The Polen Poll
THE POLEN POLL
The best production roadracer in America picks the best 600cc production roadracer in America
DAVID EDWARDS
The Premise:
Since competition is so intense in 600cc production-class roadracing, and since a winner on the racetrack is usually a winner in the showroom, we would set-up the four class contenders for 1988—the Yamaha FZ600, the Kawasaki Ninja 600, the Honda Hurricane 600 and the Suzuki Katana 600—according to production-racing rules, bring in the most accomplished rider possible who could evaluate the bikes at winning race speeds, and find out which machine will make the year’s best 600cc production roadracer.
The Rider:
Doug Polen, 27, of Denton, Texas, perhaps the foremost racer of production motorcycles in the world. He made headlines in 1986 when he traveled the country, hitting as many local races as possible, taking home $90,000 in prize and contingency money (“Club Roadracing’s Professional Amateur,” Clf, May 1987). Last year, his season winnings ran well into six figures, and he came home with Suzuki GSX-R Cup national titles in both the 750 and 1 lOOcc classes. He also dominated the inaugural 600cc Supersport Series, riding a Hurricane 600, with eight wins in the nine-race campaign. He set class lap records at tracks all over the U.S., including five outright motorcycle lap records, all on bikes riding on DOT-approved tires and with little more than engine blueprinting and aftermarket suspension components. Polen also contested the AMA Superbike series, finishing fourth in the overall standings.
The Set-Ups:
Tires and suspensions that work well on the street just aren’t up to the demands of racing—not, at least, if you have serious thoughts of winning. That's why almost no one, even in production classes, races a completely stock motorcycle. So, our first modification was a change in rubber.
Almost all of the major tire companies offer a track version of their latest high-performance street tires. Although DOT-approved and fully street-legal, these tires are more or less slicks with tread, and offer phenomenal traction. For this comparison, we mounted Dunlop’s new K591R production-racing tires on all four motorcycles. Besides being state-of-the-art, these are tires that Polen helped to develop, and the tires he used to win his championships last year. Prices for the front 591Rs we used range from $94 to $99, depending on rim size and width, with the rears costing from $ 1 1 8 to $ 138. These R-series tires, as well as the more-streetable K591S versions, are available at motorcycle shops everywhere. If you need more information, contact Dunlop at PO. Box 1 109, Buffalo, NY 14240; (716) 773-8224.
Our next call was to the Fox Factory, makers of Fox Racing Shox, the dampers Polen used on the rear of his Suzukis and Hondas last year. Fox sent us four of its Twin Clickers, which are high-quality, reservoir-equipped shock units adjustable for both rebound and compression damping. Besides upping racetrack performance, the Twin Clickers are such beautifully made pieces that it’s a crime to hide them away behind frame tubes and plastic sidepanels. Available either from motorcycle shops or direct from the Fox Factory (544 McGlincey Lane, Campbell, CA 95008; [408] 377-3422), the Twin Clickers retail for $395 with springs ($350 for the Honda unit, which uses the stock spring).
With the rear suspensions fortified for racing, the front forks needed some equalizing. Progressive Suspension (11129 Ave. G, Hesperia, CA 92345; [619] 948-4012) solved the problem with four of its $55.95 spring kits. These are the same progressively wound springs that the company sells for streetbike applications; we just used longer preload spacers to firm things up. The Progressive springs are available through motorcycle shops and come with a lifetime guarantee against defects and sacking.
With identical tires and comparable suspensions installed on our test 600s, it was now possible for Polen to concentrate on determining which bike had the best power and handling. Had we really been racing, turn signals, mirrors and sidestands would have had to been removed. In addition, serious class contenders would also do what little hot-rodding is allowed under production-racing rules: things like lmm-over cylinder bores, carburetor rejetting and installation of brake pads with higher coefficients of friction.
The Place:
Willow Springs Raceway, a nine-turn, 2.5-mile racetrack in Southern California’s high desert. Polen owns the 600cc Production lap record at Willow; 1 minute, 31.6 seconds, set last year on his Hurricane. Also on hand for the test, besides Polen and members of the Cycle World staff, were David Buck, Dunlop’s chief motorcycle tire engineer; Mark Matzinger, Dunlop's West Coast racing distributor; Jerry Castillo from the Fox Factory; and Larry Langley and Mike Henderson from Progressive Suspension.
The Results:
Polen rode each motorcycle three different times, with the first two sessions being used to dial-in the suspensions. For the final session, each 600 was treated to a fresh rear tire. You’ll notice, however, that two of the bikes turned quicker lap times during their earlier sessions. This was because the ambient temperature and, hence, the tracksurface temperature dropped dramatically just before the final session, decreasing traction. What follows is Polen’s ranking of each machine as a production roadracer, with lap times and his comments.
The Yamaha:
The FZ600 nailed down last place in Polen’s poll, a bit surprising, seeing as how the Yamaha has been almost unanimously acclaimed as the best-handling sportbike in America. As a racebike, though, the Yamaha is handicapped by its engine. With the only air-cooled powerplant among these 600s, the FZ gives away something like 15 horsepower to its competitors. As Polen so bluntly put it, “It didn’t have any power to speak of.”
Neither was he impressed by some of the bike's handling characteristics. “I think there’s something in the design of the rear suspension that’s causing a problem. It was very stiff; sometimes it felt like it would chatter right out from under me. It definitely didn’t lend any confidence. We tried several different settings, all over the suspensiontuning realm, and it did the same thing, no matter what.” The Yamaha’s brakes didn’t avoid Polen’s scrutiny, either. “It’s got the worst front brakes of the whole lot,” he said. “In the end, I could get it to stop, but I had to pull hard, really hard on the lever. During a race, I wouldn't want to go that last 10 or 20 feet into a corner and latebrake; the brakes just aren’t consistent enough for that.” Still, Polen did have some good to say about the Yamaha. “The precision of the steering is really good. I liked that a lot. When I wanted to go somewhere, it just went. It does have problems, but that’s not to say that there isn’t some track somewhere in these United States that wouldn’t fit the Yamaha like a glove.”
Apparently, Willow Springs isn't that track, however. Because even though the FZ actually turned in the thirdfastest lap time of the day—a 1:36.57 during the set-up period-its 1:38.68 in the final test session was almost two full seconds behind that session’s third-place finisher.
The Kawasaki:
Polen's summation of the Ninja 600, his third-ranked 600cc production racer, was mixed. “It's definitely up on power, but down on handling, especially the front end. It’s got the best powerband of all the bikes. It would come on early and pull real hard all the way to redline. It’s got really good brakes, and the rear suspension was fine. The bike was just limited by its front-end capabilities.”
Elaborating on the problem, Polen said: “The Ninja had a real strange front-end feel, and I'm not sure why. We really didn’t have enough time to figure it out. It had a real choppy feel to it; perhaps the anti-dive system was the cause of the problem. It also seemed that the geometry, with a 16-inch front wheel, was a tad quick-steering, which made the bike feel slightly twitchy. All in all, it didn’t give me the feeling of wanting to hang it out, of wanting to push it right to the edge.”
Polen’s suspicions about the Ninja’s 16-inch wheels were later verified by Walter Nitto, who races an older Ninja in the 600cc Superstreet class, where extensive modifications are allowed. “We could never make our bike work with 16-inch wheels,” said Nitto. “We could never get it to where you could trust it. Bolt on a set of 18inch wheels and the change is remarkable. Everybody who’s going fast on a Ninja uses 18-inch wheels.” Nitto knows what he’s talking about. In 1987, he and his 18inch-wheeled Ninja 600 were the Supersport champions at Willow Springs.
The 1988 Ninja’s best lap time, a 1:36.61, came in its third session; and although, overall, the FZ600 just edged out the Ninja for third-best time, during that third and final test session, the Kawasaki was consistently two seconds a lap quicker than the Yamaha.
The Honda:
Polen had never ridden an FZ600, Ninja or Katana before this test, and so, of course, felt more at-home on the Hurricane, a bike he logged thousands of track miles on last year. That confidence was quickly demonstrated when Polen set what would turn out to be the quickest lap time of the day on the Honda during his second ride on the bike. His 1:33.69 was just two seconds slower than his best-ever 600cc race time at Willow.
Yet, during the colder final test session, after all the suspensions had been dialed-in and fresh rear tires mounted, Polen could post no better than a 1:35.04, eighttenths of a second behind the Suzuki Katana. Although he felt the Honda pulled more strongly though its powerband than the Katana, he eventually rated the Honda as secondbest 600cc production racer by virtue of a slight handling deficiency that makes itself known in high-speed corners. “There, the Honda’s steering has a strange feeling, like it wants to tuck the front end. Essentially, this bike is set-up just the same as my race Hurricane, and that does the same thing. I didn't get that feeling on the Suzuki: It was rocksolid. It seems like there’s something a shade off with the Honda as far as rake and trail and weight-bias. It seems as if it ‘works’ the front end more than the Suzuki.”
Polen also felt the Honda’s rear suspension was a notch—albeit a small one-below the Suzuki’s. “It worked well, but didn't feels as smooth all the way through its travel,” he said.
Still, Polen stressed the closeness of the Hurricane and the Katana as rivals for production racing. “It almost comes down to rider preference,” he said. “Let’s just say that if the Suzuki is a 10, then the Honda is a 9.5.”
The Suzuki:
The Katana 600, then, is the motorcycle Doug Polen chooses as the best 600cc production roadracer for 1988. His best lap time on the bike, during the final test session, was 1:34.28, the best of that session, even if it was just over a half-second slower than the Hurricane's quickest time set earlier in the day. “The Katana is very neutral-handling and has a good, smooth-acting suspension,” he said. “The power output isn’t enormous, but it has enough to get the job done.”
Told that the Katana weighed 19 pounds more than the Honda, Polen replied, “Well, I couldn’t feel the extra weight. If anything, it was easier to change direction on the Suzuki than on the Honda. So, wherever that extra weight is, it doesn’t seem to be very high.”
Summing things up, Polen said, “It comes down to this: The Honda has more power than the Suzuki, but the Suzuki handles better than the Honda. I enjoyed riding the Suzuki more than the other bikes; it didn't have any quirks. It’s just a good-feeling motorcycle. I was motivated to ride harder and harder and harder because I could concentrate on going faster without having to worry, say, about what the front end was going to do in Turn Eight.”
Of course, Polen is motivated by other things, as well. Money, for instance. And in 1988, money will be a very important factor when it comes time for racers to decide between a Honda and Suzuki. Suzuki has an extensive contingency program that pays $ 800 for a win at selected club roadraces and $1600 for a win at a 600 Supersport race. Honda, on the other hand, has dropped its contingency programs this year.
So, when the green flag drops on the first 600cc Production race of 1988, Doug Polen, the best production racer in America, will be riding a Suzuki Katana 600. 0
