Yoshimura Formula Usa 1100
YOSHIMURA FORMULA USA 1100
GSX-R
RIDING IMPRESSION
We ride Scott Gray's unlimited-class GSX-R1100 and discover why roadracing has rules
IMAGINE WHAT ROADRACING WOULD BE LIKE IF IT HAD no limits. Imagine the kinds of bikes that would roll onto the starting grid if there were no rules restricting displacement, horsepower, weight or mechanical equipment. Such a class of racing would give rise to bikes that were incredibly exotic, astonishingly powerful and, most of all, outrageously fast.
Well, believe it or not, that kind of no-holds-barred racing actually does exist—on the West Coast, at least. It’s called the Formula USA series, and was conceived by Bill and Chris Huth, operators of Willow Springs Raceway in Rosamond, California. To enter, a motorcycle simply has to have two wheels and not be a track hazard. Other than that, there are, basically, no rules.
This season, that six-race series was won by Scott Gray aboard a fire-breathing monster of a racebike, a 160horsepower, 350-pound Suzuki GSX-R1100 built by Yoshimura. And after a full day of riding Gray’s machine at Willow Springs, we can assure you that it is everything your imagination thinks it ought to be—and perhaps more. It’s an extreme, the likes of which haven’t been seen since the days of the Formula One class at Daytona, when racebikes like the Yamaha OW69 and Honda FWS1000 took horsepower outputs to new highs.
What’s surprising is that Gray’s 1 100 isn’t all that exotic or hard to duplicate. Its engine is virtually the same GSXR1100 powerplant used in Yoshimura’s 1100 Tornado streetbike, save for a close-ratio six-speed gearbox and a less-restrictive exhaust system. The chassis replicates the one on Kevin Schwantz’s 750 Superbike, and the whole works is topped off with the Tornado bodywork. The end result is the most formidable motorcycle currently racing in the United States. And practically all its engine components came from Yoshimura’s stock of for-sale parts and accessories.
Now, you might argue that 160 bhp isn’t all that much in these days of 500cc two-stroke GP racebikes that produce similar horsepower numbers and weigh less. But what’s so impressive about the power of the Yoshimura 1 100 is that it’s not confined to a 1 500or 2000-rpm-wide powerband like on the GP machines; instead, the Yosh bike makes awesome power everywhere. It cranks out over 100 horsepower at 6000 rpm. which is barely halfway to the engine’s 1 1,000-rpm redline. It begins accelerating as hard as most big-bore streetbikes at a mere 3000 rpm, and will wheelie out of some corners at as little as 4000 rpm. And from around 8500 or 9000 rpm up to redline you’d better hang on, because the bike accelerates like the Enterprise after Captain Kirk calls down to the engine room for Warp Eight.
What’s more. Gray's racer accelerates like that just about all the time, no matter w hat gear it’s in. All the way down Willow’s long front straight, it never stopped pulling hard. It made the football-field-long straight between high-speed Turn Eight and very fast Turn Nine seem more like a short driveway. If the rider didn't make a conscious effort to avoid doing so. he would find himself wheelieing out of high-speed turns One. Tw o and Nine, up the hill out of Turn Three, and over the rise of Turn Six. The rear Michelin radial slick offered unbelievable traction, but the engine could still spin it and slide the rear end if the rider didn't use the throttle judiciously.
Amazingly enough, though, the bike is not all that hard to operate once the rider learns a few basic rules. Rule Two is. never wdiack the throttle open; gently roll it on. Rule Three is, when in doubt, upshift; at lower rpm. impressive things still happen, but they happen a little more slowly. Once, one of our staffers even left the 1 100 in sixth gear all the w'ay around the track and still posted a respectable lap time.
What’s Rule One, you ask? Well, the very first thing anyone needs to do on this bike is to learn how to use the brakes to their limit. Because the first time you dump the throttle wide-open and are catapulted down the straightaway at lightspeed. you find that the next corner sneaks up on you faster than you ever thought possible, and all you can think about at that point is grabbing all the brakes you can find.
Once those rules are firmlv etched in the rider’s mind, Gray's 1100 is big-time fun and not all that difficult to ride, despite being a never-ending adrenaline rush on two wheels. As you might expect from a bike with a state-ofthe-art Superbike chassis, the handling is superb, aided by a dry weight of only 350 pounds—lighter even than Schwantz’s 750 because of the AMA's minimum weight limit of 392 pounds for Superbikes. On the 750. weights have been added to make the bike legal.
For our group of test riders (editors Paul Dean. Ron Lawson. David Edwards and Steve Anderson, plus tester/ racer Doug Toland), however, the suspension was too stiff. It had been set up for Gray, who weighs over 200 pounds and rides the bike hard enough to have broken Willow's motorcycle lap record by a fraction of a second. But for us. the front end would dance and skitter over the track's little chops and ripples. That problem was made even worse bv the bike's mammoth power output, which, at best, keeps the front wheel just barely skimming the ground under acceleration. Still, every one of us—even seasoned racer Toland—stepped off the Yoshimura 1 100 with impressions in our minds that won’t soon be forgotten. and smiles on our faces that won't soon be wiped off And most of us had circulated the track seconds faster than we ever had before.
All things considered, though. Yoshimura's Formula USA bike is nowhere near as exotic as it could be. as radical as the rules would allow it to be. So liberal is the class that Formula USA bikes could even run nitrous and be turbocharged. But Gray thinks that hot-rodding of that sort would hurt more than help. He firmlv believes that a roadrace bike can onlv produce so much horsepower before its power becomes a disadvantage, and that the Yoshimura GSX-R1100 already has as much power as anyone really needs.
After a day on the beast, we definitely astree. 0
