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Our annual Supersport Shootout is one of the most fiercely contested of the year, manufacturers jockeying for top honors in the cut throat middleweight market. The 2009 version was one of the best in MotoUSA history, so when we realized that none of the bikes would be receiving any significant updates for 2010, giving us no real reason to compare them again in stock trim, well, we were pretty bummed! But only for a minute, as we came up with the idea for a totally new concept: the 2010 Modified Supersport Shootout.

We hear it all the time: If the R6 had a tuned ECU it would change the power curve; if the GSX-R had a pipe it would be lighter; if the Kawi ran shock shims it would handle better; if the Honda had nitrous it would win, and so on. Well, here it is. The four sickest 600s on the planet, all with the same modifications, the kind any educated track rider would perform, developed by the race team technicians behind many of the fastest race bikes in the USA. This is a no holds-barred middleweight slug fest where we allow a series of similar performance hop-ups to each machine, in two stages, to see how these bikes both improve individually as well as stack up against each other when it is all said and done.

2010 Honda CBR600RR2010 Kawasaki ZX-6R Comparison2010 Suzuki GSX-R600 Comparison2010 Yamaha YZF-R6 Comparison
Say hello to the 2010 Modified Supersport Shootout competitors in Stage 1 trim.

To keep the field as level as possible, both stages of the test will take place at the same two Willow Springs tracks where we did our original 2009 Middleweight Shootout – one day at Big Willow and one day at Streets of Willow. This provides us with a consistent benchmark from which to compare lap times and data throughout the process.

We also opted to do the mods in two stages as opposed to just one. Not everyone is able or willing to shell out five or six grand before ever hitting the track so we opted to start out with basic additions, get you hooked, and then you can go mortgage your house in the quest to drop that final few seconds off your lap times. Trust me, I know. (You should see my credit card bills!) Anyhow, that’s neither here nor there. Let’s get into the good stuff: The mods!

For Stage 1, each of the 600s got a full-system exhaust of the manufacturer’s choice, ECU and/or piggyback fuel management system with dyno work to match, as well as chain and sprockets to gear each bike specifically for the tracks at hand. Basic washers or spacers were allowed to be added to the shocks of the bikes to enhance the steering geometry for the racetrack, a very inexpensive and effective mod. Otherwise, everything else remained stock.

As for Stage 2, which is in the works now with the test and story to follow shortly, all four are getting Race Tech suspension front and rear, rear-sets, clip-ons, speed shifter, brake lines and brake pads, making for what will be fully-decked-out trackday machines. Short of bodywork, these bikes will be nearly race-ready after Stage 2. But for now let’s focus on Stage 1.

Just as in the stock ’09 Supersport Shootout, 3-time AMA 250cc GP champion Chuck Sorensen and myself headed up the testing duties, this time joined by fast club racer and CT Racing owner Corey Neuer plus Nip/Tuck’s John Hensley, who has been racing 600s for a little over a year now at local SoCal events.

To obtain the outright fastest lap times in the most evenly-matched and fair way possible, as we’ve been doing the past couple years, the MotoUSA Superpole system was kept in place. Chuck Sorensen and I each did an out-lap, two fliers and an in-lap on the four bikes, one at a time, all fully fueled with pre-heated, brand-new Pirelli tires. Order was drawn out of a hat and Superpole was done congruently during a 1-hour session, the outright best lap being used to compare each bike to both itself in stock form as well as the competition. The same process was followed for each of the two days, giving us data from both tracks. As for the rubber, we again used Pirelli’s DOT racing Diablo Supercorsa SC2s (see sidebar), just like we did in the original Supersport Shootout.

But enough with the details, let's get to the good stuff...


Mid-corner was probably the Suzukis strongest point and aided greatly in keeping the bike competitive.

Due to Suzuki not importing any 2010-model GSX-Rs stateside we used a brand new '09, which they put Yoshimura in charge of modifying.

For 2010 Suzuki opted not to import its GSX-R line of sportbikes to the U.S., or any street bike for that matter, instead allowing dealers time to sell the overstock of 2009s they already had. But as the ‘10 bike remained totally unchanged in the overseas markets that did get it, for our purposes a brand-new ’09 served just fine.

American Suzuki opted to hand their GSX-R600 over to tuning experts Yoshimura, as a project like this was right up their alley. Yosh installed its R-77 full titanium exhaust with carbon end can, EM-Pro ECU and engine management program with matching ignition harness, as well as its Ride Height Shim Kit for the rear shock. AFAM 520-size sprockets with an RK gold chain were installed to update the final-drive gearing, rounding out the Stage 1 changes.

On the dyno the horsepower and torque numbers of the Stage 1 Suzuki correspond similar to those of the stock bike in how it stacks up against the other unmodified machines. Horsepower is second to the Kawasaki while the torque
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output just edges the green bike for top spot, which is exactly how they are pre-modifications. The major difference is the gap between the Kawasaki and the Suzuki in terms of peak hp once modded. The stock Suzuki makes 105.15 hp compared to 105.87 hp for the Kawi, while in modified from the Kawasaki boasts 117.94 hp compared to 112.32 hp from the Suzuki – quite a gap. In terms of torque they stay very close, as the Stage 1 Kawasaki is slightly back of the updated Suzuki at 45.97 lb-ft compared 46.30 lb-ft, respectively. As for stock toque numbers, the GSX-R pumps out 43.91 lb-ft and the ZX-6R makes 42.75 lb-ft.

Another gain with the addition of a full-titanium and carbon exhaust as well as 520-sized gearing is less weight. The stock ’09 GSX-R tipped the scales at 422 lbs full of fuel, while once modified it dropped 18 lbs to roll across at a dainty 404 lbs ready to ride.

2010 Suzuki GSX-R600 Comparison2010 Suzuki GSX-R600 Comparison2010 Suzuki GSX-R600 Comparison
With the addition of Yoshimura's R-77 exhaust (middle) and EM-Pro ECU (bottom) the Suzuki put out a solid 112.32 hp and 46.30 lb-ft of torque.
How did this all translate on the track? Somewhat the opposite of how it did on paper. Several of the testers rated the Suzuki’s engine to be one of the weaker of the bunch, though at the same time the bike produced competitive lap times. This is because the GSX-R has a case of deceptive quickness. Through very precise tuning the Yosh bike has virtually no hits or spikes anywhere in the rev range, making for a seamlessly-smooth powerband, one which can easily be interpreted as ‘slow’ or ‘lacking’ even though it’s quite the opposite when you look down at the stopwatch or glance at the dyno charts.

Sorensen saw past the smooth power delivery and realized just how capable the GSX-R engine can be. “The Suzuki engine is deceivingly fast,” Sorensen comments. “While it doesn’t have a strong hit anywhere in the rev range, if you are running alongside any of the other bikes the Suzuki keeps up just fine. The power is smooth and seamless all the way through the rpms.”

When it came to the gearing the boys at Yosh guessed the best they could for both Willow tracks. Without any stock 600 data to go off of, they opted for a 15/44 combination at the big track and 15/43 at streets. While a noticeable difference over stock, the combination they ended up with was best suited to run as a five-speed at big Willow and lacked some slow-speed drive at Streets.

“The Suzuki’s gearing could have been better matched for both tracks,” continues Sorensen. “It still worked alright, though we never got into sixth at the big track and the drive out of the final corner at Streets suffered. A few teeth up at both tracks may have made a difference, which is something I’m sure they will look into for Stage 2.”

While the engine saw a split among rider opinions, the chassis definitely did not. With a low-slung seat and compact bar position, the rider sits far more “inside” the Suzuki then the rest of the current 600s, giving it a secure and planted feeling. Combined with the Yosh shock spacer that adds much-needed weight to the front of the motorcycle and the very capable Showa fork, the GSX-R’s handling was a shining point at both the uber-fast Willow Springs and the tight-and-technical Streets of Willow.

If there were any issues with the Suzuki’s suspension at all it would be the stock shock, which had a tendency to overheat and give up the ghost rather quickly, so to speak, allowing for a good deal of rear-end movement. But the GSX-
2010 Suzuki GSX-R600 Comparison2010 Suzuki GSX-R600 Comparison
The additional power and always rock-solid handling of the Suzuki made it very competitive in this group, though gearing held it back ever so slightly. Can it make up the gap in Stage 2?
R was by no means the only bike that suffered from this issue, as the Achilles heel for all the stock 600s is without question the OE shocks – some were just more vulnerable than others. The GSX-R ranked right in the middle.

“The Suzuki was probably second-quickest on turn-in behind the Yamaha and I think a lot of that comes from adding that spacer,” adds Sorensen. “It’s still very neutral while flicking left-to-right extremely easily without being twitchy like the Yamaha could be at times.”

Says Neuer: “The Suzuki is super easy to get turned in, making me very confident at all times – it really felt like it was on rails at both tracks.”

The deceptively-quick engine and solid chassis set-up translated into competitive lap times. At Willow Springs the GSX-R went third-quickest overall at 1:27.89, though only half-a-second off the class-leading Kawasaki which turned a 1:27.36. The same held true at Streets of Willow, where it finished P3 with a 1:19.61, this time less than four-tenths back of the first-place Honda which did a 1:19.27.

Comparing these times to the original shootout in stock trim from ’09, where the Suzuki did a 1:21.03 at Streets (we were unable to get times at Big Willow last year due to rain), it shows a gain of 1.42 seconds through only a few basic modifications. With the exception of the Honda, the Suzuki gained the biggest of the group on the stopwatch.

With the exception of a couple small changes, the 2010 Yamaha R6 remains virtually the same as last year. And in no way is that a bad thing. On the track the ’09 R6 proved to be a front-runner by virtue of its lightning-fast handling and amazing chassis. One area where it did require more muscle was with the engine, as the R6 demands the rider to keep it up in the rev-range for proper performance. It’s for this reason that we anticipated the added torque from an exhaust and proper gearing would benefit the Yamaha greatly.

It was no surprise to us when Yamaha sent the R6 to Graves Motorsports to have the work done. They run the factory-supported AMA teams for both Superbike and Daytona SportBike, something they have done for quite some time now in the 600cc ranks. Graves also makes its own exhausts, of which they installed a full titanium system with carbon end can. As for fueling they used the Yamaha kit ECU along with the Dynojet Power Commander 5 and Auto Tune, while gearing was also changed from 16/45 to 15/45, though they kept the stock 525 size and the OE rear sprocket and chain was retained.
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As far as weight goes, the full titanium Graves exhaust help shed 12 lbs off the already skinny R6. This takes the Yamaha’s ready-to-ride wet weight down from 409 lbs to a feathery 397 lbs, joining the Honda as one the only other bike to hit the track sub-400 lbs.

In stock form the Yamaha was one of the lower horsepower producers so when it spun the dyno at 110.63 hp @ 13,500 rpm we weren’t surprised. This put it at the back of the pack within the group, though still less than two down from the second-place Suzuki and just over half a horsepower back from the Honda in P3. Torque was along the same lines, the modified machine making 45.24 lb-ft @ 10,000 rpm. In reference to the others it’s at the bottom, though only 1.06 lb-ft off the top-producing Suzuki. As for how it compares to the stock R6, the aftermarket exhaust and accessories gained over 10 hp, as it made 100 hp before the mods, while torque grew almost 5 lb-ft, with the original bike making a mere 40.77. This is the second-largest horsepower jump of the group, just slightly behind the Honda, while it’s the single largest toque boost of the bunch.
2010 Yamaha YZF-R6 Comparison2010 Yamaha YZF-R6 Comparison2010 Yamaha YZF-R6 Comparison
The 2010 Yamaha made one of the biggest gains in power compared to stock, as Graves was able to get 110.63 hp and 45.24 lb-ft of torque form the R6.

When it came to seat-of-the-pants track testing the added oomph of the Yamaha was readily apparent, though it still demanded to be kept in the upper rev range, just as it did in stock trim. The R6 requires much more attention from the rider, as keeping it spinning over 11,000 rpm is paramount when it comes to corner-exit acceleration. Anything less and the others simply walk away. But keep it where it needs to be and the Yami feels as fast as any of the bikes here, Kawasaki excluded.

“The Yamaha engine is right there with the other bikes, though it is peakier in its delivery and you need to keep it in its happy spot – 11k to 15k,” Sorensen says of the R6. “The EXUP system (in the exhaust) works well in the lower rpm but it still does not have the torque of the Honda or the Kawasaki. This doesn’t really hurt the performance of the bike; you just have to ride it differently.”

Hensley adds that the Yamaha felt really good, but only above 13 or 14K, saying that it “is not a bad thing, this is actually a good thing, because the motor only works well at the rpm that you should be at anyway on a 600. It makes you a better rider in my eyes.”

A key element to staying in the right rev range is proper gearing, especially with the Yamaha, and was one of the areas where the R6 could have been improved. They simply dropped one tooth on the front sprocket, going from a 16/45 to 15/45, and while it translated into better acceleration compared to stock, the R6 still never used top gear around Big Willow no matter the pace. It also suffered slightly at Streets coming off some of the slower corners, as first gear wasn’t usable but second would drop the bike below 10-grand and sacrifice drive.

“Gearing could have been a bit better,” Sorensen remarks about the Yamaha. “Like the Suzuki it was a five-speed at Big Willow and at Streets it could have used a tooth or two higher out back so it wouldn’t lose so many rpm in the slower corners.”
2010 Yamaha YZF-R6 Comparison2010 Yamaha YZF-R6 Comparison
Without question the Yamaha's chassis shines during turn-in on corner entry, the effort required to change direction on the R6 almost nonexistent. Some mid-corner stability is sacrificed as a result, though. Can the suspension mods in Stage 2 remedy this altogether? Stay tuned to find out…

Proper fueling was another issue early on with the Yamaha. The on/off throttle was abrupt, making mid-corner pick-up harder than some of the others and putting added stress on the chassis. But after a call to the guys at Graves Motorsports, who did the dyno tuning, some changes were done via laptop and the bike ran night-and-day better. This goes to show just how important proper tuning is, as one can’t simply bolt on these parts and expect everything to run properly.

If there’s one area where the Yamaha really shines, and has since the R6 came out over 10 years ago, it’s initial turn-in. The aggressive geometry of the Yamaha puts a good deal of the rider’s weight up front, allowing the bike to go from side to side with extreme ease. A by-product of this in the past has been some high-speed instability, though in recent years Yamaha has done well to tune this out through a series of small updates focused on the chassis' balance. As a result the current R6 is one of the best handling bikes made: Period.

Says Sorensen: “The Yamaha clearly has the quickest turn-in. It’s the easiest bike to transition left to right, and while this may give up a bit in stability, it’s worth it. It retains good feel and feedback despite being so quick. It does feels nervous and twitchy compared to some of the other bikes, though this will not affect most experienced riders. However it may be intimidating to newer riders at first.”

Although the Yamaha may have been at the back of the pack in terms of lap times at both tracks, one must consider how extremely close all four bikes were. At Big Willow the gap between the R6 and the leading Kawasaki was a mere seven-tenths of a second, 1:28.08 compared to a 1:27.36. It was a similar story at Streets, with the Yamaha recording a 1:20.29 to Honda’s class-topping 1:19.27. That’s just over a second difference, compared to a gap of 2.7 seconds separating first from last in the original 2009 comparison.


Totally redesigned in ’07 and last updated in ’09, for this year Honda’s massively-successful CBR600RR received only color scheme changes, much like the rest of the competition. But with a track record that includes countless shootout victories, the last being in ‘08, as well as a very close second in last year’s comparison, we expected the modified Honda to be a contender. And we were right.

The boys in red don’t take these shootouts lightly and we can always tell. For this they hired none other than John Ethel to do the tuning. Ethel has a resume that dates back decades, building bikes and being a crew chief for guys like Jake Zemke and others at the highest level. He stills works with Erion Racing at some events while running his own shop, Jett Tuning, out of Camarillo, California. With years of Honda and CBR600RR tuning under his belt, Honda figured no one would be better for the job.

Ethel started off by adding a full Erion Racing Arata titanium exhaust system, including titanium end can, while the fueling duties would be handled by a Honda kit ECU and Power Commander 5 set-up & dialed-in on the Jett Tuning dyno.
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Vortex 520 sprockets and a D.I.D. Gold Chain took care of the final-drive gearing. Due to the layout of the Honda’s shock and Unit Pro-Link rear-end no spacers were able to be used, or needed for that matter. Removal of the mirrors for track duty completed the Stage 1 mods.

The updated Honda 600 spun the dyno at 111.19 hp and 45.38 lb-ft of torque. This ranked it third in modified form both in terms of horsepower and torque. As for its stock numbers, last year the Honda was last with 98.06 hp and second from the bottom with 42.35 lb-ft of torque. That solid gain of more than 13 ponies was enough to bump it up a spot and was the biggest gain in the group. The CBR’s hp now edges out the Yamaha, which makes 110.63 hp, a bike that it trailed in stock form. It also remains ahead of the Yamaha in torque output, though only slightly now – 45.39 lb-ft vs. 45.24 lb-ft, respectively. This shows the Yamaha gained more torque than the Honda, since in stock trim the difference is almost two lb-ft.
2010 Honda CBR600RR Comparison2010 Honda CBR600RR2010 Honda CBR600RR
Jett Tuning was able to muster 111.19 hp and 45.38 lb-ft of torque form the Honda. This was the biggest gain of any bike in the test compared to stock, the CBR getting 13 additional ponies form the Erion exhaust and HRC/Power Commander combination.

The stock ’09 CBR rolled across our scales at 403 lbs full of fuel, making it without question the lightest 600 of the bunch. Ditching the stock exhaust and the gearing for lighter parts only aided in its featherweight status, dropping 24 lbs to bring the wet weight down to 379 lbs, one of two bikes under 400 lbs in a ready-to-ride state and the lightest bike of the test.

Once out on the track the increased power-to-weight ratio became very apparent. Like the Suzuki the Honda is extremely smooth throughout the rev-range (just look at that graph), without inconsistencies anywhere in the power curve. Yet the CBR did feel faster seat-of-the-pants compared to the GSX-R. It’s also very consistent from top to bottom, allowing the rider to be liberal in choosing where in the rev-range he wants to ride. Of course like any 600 it prefers to be up top screaming like a banshee, but compared to a bike like the Yamaha that demands it, the Honda is far more flexible.

“The Honda engine is one of most linear bikes of the bunch, smooth and responsive all the way through the power curve, no steps or bumps,” Sorensen explains. “It doesn't feel like the most powerful against the other bikes, but I would imagine it will be right in there with the other bikes on the dyno. Also in the upper part of the rev range (12K – 16K) it has a very useable power that doesn’t sign off towards redline.”

Neuer was comfortable on the Honda right away. “The CBR was really easy to ride hard, no real dead spots in the power delivery,” he says. “It pulls strong all the way through and does so in a way that makes it very easy to exploit. Very well-tuned motorcycle.”

Honda did its homework when it came to gearing and was nearly dialed in straight off the truck. One small change was made at Big Willow, adding a tooth to the rear sprocket, after which it next to perfect. The CBR ended up with a 15-43 at the big track and a 15-46 at streets, both helped make the Honda easy to get along with.

Adds Sorensen about the gearing: “As usual Honda showed up and the gearing was nearly spot-on. I think they added maybe one tooth at Big Willow and did nothing to it at Streets and it was about as close to perfect as you can get, much like the Kawasaki was.”
2010 Honda CBR600RR2010 Honda CBR600RR
Mid-corner stability and easy-to-use power are what make the Honda such a formidable competitor. This was reflected in the lap times, the Honda at or near the front on both tracks

If I had a quarter for every time Honda showed up to a shootout with a chassis that was well sorted, well, I’d have a heavy pocket full of quarters. So, it was no surprised that the CBR hit the track solid, planted and ready to be pushed hard with few changes. That’s not to say the chassis is perfect, as it trails behind in terms of flickability, but there is no question that Honda got the absolute most from this bike.

It’s shining point? The CBR’s mid-corner stability is without reproach. Push the Honda hard through the center of any turn and it continually asks for more, a step above the rest. A good deal of this comes down to the stock rear shock, which, while not perfect, is one of the best of the group. This is also without the addition of any of the spacers or shims that some of the competition used as the stock Honda rear end doesn’t allow for it.

“The Honda has the best mid-corner stability of all the bikes,” continues Sorensen. “It’s a very taught and solid feel when planted into the corner; very responsive and confidence inspiring. The Honda shock worked very well and was one of the best. It was set up firm with very little squat under hard acceleration and seemed to soak up bumps when hard on the gas with very little fade during long runs.”

This combination of mods added up to a bike capable of some seriously quick lap times. Second-fastest to the high-horsepower Kawasaki at the big track, the CBR flashed across the stripe with a best of 1:27.75 in Superpole, just under four tenths back. At Streets the role was reversed, the Honda outpacing the Kawasaki by virtue of 1:19.27 to 1:19.56 for top spot. Averaging the two the Kawasaki takes the overall honors, though by less than a tenth of a second. Also consider this: Both bikes rated nearly equal in chassis and had the best gearing for each track, but in modified form the Honda makes almost seven horsepower less than the Kawasaki, though tips the scale 20 lbs lighter, showing that weight can be just as important as power.

Compared to times from the original Supersport Shootout in stock trim, where it was at the back of the pack with a 1:21.97, the 600RR took the biggest step forward of any machine here, shaving off a whopping 2.7 seconds around Streets of Willow. That’s a serious gain in time, displaying just how important proper gearing and a better power-to-weight ratio can be.

MotoUSA’s reigning Supersport Shootout champion comes into this comparison as the odds-on favorite. With no changes for ’10 with the exception of the BNG (Bold New Graphics) treatment (you had to know that was coming somewhere in this story…), the Kawasaki started with a target on its back, and for good reason. Not only does it make the most power out of the box, but it was also quickest in our ’09 Superpole session and picked almost unanimously by all testers in last year’s comparison. With ex-factory racing mechanic Joey Lombardo building the modified ZX-6R in house at Kawi, we suspected big things would be the result. Were they ever…

For Stage 1 Team Green aimed to source the majority of the go-fast parts from in the Kawasaki Performance Parts catalog. They opted for a Leo Vince SBK Corsa titanium full exhaust with titanium and carbon end can, while a Kawasaki kit adjustable ECU and wiring harness adapter where put in place and tuned to match the exhaust. As for gearing, the ZX-6R comes from the factory with a 520 chain. All Lombardo had to do was get new sprockets, those coming from
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Catch the Kawasaki ZX-6R in the flesh in the video portion of Stage 1 of the Modified Supersport Shootout.
Drive Systems USA, the chain remained stock. With the quick addition of a shim on the rear shock to add more forward weight to the ZX and mirrors removed the Stage 1 changes were complete.

If the dyno made one thing clear it was that once derestricted the Kawasaki makes some serious power. While all three of the others where within 1-2 hp, the ZX topped the entire field by more than 5 horsepower, turning the drum to the tune of 117.94 hp – a jump of over 12 hp from the 105.87 it made in stock trim. This gain was second only to the Honda in terms of improvement, as the CBR600RR gained just over 13 hp from stock. As for torque, this was much more in line with the competition. The ZX was just shy of the class-leading Suzuki in modified form at 45.97 lb-ft compared to 46.30 lb-ft, respectively, picking up a little more than three lb-ft over the 42.75 it produced in stock trim. In fact, all four 600s were extremely close in this regard, a range of only 1.06 lb-ft separating the entire field once modified.

The ZX comes into this shootout as one of the heavier stock machines, weighing in at 422 lbs full of fuel. Removing the stock exhaust helped out its cause, shedding 15 lbs in the process. Combined with the slightly lighter sprockets the end result was a ready-to-ride wet weight of 405 lbs, which was the heaviest of the bunch by a single pound over the Suzuki.
2010 Kawasaki ZX-6R Comparison2010 Kawasaki ZX-6R Comparison2010 Kawasaki ZX-6R Comparison
With the addition of a Leo Vince exhaust and Kawasaki's kit ECU, the ZX-6R was easily the undisputed horsepower king in Stage 1, pumping out 117.94 hp and 45.97 lb-ft of torque. Sprockets were sourced from Drive Systems USA.

As expected the Kawasaki’s engine was smack-you-in-the-face apparent from the first lap out of the pits. Strong throughout the rev range, once above 12 grand the beast came to life and left everything else floundering in its wake. Also the addition of the Kawasaki kit ECU gave an additional 1500 rpm of over-rev up top, extending redline from 14,000 to 15,500, something that didn’t go unnoticed. And the ZX would pull all the way to the limiter with no signs of letting off. Compared to stock the horsepower also peaks a full 2000 rpm higher, the base bike topping out at 12,200 rpm while the Stage 1 machine peaks at 14,200 rpm. Though while the engine was no question the ZX’s crowning glory, it also caused the bike’s low point during the second day of the test, which we will get to shortly. First let’s touch on the good stuff.

“The Kawasaki has hands down the strongest motor,” Sorensen remarks. “It has all the low-end power that you would want in addition to having a strong upper-mid range and the most over-rev of any of the bikes. The power has more noticeable steps than some of the other bikes, but feels like there is more acceleration, so it’s worth it.”

Neuer’s comments reflected those of Chuck’s. “The Kawi was super strong all the way through the power curve and the map was spot on,” he adds. “It’s just plain fast, making strong and usable power from top to bottom. It’s also not only the fastest but also one of the most forgiving if you make a mistake and lose revs.”

The Kawasaki is without question king of the motor wars, but as I alluded to earlier it showed some signs of weakness on Day 2 of the shootout. During our Superpole session on Sorensen’s out-lap, already nearly at full-tilt, wide-open down the back straight, the engine completely let go, seizing a rod bearing and blowing a hole through the case the size of my fist (that’s not an exaggeration in any way). Thankfully Chuckie was on the ball and as soon as he felt a vibration pulled in the clutch.

Despite it dumping out every last drop of oil instantaneously, much of it on the rear tire, Sorensen pulled off the save of the century and didn’t go down (he’s a former AMA champ for a reason). He then pushed the bike back to the pits and as the track was cleaned Lombardo, along with help from the Suzuki and Yamaha boys, was able to get the parts switched to the back-up bike and still made it in Superpole. Amazing stuff.
2010 Kawasaki ZX-6R Comparison
Yamaha and Suzuki both chipped in right away to aid Kawasaki in getting the back-up bike ready for Superpole after the original blew a hole in the case halfway through Day 2 at Streets of Willow.

Though the question quickly arose: How could a fairly stock bike with limited modifications have such an issue? Was it the additional rpms allowed by the kit ECU? Following the shootout Kawasaki went back over the damage and claims this was from a case (or cases) of mechanical over-rev, which happens most of the time when a rider downshifts improperly, pushing the motor past redline under deceleration, something the rev-limiter is unable to stop. Kawi believes this may have happened earlier in the test at some point(s) and weakened the engine in several areas as a result, adding that it had nothing to do with the additional rpms allowed by the kit ECU.

Whether or not this is the cause we have no way of knowing for sure. One thing worth taking into consideration in Kawasaki’s defense is that the horsepower and torque numbers you see here are from the back-up bike, as the dyno runs were performed following the track portion of the shootout. This shows that any new 2010 Kawasaki ZX-6R would more than likely be capable of these horsepower gains, and that the engine’s malfunction may have merely been a fluke. But we will let you be the judge.

One thing that was for sure was the Kawasaki’s well-sorted final-drive gearing. The 15/45 combination worked extremely efficiently at both tracks, providing good drives off the slower corners at Streets and easily pulling top gear down both the back and front straights at Big Willow. Much like the Honda, the ZX’s gearing was head and shoulders above the other two without making a single change at either track.

“Both the Kawasaki and the Honda were geared exactly where they needed to be,” says Sorensen. “The Yamaha and the Suzuki both ran five-speeds at the big track whereas the CBR and ZX would pull top gear without problem. Same held true for streets, as the ZX worked well everywhere and wasn’t between gears at all.”
2010 Kawasaki ZX-6R Comparison
Showa's Big Piston Fork on the front of the Kawasaki continued to receive praise on corner entry and mid-corner, though the bike's limiting factor is without question the stock shock.

Handling was a much improved area over its ’08 predecessor, thanks to the addition of Showa’s Big Piston Fork. This aided in corner entry and handling overall, though the ZX’s stock rear shock has always been a point of contention and weakness for the green machine – and the current bike is no exception. While one can push extremely hard going on the brakes, mid-corner and exit is limited by the rear end as one can only tune it to a certain extent without hampering the bikes abilities in other areas, making for a constant compromise, more so than some of the competition.

“I give the Kawi fork a high rating not just because of the feedback you get from it but also for the excellent adjustability you have in the settings, and that you can notice the differences when you change the clickers even the smallest amount,” says Sorensen. “Kawi used higher quality internals for this fork and it shows. Eventually the other manufacturers will apply the same thinking.”

As for the shock, Sorensen adds: “The rear moved around a bit more than some of the other bikes and was one of the limiting factors for the Kawasaki.” Neuer was on the same page, commenting that the "shock need a bit more preload or something, it was sketchy at the big track; lots of movement in Turn 5.”

2010 Kawasaki ZX-6R Comparison2010 Honda CBR600RR
With the exception of its strange engine issue on Day 2 of the comparison, so far the Kawasaki (above) and Honda have stood out as the front running pair so far.
Even without being able to get the shock perfectly set up, at Big Willow where motor is king, the Kawasaki came out on top with a best time of 1:27.36, four tenths ahead of the second-place Honda, which did a 1:27.75. As for Streets, the top two switched spots, with the Honda taking honors in front of the Kawi, 1:19.27 to 1:19.56, respectively. Averaging the two shows the Kawasaki just edges the Honda overall, though by less than a tenth of a second. Also consider that the bike which was ridden in Superpole at Streets was the back-up bike due to the first blowing up, on which no previous set-up had been done.

In regards to how it compares to last year in stock form the Kawasaki made one of the smallest gains in terms of outright lap times at Streets, dropping from a 1:20.23 (which was the fastest of the ‘09 test) to said 1:19.56, a gain of just under seven tenths of a second. This is still a formidable gain, however, especially considering how good the bike is in stock from. It did win last year’s shootout.

While this is only the first stage of our Modified Supersport Shootout and we won’t be determining a winner until all is said and done, one thing has become extremely clear – the more modifications we add the closer these bikes get. With the exception of the Kawi’s hp numbers, all the bikes spun the dyno within a couple hp. On track things were even closer, as the gap in lap times at Big Willow was just over seven tenths of a second and at Streets it was a hair over one second. This compares to a gap of almost 1.8 seconds at Streets during the stock shootout last year.

From here the bikes get upgrades to the suspension and brakes, plus a speed shifter, rear-sets and clip-ons, turning each of them into full-fledged trackday weapons. The Kawasaki and Honda proved strong so far but will the addition of more mods help put the Suzuki and Yamaha pull back into contention? Or will the gap get even larger? Stay tuned for Stage 2 to find out.