon and a half would make all the difference.

Styling? Well, the GTS certainly looks unusual, but attractive it isn't. If it was considerably more futuristic, like the Morpho concept bike that Yamaha has been taking around the bike shows for the last couple of years, it would be a lot more appealing. As it is, it looks too much like a ZX-11 or CBR1000 with a funny front end. At least the bodywork is not covered in garish graphics and painted vulgar colors.

All in all, I would say that the GTS1000 is a pretty good bike, though for around $13,000, it should be. It exudes class and style, and with its optional hard bags, should be an accomplished sport-tourer. The front end takes some getting used to, but it seems to work well, and the engine is smooth and capable. Apart from the front-swingarm suspension, the GTS is really fairly unremarkable in every way—except for the price. And it's here that it may experience a few problems. For the same money, you can buy almost anything on two wheels, from a full-dress tourer to a state-of-the-art sport-bike. Sure, it's classy and exclusive, but it's really no better than a ZX-11, a CBR1000 or any other liter-sized sport-tourer. What you're paying for is a fancy front end. If you like it, that's fine; if you don't, then it's not.

With the new Yamaha GTS1000, that's the question.