Open Warfare

OPEN WARFARE

SUZUKI GSX-R1100 AGAINS YAMAHA FZR1000 IN A BATTLE OF THE BIG-BORE REPLIRACERS

OH, H0W THE MIGHTY HAVE BEEN FORGOTTEN! SOMEHOW LOST IN All. THE HOOPLA AND EXCITEMENT surrounding the recent arrival of 900cc sportbikes is a pair of Open-class performance leaders, the Suzuki GSX-R1100 and the Yamaha FZR1000. No doubt the 900 formula that has given us the Honda CBR900RR. the Ducati 916 and the Kawasaki ZX-9 delivers a superb balance of power to weight, but the additional performance boost that liter-plus sportbikes offer throughout the power curve still holds high appeal for those of us who live for maximum two-wheeled rush. While smaller and lighter may equate to better handling on a tight or unfamiliar stretch of twisties, nothing quite matches the smooth, rhythmic experience of working a torque-strong big-bore up a zig-zag mountain grade. Roll into the throttle at any rpm and you are rewarded with rheostatic response and tractor-like grunt. Bend fluidly into a mediumto high-speed curve and the added length of wheelbase gives a feeling of rock-solid chassis stability. If you ride in a region were desolate stretches of open highway encourage sustained high-speed running, you'll quickly understand why Open-class sport-touring remains a favorite European pastime.

CW COMPARISON

While Yamaha's FZRI000, a past Cvck' World favorite in our annual Ten Best Bikes voting, returns for `95 with just a new graphics treatment, Suzuki put a good deal of effort into improving the power-to-weight ratio of its GSX-Rl 100. The main changes involve improved midrange and high-rpm power delivery, and a weight reduction of 12 pounds com pared to last year's bike. Power improvements came via use of revised valve-timing specifications (less valve overlap and a reduction in exhaust-valve lift) and a retuned exhaust system.

Both bikes are powered by liquid-cooled inline-Fours with live-speed gearboxes, beyond that the similarities are few. Suzuki's 1074cc motor has a 75.5mm bore and 60.0mm stroke, with a 11 .2: 1 compression ratio. The Yamaha also has a 75.5mm bore, but the FZR's stroke is shorter at 56.0mm, giving a displacement of 1003cc, and its 12.0:1 compression ratio is notably higher. Both engines feature dohc with centrally located cam-drive chains. The GSX-R has four valves per cylinder; the FZR employs three intake valves and two exhaust for a total of five per cylinder. The FZR's Genesis engine design incorporates a forward-angled cylinder block for a lower center of gravity while enabling the use of downdraft carburetors, straightened intake tracts and a large-volume airbox located under the front of the fuel tank. Suzuki's relatively straight-up cylinder bank mates to a conventional air box/carburetor arrangement.

The FZR's 4-into-i exhaust system incorporates Yamaha's EXUP exhaust powervalve for an increase in low-end power. Suzuki follows a different path with the GSX-R's unique 4-2-1-2 system, in which the majority of the exhaust gas exits the right muffler while the left muffler is used to maintain the correct amount of exhaust gas pres sure and minimize noise levels. A reduction in headpipe wall thickness and the use of aluminum canisters has reduced overall weight of the system.

Further steps taken by Suzuki engineers to reduce weight include changing the engine's breather cover, valve cover and signal-generator cover from aluminum to magnesium. Cooling-system pipes and lower engine-mount spacers, pre viously made of steel, arc now aluminum. Several chassis revisions have also contributed to the GSX-R's weight loss: The aluminum frame is claimed not only to be lighter, but have a 26-percent increase in torsional strength. A new, "bridged-type" swingarm is identical in design to that of the GSX-R750 but 2.1 inches longer; the swingarm-pivot shaft has been increased in diameter from 20mm to 25mm to fur ther limit flex.

Although the GSX-R's fully adjustable KYB inverted car tridge fork now has larger-diameter tubes measuring a stout 43 mm, weight has been shaved through use of thinner-wall inner and outer tubes. Triple-clamps have undergone addi tional machining of unnecessary weight. The fork's internal calibrations have been altered with a softer spring-due to the bike's weight reduction-and an increase in both rebound damping and oil level. Spring rate remains the same at the rear, while rebound damping has been decreased and compression damping firmed up a bit.

Lighter straight-spoke wheels sourced from the GSXR750 carry Dunlop’s new Sportmax II radiais. The FZR also rolls on Dunlop radiais, but of the older K510 variety. Both bikes have 17-inch wheels measuring 5.5 inches wide at the rear, 3.5 inches up front. Also common to both is the use of six-piston front-brake calipers and large-diameter floating stainless-steel rotors. While both brake systems provided all the stopping power tire grip would allow, the Suzuki’s delivered better feedback and feel through the lever. The case was the same at the back, with the FZR more prone to locking the rear wheel in a panic stop. Even so, the brake performance numbers for each bike were very close from both 30 and 60 mph.

The same cannot be said for our runs down the quartermile. When it comes to standing-start sprints, Suzuki has shot itself in the foot, hobbling the 1100 with politically corrected first-gear power output: Ignition timing is remapped whenever low gear is selected, dropping horsepower noticeably. Even with the most aggressive dragstrip launch, wheelspin was less a concern than bogging off the line. For drag-racing and roadrace starts, the system is easily defeated, though. Simply unplugging what we'll refer to as a “wheelie wire” located on one of the ignitor unit’s connector plugs restores full first-gear power, at the expense of making the Suzuki very tricky to launch-it was either wheelie or wheelspin. At the dragstrip we made several runs with the wire connected, the best of which was 10.79 seconds at 131.38 mph. Pulling the wire saw the Gixxer’s ETs drop three-tenths of a second to 10.48 (at 133.33 mph). Good enough to just nip the Yamaha’s best of 10.52 at 131.96 mph.

Before heading to Willow Springs Raceway for fast laps around the newly paved 2.5-mile road course, we had Erion Racing in Santa Ana, California, mount fresh Bridgestone Battlax BT-52 radiais on both bikes. The race-compound SS Type 4 rears and Type 3 fronts proved well up to the task of Willow’s high speeds and hard cornering loads.

If dragstrip performance was tight, lap times at Willow were virtually identical. The Yamaha’s best time was 1:30.14, the Suzuki was a nanosecond behind at 1:30.16-a dead-heat.

Looking closer for differences, we gathered split times and set up a radar speed trap at the end of the front straight. The split times divided the track into two parts, Turn 1 to 6 and Turn 6 on around to Turn 1. The first split placed emphasis on braking and handling in slowto mediumspeed corners. Here, the Suzuki felt lighter in side-to-side transitions, helping it to post a best of 49.82 seconds compared to the Yamaha’s 49.93 showing-still very, very close. Cornering clearance was slightly better on the Suzuki, although both bikes frequently ground their footpegs and occasionally planted a muffler into the road surface.

The FZR’s superior chassis stability proved beneficial in the second split, the faster section of the course, as it logged a best time of 40.14 seconds and a best trap speed of 147 mph. The GSX-R suffered from a light pogo action in the rear through fast curves and from a fairly pronounced frontend weave when pushed deep into Turn 9. Even so, the big Suzuki managed a best T6-T1 split of 40.34 seconds, registering several 145-mph passes on the radar gun. Although the two bikes were very close in time and speed, both test riders agreed that the Yamaha was easier to throw a leg over and immediately get up to speed, while the chassis movement experienced when the Suzuki was pushed near its limits took some getting used to.

On the street, the gap separating the two remained almost infinitesimal. The Suzuki is the king of midrange power; the FZR delivers an almost electric smoothness. While neither offers a plush sport-touring ride, setting either’s suspension on the soft side delivers an acceptable freeway ride. Both offer decent saddles and spacious rider accommodations (for repli-racers). Engine vibration levels are greater on the GSXR but never an annoyance. The FZR remains turbine-smooth until revved beyond 6000 rpm, where the bars and pegs begin to tingle increasingly with rpm. The Suzuki exhibits cold-bloodedness on start-up and has a bit of engine surge between 3000 and 4000 rpm even when fully warm. Enriching the GSX-R’s fuel-mixture screws would likely cure the lean condition. The FZR displayed no such carburetion anomalies.

So where does all this leave us? Never before have we had such a toss-up based on the performance numbers-mere fractions of a second separate the two at both road course and dragstrip (at least after the Suzuki was de-wired). In outright top-speed passes, both bikes ripped the wind at an identical 162 mph. Back-toback street rides didn't help. Each has its own on-road identity, but there is no clear-cut advantage either way. If you’re on a budget, the FZR’s $250less-expensive sticker may hold some sway, but then again if you’re a penny-pincher you probably wouldn’t be looking at $9000-plus motorcycles in the first place.

In the end, then, it’s simply too close to call; we have no outright winner here. We do know this, though: If you’re in the market for repli-racer styling, razor’s-edge handling and the soul-stirring wallop of a full 1 OOOcc-plus, your options are exactly two.

And you won't go wrong with either one. E3

SUZUKI GSX-R1100

$9549

YAMAHA FZR1000

$9299