Motorcycle News
07-24-2008, 05:28 AM
Kawasaki ZX-RR 800 - Less Mean Greenie
http://images.sportrider.com/features/146_0805_01_z+kawasaki_ZX-RR_800+three_quarter_view.jpgIt was all change for Kawasaki's MotoGP effort in 2007, with the previously European-run race team put under the direct factory control of experienced Grand Prix stalwart Ichiro Yoda. The team's European base moved to Holland from Germany, and an all-new motorcycle, the ZX-RR 800, was created for the new downsized MotoGP formula featuring pneumatic valve operation.
In fact Kawasaki's ZX-RR 800 was the surprise package of the season, delivering a turn of speed that consistently put its Yamaha and Suzuki rivals in the shade-and Honda on occasion, too. Luckily I was given five laps on both Randy de Puniet's bike (who finished second at a rain-sodden Motegi GP) and also teammate Anthony West's machine. I found it hard to get comfortable on de Puniet's Kawasaki, not only because of the very aggressive pickup his bike had from a closed throttle but also the peculiar riding setup he opts for-with a thick carbon pad fixed to the back of the seat to force him as far forward as possible, presumably to load up the front wheel with his body weight. I was wedged firmly in place and it was impossible to move around. To make matters worse, the Frenchman had the front brake and clutch pointing skyward motocross-style, so to squeeze them I had to rotate my wrists. I ended up getting a cramp in my right wrist while trying to brake at the end of the back straight.
Fortunately the other side of the Kawasaki coin was shown to me via five laps aboard Ant West's bike. This was a completely different machine to ride, with an altered engine management program that made the initial throttle response less jerky and much more controllable-although for what turned out to be surprising reasons. "Anthony is an animal with the throttle," says West's crew chief, Fiorenzo Fanali, who started out in GP racing back in the '70s wrenching MV Agustas for Agostini and Read. After 30 years of working for the Japanese manufacturers there's not much Fanali doesn't know about GP racing. " uses it like a light switch-either full open or right off. Nothing in between." Kawasaki's electronics guru Andrea Dosoli has concocted a program for the Magneti Marelli Marvel 4 ECU to offset this brutal throttle usage by controlling the first 40 percent of throttle opening to deliver a smoother response no matter how quickly West twists it. Call it pre-traction control, basically softening initial throttle inputs while still delivering optimized acceleration once wide open. Electronics have an answer to everything today.
This extra control meant I could start to ride the Kawasaki harder, getting a taste of the free-revving pneumatic-valve engine's impressive performance. Having just stepped off Nicky Hayden's RC212V Honda I could make some direct comparisons, and it seemed the Kawasaki motor was stronger down low than the Repsol bike, pulling hard and clean from as low as 7800 rpm on the clearly readable 2D liquid-crystal display dash (much better than the Marelli LCD on the GP7 Ducati). But although its power delivery is very linear and the eager-revving engine builds power quickly, the Kawasaki's midrange felt weaker compared with the Honda-and not quite as powerful on top. The row of red shifter lights across the top of the dash all flash together at 17,800 rpm with the rev limiter cutting in at 18,300 rpm; you can feel the engine is still pulling, so presumably that's for durability reasons.
But the linear power delivery meant I could hold second gear all through the Valencia infield as West informed me he also does, despite the bottom four ratios on the Kawasaki transmission being quite tightly spaced, more so than the Honda's gearbox. At least the ZX-RR 800 Kawasaki isn't as much of a wheelie hound as its 990cc big brother was; this one just hovers the front wheel about six inches above the tarmac as you powershift through the race-pattern gearbox. The somewhat stretched-out 57.5-inch wheelbase-actually a little shorter than the 990 ZX-RR-surely helps here.
While the '07-model 990cc ZX-RR felt like the smallest and most agile bike on the grid, the 800cc Kawasaki feels bigger, especially when compared with the diminutive Honda. Although the chassis is new to accommodate the more compact pneumatic-valve motor, it's probably retained the same dimensions as the 990 frame, just with detail changes to the geometry and architecture. It still feels low-slung, though you do sit notably higher off the ground compared with the Ducati, especially on de Puniet's bike, which was higher at the rear than West's more balanced setup. The Frenchman obviously likes to ride the bike on the front wheel, which makes it turn in very well with loads of confidence in the front Bridgestone without seeming to affect stability or rear grip-not that I was able to push the Kawasaki's traction control the way he does.
The ZX-RR 800 offers nimble yet predictable handling, turning in nicely while trail-braking, and holds a tight line with good turn speed, though it's important to be on the gas to make it do so. Kawasaki has the engine braking really well dialed in via the mechanical slipper clutch and variable idle-speed program. There seems to be just enough when you need it to help the Brembo carbon brakes do their usual superlative job of hauling the Kawasaki down from speed without any chatter, as I downshifted two or three gears together in a hurry. You must use the clutch for downshifting on the Kawasaki, unlike some of the other MotoGP machines. There's no need to blip the throttle on downshifts, however; the electronics still take care of the rest.
The Kawasaki cockpit is less busy than some of its rivals. The gray button on the left clip-on is the pit-lane speed limiter, which requires you to hold it in until you're clear of the pits. The red button above it offers a choice of two different engine maps, with a softer one available for later in the race when tires are worn. These maps are comprehensive; they encompass traction control, fuel mapping, idle speed for engine braking, antiwheelie control and so on. There are no individual adjustments for any of these available, so you can't dial in a little bit more this or a little bit less that as on many other bikes. Just shut up and ride!
Which is what John Hopkins will surely do, but to a point-he'll have lots of feedback to give Fanali to bring the ZX-RR 800 forward with some serious R&D. The Kawasaki is very much a work in progress. It's a much better bike than the 990 ever was, although the 800 still feels a little unrefined compared with its rivals. But I get the feeling it has lots of potential, and I reckon Hopper is the man to turn it into a contender, with a more settled Westy as his backup. Kawasaki will be the one to watch in 2008. It has the basis of a good bike here, one that just needs to be whipped into shape.
KAWASAKI ZX-RR 800 TECH - Yoda Speaks
When former Yamaha MotoGP project leader Ichiro Yoda joined Kawasaki's MotoGP project for the '05 season he brought with him more than 20 years of Grand Prix engineering experience-never mind dramatically overturning the convention that senior Japanese executives never switch from one manufacturer to another. Yoda is a hardened racing enthusiast and has been the driving force behind the development of Kawasaki's 990cc ZX-RR Ninja. But for the '07 Grand Prix season Yoda took on a new role as race director with the reorganized Kawasaki Racing Team.
Alan Cathcart: What were your priorities for developing Kawasaki's new ZX-RR 800?</strong>
Ichiro Yoda: We knew from the start that we would have to rev the 800cc engine harder and higher than before to find enough power to be competitive. We calculated we would need to rev the first evolution of the new engine to 18,000 rpm to achieve our power target, and at this level a conventional valvetrain with closing springs is inefficient. So our first major decision was to run a pneumatic valve system on the new engine. This technology is not widely used in the motorcycle industry, so we had to bring this technology in from an outside supplier. But as a lot of people have discovered to their cost in the past, the technology doesn't transfer directly. A lot of modifications are required to take what is effectively Formula 1 racing car technology and apply it to the very unique characteristics of a racing motorcycle.
Of course we didn't just design the cylinder head first and then think about the rest of the bike afterward. We decided to use a pneumatic cylinder head because of the increased revs, but that had a spin-off effect on the rest of the bike. The pneumatic head is lighter than a conventional cylinder head, and it's also physically smaller. This means the engine is more compact, but it also moves the center of gravity compared to an engine that utilizes a conventional head. So we could achieve improved mass centralization. By centralizing the mass and then positioning that mass in the right place in the chassis, you produce a bike that is more agile and easier for the rider to turn, especially at high speed. Quick and accurate turning is critical to a good lap time, especially with the new 800cc machines. The other advantage of mass centralization is stability under braking, and this is also important in terms of lap time.
AC: Was the unorthodox rear shock mount on the new 800cc Kawasaki also designed to improve mass centralization?
IY: For sure. One of the reasons we run an unorthodox mount for the rear shock by effectively running it upside down in the chassis is that it places the majority of the weight closer to the central mass of the engine. But the main reason for using this method of mounting the rear shock was for ease of maintenance. Running the inverted shock makes changing the spring and altering suspension settings much easier and much quicker to do when the pressure is on during practice and qualifying.
AC: How many parts does the new 800cc ZX-RR have in common with the old 990?
IY: The 800cc machine is an evolution of the 990cc bike, so we have taken what we learned during the past four years and incorporated those lessons into the design of the new machine. Yes, there are some parts that remain from the 990, such as the running gear and bodywork, but the major components like the engine and chassis are all new, although the bore-to-stroke ratio of the engine did not change so much. This is a motorcycle, not a car, so we do not use an extreme short stroke. The chassis is very similar to the final 990 version, although we changed dimensions slightly, and also the center of gravity is altered.
But we made many experiments with different stiffness of the chassis and swingarm, especially in relation to each other. The 990cc bikes had so much power that a lot of our development time was spent trying to counter the tendency to lose grip at the rear under acceleration. The bigger bike could feel quite nervous to the rider on the throttle, and when it did lose rear traction it did so suddenly. The characteristics of the 800cc ZX-RR are that it's easier to control on the throttle, and the transition between grip and no grip is both smoother and more predictable. The engine is the input for the whole system. Because the engine is smoother with the 800cc bike it means the whole system is more stable, so now we can experiment with chassis and swingarm stiffness to get ideal handling characteristics.
AC: Valentino Rossi is reported as saying that you need a V-four engine to win in MotoGP. So is Kawasaki working on such an engine for the future?
IY: This is stupid! Each kind of configuration has its own advantages, and Ducati is not winning just because it is a V-four! Kawasaki has very much experience of inline-four-cylinder engineering, and we will continue in this direction, not produce our own Ducati copy. We believe the handling advantage of our inline engine comes from a more compact mass and this makes a better package compared to a V-four-also because a V-four is more difficult to fit in a chassis, and maintenance is more complicated, too. Maybe for Honda this is OK, because they have a lot of V-four experience. But for Kawasaki this is not the case, so we will continue to follow our experience with the inline layout.
Photo Gallery: Kawasaki ZX-RR 800 - Less Mean Greenie - Sport Rider Magazine (http://www.sportrider.com/features/146_0805_kawasaki_zx_rr_800)
http://images.sportrider.com/features/146_0805_01_s+kawasaki_ZX-RR_800+three_quarter_view.jpghttp://images.sportrider.com/features/146_0805_02_s+kawasaki_ZX-RR_800+left_lean.jpg
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http://images.sportrider.com/features/146_0805_01_z+kawasaki_ZX-RR_800+three_quarter_view.jpgIt was all change for Kawasaki's MotoGP effort in 2007, with the previously European-run race team put under the direct factory control of experienced Grand Prix stalwart Ichiro Yoda. The team's European base moved to Holland from Germany, and an all-new motorcycle, the ZX-RR 800, was created for the new downsized MotoGP formula featuring pneumatic valve operation.
In fact Kawasaki's ZX-RR 800 was the surprise package of the season, delivering a turn of speed that consistently put its Yamaha and Suzuki rivals in the shade-and Honda on occasion, too. Luckily I was given five laps on both Randy de Puniet's bike (who finished second at a rain-sodden Motegi GP) and also teammate Anthony West's machine. I found it hard to get comfortable on de Puniet's Kawasaki, not only because of the very aggressive pickup his bike had from a closed throttle but also the peculiar riding setup he opts for-with a thick carbon pad fixed to the back of the seat to force him as far forward as possible, presumably to load up the front wheel with his body weight. I was wedged firmly in place and it was impossible to move around. To make matters worse, the Frenchman had the front brake and clutch pointing skyward motocross-style, so to squeeze them I had to rotate my wrists. I ended up getting a cramp in my right wrist while trying to brake at the end of the back straight.
Fortunately the other side of the Kawasaki coin was shown to me via five laps aboard Ant West's bike. This was a completely different machine to ride, with an altered engine management program that made the initial throttle response less jerky and much more controllable-although for what turned out to be surprising reasons. "Anthony is an animal with the throttle," says West's crew chief, Fiorenzo Fanali, who started out in GP racing back in the '70s wrenching MV Agustas for Agostini and Read. After 30 years of working for the Japanese manufacturers there's not much Fanali doesn't know about GP racing. " uses it like a light switch-either full open or right off. Nothing in between." Kawasaki's electronics guru Andrea Dosoli has concocted a program for the Magneti Marelli Marvel 4 ECU to offset this brutal throttle usage by controlling the first 40 percent of throttle opening to deliver a smoother response no matter how quickly West twists it. Call it pre-traction control, basically softening initial throttle inputs while still delivering optimized acceleration once wide open. Electronics have an answer to everything today.
This extra control meant I could start to ride the Kawasaki harder, getting a taste of the free-revving pneumatic-valve engine's impressive performance. Having just stepped off Nicky Hayden's RC212V Honda I could make some direct comparisons, and it seemed the Kawasaki motor was stronger down low than the Repsol bike, pulling hard and clean from as low as 7800 rpm on the clearly readable 2D liquid-crystal display dash (much better than the Marelli LCD on the GP7 Ducati). But although its power delivery is very linear and the eager-revving engine builds power quickly, the Kawasaki's midrange felt weaker compared with the Honda-and not quite as powerful on top. The row of red shifter lights across the top of the dash all flash together at 17,800 rpm with the rev limiter cutting in at 18,300 rpm; you can feel the engine is still pulling, so presumably that's for durability reasons.
But the linear power delivery meant I could hold second gear all through the Valencia infield as West informed me he also does, despite the bottom four ratios on the Kawasaki transmission being quite tightly spaced, more so than the Honda's gearbox. At least the ZX-RR 800 Kawasaki isn't as much of a wheelie hound as its 990cc big brother was; this one just hovers the front wheel about six inches above the tarmac as you powershift through the race-pattern gearbox. The somewhat stretched-out 57.5-inch wheelbase-actually a little shorter than the 990 ZX-RR-surely helps here.
While the '07-model 990cc ZX-RR felt like the smallest and most agile bike on the grid, the 800cc Kawasaki feels bigger, especially when compared with the diminutive Honda. Although the chassis is new to accommodate the more compact pneumatic-valve motor, it's probably retained the same dimensions as the 990 frame, just with detail changes to the geometry and architecture. It still feels low-slung, though you do sit notably higher off the ground compared with the Ducati, especially on de Puniet's bike, which was higher at the rear than West's more balanced setup. The Frenchman obviously likes to ride the bike on the front wheel, which makes it turn in very well with loads of confidence in the front Bridgestone without seeming to affect stability or rear grip-not that I was able to push the Kawasaki's traction control the way he does.
The ZX-RR 800 offers nimble yet predictable handling, turning in nicely while trail-braking, and holds a tight line with good turn speed, though it's important to be on the gas to make it do so. Kawasaki has the engine braking really well dialed in via the mechanical slipper clutch and variable idle-speed program. There seems to be just enough when you need it to help the Brembo carbon brakes do their usual superlative job of hauling the Kawasaki down from speed without any chatter, as I downshifted two or three gears together in a hurry. You must use the clutch for downshifting on the Kawasaki, unlike some of the other MotoGP machines. There's no need to blip the throttle on downshifts, however; the electronics still take care of the rest.
The Kawasaki cockpit is less busy than some of its rivals. The gray button on the left clip-on is the pit-lane speed limiter, which requires you to hold it in until you're clear of the pits. The red button above it offers a choice of two different engine maps, with a softer one available for later in the race when tires are worn. These maps are comprehensive; they encompass traction control, fuel mapping, idle speed for engine braking, antiwheelie control and so on. There are no individual adjustments for any of these available, so you can't dial in a little bit more this or a little bit less that as on many other bikes. Just shut up and ride!
Which is what John Hopkins will surely do, but to a point-he'll have lots of feedback to give Fanali to bring the ZX-RR 800 forward with some serious R&D. The Kawasaki is very much a work in progress. It's a much better bike than the 990 ever was, although the 800 still feels a little unrefined compared with its rivals. But I get the feeling it has lots of potential, and I reckon Hopper is the man to turn it into a contender, with a more settled Westy as his backup. Kawasaki will be the one to watch in 2008. It has the basis of a good bike here, one that just needs to be whipped into shape.
KAWASAKI ZX-RR 800 TECH - Yoda Speaks
When former Yamaha MotoGP project leader Ichiro Yoda joined Kawasaki's MotoGP project for the '05 season he brought with him more than 20 years of Grand Prix engineering experience-never mind dramatically overturning the convention that senior Japanese executives never switch from one manufacturer to another. Yoda is a hardened racing enthusiast and has been the driving force behind the development of Kawasaki's 990cc ZX-RR Ninja. But for the '07 Grand Prix season Yoda took on a new role as race director with the reorganized Kawasaki Racing Team.
Alan Cathcart: What were your priorities for developing Kawasaki's new ZX-RR 800?</strong>
Ichiro Yoda: We knew from the start that we would have to rev the 800cc engine harder and higher than before to find enough power to be competitive. We calculated we would need to rev the first evolution of the new engine to 18,000 rpm to achieve our power target, and at this level a conventional valvetrain with closing springs is inefficient. So our first major decision was to run a pneumatic valve system on the new engine. This technology is not widely used in the motorcycle industry, so we had to bring this technology in from an outside supplier. But as a lot of people have discovered to their cost in the past, the technology doesn't transfer directly. A lot of modifications are required to take what is effectively Formula 1 racing car technology and apply it to the very unique characteristics of a racing motorcycle.
Of course we didn't just design the cylinder head first and then think about the rest of the bike afterward. We decided to use a pneumatic cylinder head because of the increased revs, but that had a spin-off effect on the rest of the bike. The pneumatic head is lighter than a conventional cylinder head, and it's also physically smaller. This means the engine is more compact, but it also moves the center of gravity compared to an engine that utilizes a conventional head. So we could achieve improved mass centralization. By centralizing the mass and then positioning that mass in the right place in the chassis, you produce a bike that is more agile and easier for the rider to turn, especially at high speed. Quick and accurate turning is critical to a good lap time, especially with the new 800cc machines. The other advantage of mass centralization is stability under braking, and this is also important in terms of lap time.
AC: Was the unorthodox rear shock mount on the new 800cc Kawasaki also designed to improve mass centralization?
IY: For sure. One of the reasons we run an unorthodox mount for the rear shock by effectively running it upside down in the chassis is that it places the majority of the weight closer to the central mass of the engine. But the main reason for using this method of mounting the rear shock was for ease of maintenance. Running the inverted shock makes changing the spring and altering suspension settings much easier and much quicker to do when the pressure is on during practice and qualifying.
AC: How many parts does the new 800cc ZX-RR have in common with the old 990?
IY: The 800cc machine is an evolution of the 990cc bike, so we have taken what we learned during the past four years and incorporated those lessons into the design of the new machine. Yes, there are some parts that remain from the 990, such as the running gear and bodywork, but the major components like the engine and chassis are all new, although the bore-to-stroke ratio of the engine did not change so much. This is a motorcycle, not a car, so we do not use an extreme short stroke. The chassis is very similar to the final 990 version, although we changed dimensions slightly, and also the center of gravity is altered.
But we made many experiments with different stiffness of the chassis and swingarm, especially in relation to each other. The 990cc bikes had so much power that a lot of our development time was spent trying to counter the tendency to lose grip at the rear under acceleration. The bigger bike could feel quite nervous to the rider on the throttle, and when it did lose rear traction it did so suddenly. The characteristics of the 800cc ZX-RR are that it's easier to control on the throttle, and the transition between grip and no grip is both smoother and more predictable. The engine is the input for the whole system. Because the engine is smoother with the 800cc bike it means the whole system is more stable, so now we can experiment with chassis and swingarm stiffness to get ideal handling characteristics.
AC: Valentino Rossi is reported as saying that you need a V-four engine to win in MotoGP. So is Kawasaki working on such an engine for the future?
IY: This is stupid! Each kind of configuration has its own advantages, and Ducati is not winning just because it is a V-four! Kawasaki has very much experience of inline-four-cylinder engineering, and we will continue in this direction, not produce our own Ducati copy. We believe the handling advantage of our inline engine comes from a more compact mass and this makes a better package compared to a V-four-also because a V-four is more difficult to fit in a chassis, and maintenance is more complicated, too. Maybe for Honda this is OK, because they have a lot of V-four experience. But for Kawasaki this is not the case, so we will continue to follow our experience with the inline layout.
Photo Gallery: Kawasaki ZX-RR 800 - Less Mean Greenie - Sport Rider Magazine (http://www.sportrider.com/features/146_0805_kawasaki_zx_rr_800)
http://images.sportrider.com/features/146_0805_01_s+kawasaki_ZX-RR_800+three_quarter_view.jpghttp://images.sportrider.com/features/146_0805_02_s+kawasaki_ZX-RR_800+left_lean.jpg
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