Although the acceleration times from 0-60 mph are fairly close, the 0-130-mph clearly shows how badly the ZX-6R has the power to continue to accelerate at high speeds while the other tail off. We were impressed with how well the R6 kept up with the new Gixxer.
At MotorcycleUSA, we have an enviable and nearly endless stream of new and improved bikes that come through our garage. This is important for two key reasons. First off, it keeps us happy; secondly, it gives us a strong base on which to provide relevant riding impressions. But as good as we may be at deciphering the feelings we get from any given bike, hard numbers are simply more objective. That's why we put more of an effort into performance testing that our so-called competitors. We run our test bikes on the dyno, we roll them on to our precise electronic scales, and we strap our high-tech Vbox to record acceleration and lap-time data. (If you read our prologue, you'd know why lap times are missing this time around.)
We've got some pretty sensitive butts around here Let's try that again. Even though our seat-of-the-pants butt-dyno is kept finely tuned by constant riding, the data that's spat out of a rear-wheel dynomometer is much more specific at pointing out details than the human brain ever could.
And there's more to dyno testing than simply stating peak power numbers. Just as important is the way in which power is delivered, especially when comparing similar machines. A casual observer may, for instance, see that the CBR600RR peaks at 102.0 horsepower and assume it is a "better" engine than the ones in the R6 and GSX-R. Au contraire, mon frere. Our crew easily determined that the CBR has a peaky, top-heavy powerband even without dyno verification, but it's abundantly clear from the graph traces just how far behind it trails the others from 0-10,000 rpm. Also, the RR doesn't make more than 40 lb-ft of torque until 10,000 rpm, whereas the ZX and GSX-R have passed that mark 2000-plus-rpm earlier.
In terms of horsepower, the mighty ZX just can't be beat. It came out on top with a peak of 107.1 hp @ 12,900 rpm. Also, note how badly the CBR and R6 get clobbered around 8500 rpm.
Also of dyno note are the two flat spots in the R6's powerband, first at 3500 rpm and then at 8000 rpm. It should be noted that the midrange hole seems a lot smaller from the seat of the Yamaha, but there's no getting around that it's making substantially less power at that point. At 8400 rpm, the R6 makes about 55 horsepower compared to the 70 ponies the big-bore ZX cranks out or the 67 horsies produce by the Gixxer 6. The torque discrepancy at that rpm is just as prevalent.
It's interesting to note that the R6's bore and stroke measurements, once the most racy of all the 600s, are now the most undersquare among the three 599cc Japanese bikes. While the CBR, GSX-R and 599cc ZX-6RR share identical 67.0 x 42.5mm figures, the R6 makes due with 65.5 x 44.5mm dimensions. This longer stroke results in higher piston speeds that tax the metallurgy of the reciprocating bits. Since Yamaha's R1 now boasts the largest bore and shortest stroke among the four-cylinder literbikes, we boldly predict the motor of the 2007 R6 will follow suit. And now that titanium valves aren't just for racebikes anymore (thanks, Suzuki!), we just might see a middleweight with a redline of 17,000 rpm by then.
Making comparisons to the Ducati is difficult because of its different engine configuration and its larger displacement. However, there's no mistaking its top-to-bottom torque advantage and its horsepower lead at any given rpm within the Duc's capabilities. However, one must keep in mind the halfway point (midrange) of its powerband is 5000 rpm, whereas it's closer to 7000 rpm for the four-cylinders.
You can talk about V-Twin torque all day long, but nothing so clearly demonstrates its advantage like this dyno chart. Note how the GSX-R has a couple of brief moments below 7000 rpm when it makes more torque than the big-bore ZX. And again, take a look at the 8500-rpm range where the ZX and GSX-R whip on the other 600s.
When it comes time to putting power to the ground, the most often referenced test is a run through the quarter-mile. You may have noticed E.T.s slightly off the pace of our 2003 runs. Though we correct the times to standard temperature and barometric pressure to keep our results as relatable as possible, this year's acceleration runs were performed during undesirable conditions. The small-town airport runway we used is located about 2500 feet above sea level and the ambient temperature exceeded 100 degrees, making the engines feel like they were breathing 5800-foot air.
Combine that with a road surface that was strewn with tar snakes and a restrictive schedule that allowed each bike just three runs, it becomes easier to see why the 2004 runs were a few tenths off the ones we made last year. Anyway, what's important is that we made the runs on all five bikes within the same hour on the same day with the same number of attempts.
To no one's surprise, the 636cc ZX-6R took the top honors with its 10.77-second pass, as you'd expect from a bike with the most power and the lightest weight. The Kawi's 0-60 time is actually a tick faster than the Gixxer Thou and matches the E.T. we set on the R1 a few months ago; however, its run to 100 mph was a full second slower. The ZX was followed fairly closely by the new GSX-R (10.92), which clearly has the healthiest powerband among the three 599cc bikes.
The sprightly Yamaha posted an 11.03-second run, just a tenth of a second behind the Suzuki, and then the Honda a further tenth in arrears. Accelerate to speeds above 80 mph and the CBR will be the last four-cylinder bike to get there. It takes the Honda 3.02 seconds to accelerate from 120 to 130 mph but the Kaw does the same feat in less than 2.5 seconds. The dreadful 11.51-second run by the Ducati truly isn't indicative of its ultimate acceleration performance. Last year our Ducati 749 ran through the quarter at 11.03 seconds, so it's obvious the weakened clutch in our '04 hindered its speed.
The extra cubic centimeters in the ZX helps it attain the quickest E.T. and the highest trap speed down the quarter-mile. A weak clutch in the Ducati really hurt its performance this year.
Weight also plays a role in acceleration, and our Intercomp electronic tells the tale. Just as the Kawasaki ZX-10R was the lightest in our recent
Superbike Smackdown, the beastly 10R's little brother also has the lightest load to pull in its class. Its 385-pound tank-empty weight just edged out the skinny R6, which scaled in at 391 pounds. Suzuki's new Gixxer was close behind at 394 pounds.
And just like the literbike comparo, the Honda proved to be the heaviest among the four-cylinder machines, 420 pounds in this case. Blame for the extra mass falls primarily on the extra metal used in Honda's Unit Pro-Link rear suspension and, secondarily, on the bulk of the eye-catching underseat exhaust system. But the lardy CBR can't hold a Krispy Kreme to the 458-pound Ducati. This is the cross 749 must bear for sharing the same basic engine and chassis architecture with its 999 big brother, a machine built to withstand the rigors of World Superbike competition.
