Yoshimura Tornado 750 And 1100

YOSHIMURA TORNADO 750 AND 1100

GSX-R

RIDING IMPRESSION

Bringing Superbike technology (and speed) to the street

THERE IS NO HORIZON; INSTEAD, THE WORLD IS A WALL of asphalt, bending up and away out of sight. Centrifugal force shoves you down against the tank, and every bump hammers you and the bike. Filling your peripheral vision is an ugly white guard rail, rushing by at 80 yards a second, only feet from your leg. But with the throttle held on, the motorcycle howls and accelerates, and when the banking levels and straightens, more than 10,000 rpm shows on the tach. The exhaust fights the burble of the wind; only the straight ahead can be seen clearly. Trees and buildings blur past. As the bike inhales the straightaway, the tach needle moves through molasses, climbing slowly to 10,900 rpm. The speed trap rips past.

Later, the timers tell you that you were traveling 181 mph; the amazement is that the motorcycle was still accelerating when you rolled off the throttle.

Such is Yoshimura’s Tornado 1 100 (also called the Bonneville, but only in Japan), surely the most powerful motorcycle in any type of regular production. It and its stablemate, the 750 Tornado, bring Yoshimura’s racing expertise to bear on a streetbike. In Japan, you can buy either Tornado complete, with documents showing Yoshimura as the machine’s manufacturer. In the U.S., Yoshimura R&D will sell you all the parts needed to build either machine; you need only supply your own Suzuki GSX-R.

Either Tornado always begins life as a GSX-R. Yoshimura then begins throwing hardware away, starting with the stock front fork and rear shock. The standard wheels are trashed, along with the front brake calipers and discs. All the standard Suzuki bodywork—the fairing, gas tank and seat—are relegated to the salvage yard. By that point, all that’s really left from Suzuki is an engine and a frame.

And Yoshimura isn't done yet. The carburetors and exhaust system are scrapped, as are pistons and valves and

camshafts. It’s from the barest of GSX-R bones that a Tornado is built.

The 750 receives 1 mm-larger Yoshimura pistons (yielding 768cc), bigger valves, and camshafts with higher and longer bumps. For the 1 100, the bore increase is 2mm, raising the displacement to 1 109cc. The 1 100 gets bigger valves and wilder. Stage 2 Yoshimura cams, as well. Carburation for the 750 comes from a set of 36mm Mikuni flat-slide instruments; exhaust is either a made-inthe-USA Yoshimura R&D pipe, or a Yoshimura Japan “Cyclone” pipe for the home-market models.

From here, it’s a little hard to be certain exactly what’s standard on a 1100 Tornado. Thirty or so production 1 100 “Bonneville” Tornados will be assembled in the U.S. at Yoshimura R&D and then returned to Japan; they can then qualify as imported motorcycles not subject to Japan's 750cc displacement limit. These bikes, according to Yoshimura, will come with 34mm flat-slide Mikunis and a streetable Yoshimura Japan exhaust system. But an 1100 we sampled in Japan wore a set of works magnesium 38mm flat-slide Mikunis, along with a Yoshimura titanium exhaust system, a racing part available only on special order for more than $ 1 500.

Our conclusion from all this is that, perhaps with the exception of the 30 production bikes, no two Tornados are any more alike than any two racing Ducatis, and that it’s the bodywork that makes a Tornado; the engine can be any combination of items from the Yoshimura catalog.

The bodywork itself is a marked improvement in both style and function over the standard Suzuki parts. The aluminum Tornado gas tank is available in two versions, with or without an under-tank cutaway for an airbox. Shorter, wider and lower than a standard GSX-R tank, the 6.3-gallon (without the airbox cutaway) Tornado tank simply never intrudes on the rider, and helps make the Tornado feel smaller than a stock GSX-R. The seat and fairing are designed to be used with genuine racing-low clip-ons and Yoshimura rearsets; the Tornado’s riding position has more forward lean than a standard GSX-R. but if anything feels more natural, and is no more uncomfortable on the highway. The lightweight bodywork also helps contribute to the general lightness of these machines: The 750 Tornado, for example, weighs just 385 pounds.

As for performance, both machines have their share, and then some. The weight difference alone would give them a solid boost overa standard GSX-R; the extra horsepower (perhaps 160 at the crank for the 1 100) moves these machines into the performance outer limits. The 1 100 will pick its front wheel up on half-throttle at 4000 rpm in first gear, and it accelerates as hard at 150 mph as most literclass bikes do at 120. It’s a machine that will keep the most jaded of sportbike riders amused—at least until he loses his license.

The 750 isn’t as overwhelming as the 1 100, but it charges more like a normal literbike than a production 750. We rode the 750 Tornado at Willow Springs at the same time as Kevin Schwantz’s Superbike, and it was only a notch slower than the machine that won five Nationals last year. Perhaps most surprising with both 1 100 and 750 are the breadth of their powerbands and the quality of their carburation. While both bikes make their best power at high rpm, both also have a strong mid-range and run cleanly enough not to be annoying during street riding. That’s not something you can say about every hot-rodded engine.

Keeping all this power under control are the Yoshimura suspension and brake modifications. The new Yoshimura/ Showa fork and Yoshimura/KYB rear shock offer firm springing with good damping control, and the Nissin front calipers and Yoshimura discs are true Superbike quality; they'll stop the 1 100 from its 1 80-mph-or-so top speed without a hint of fade.

If there’s any real drawback to the Tornados other than their damage to your insurance rating, it is their cost. The 750 sells for about $16,000 in Japan; the 1 100 for about $22,000. If you want to build one yourself, you’ll need to contact Yoshimura R&D of America (4555 Carter Court, Chino, CA 91710; [714] 628-4722). But the bodywork kit alone (tank, seat, fairing, rearsets and bars) sells for almost $3000. Like any product manufactured in the Land of the Rising Yen, the Tornados cost too many of our dollars.

But, then again, where else are you going to find a 1 80mph streetbike at any price?