Motorcycle News
07-01-2008, 06:09 AM
Ducati Desmosedici GP7, Yamaha YZR-M1, Honda RC212V - MotoGP Rides - Special Section
http://images.sportrider.com/features/146_0804_01_z+motoGP_rides+ducati_desmosedici_GP7. jpgDucati Desmosedici GP7
Casey's Cannonball
Let's face it: We all like it when the little guy wins. When the underdog upsets the odds. When ingenuity, passion and determination all pay off-including the foresight to gamble on building a bike like the Ducati Desmosedici GP7.
The chance to ride Casey Stoner's bike at the annual promofest press test after the Valencia GP promised to give at least the hint of an answer as to how the modern-day David triumphed over Goliath. Only one thing was wrong-well, two, actually. A crowd of people slated to ride the Ducati meant each person was limited to only four laps on the GP7. And to top it all off? "We know the track conditions aren't so good first thing in the morning after the overnight cold, so we need an experienced pair of hands to start the test," said Ducati PR exec Federica de Zottis. "You're up first!"
Well, of course I did as I was asked, rather than spit the dummy-wouldn't you? But this glimpse of the promised land was doubly frustrating because the Ducati is so different from all the other bikes. For a start it has quite different architecture from its Japanese rivals, being longer, lower and more voluptuous to look at. The seat is much lower than on the others, but it has a very distinctive riding position with extremely high footrests plus a wide and flat angle to the clip-on handlebars, where I'd expected steeply dropped clip-ons befitting someone from the 125/250GP classes like Stoner. "Don't forget, I'm a dirt-track graduate. That's where I learned how to race back home in Oz as a kid," Stoner explained about his bar angle.
After climbing aboard and settling into the hot seat I found the ergos to be surprisingly spacious, except for those high footpegs. They made the race-pattern gearbox quite hard to backshift on because of the raised lever that's also lifted to stop it from grounding at full lean. (According to telemetry graphs Stoner frequently leans over as far as 60 degrees from vertical.) Firing up the GP7 on the rollers produced a glorious sound from the twin 2-into-1 exhausts. The "screamer"-firing-order engine used this year has allowed Ducati to revert to these, in contrast to the four separate megaphones required by the old "Twin Pulse" 990. The lumpy, offbeat, 3000-rpm idle speed is deliberately set high to help offset engine braking when you close the ride-by-wire throttle entering a turn.
The fact that you can't easily read the tachometer isn't important, because the Ducati's broad spread of power makes it almost unnecessary. I expected the GP7's delivery to be quite peaky and the powerband relatively narrow, in pursuit of that all-conquering performance-but if anything it was quite the opposite. Though it doesn't pull quite as strongly from down low as the Suzuki and Kawasaki, the Ducati accelerates very hard from around 11,000 rpm onwards. There's a meaty spread of midrange power as it builds furiously toward the 19,000-rpm rev limiter dialed in for this press test (20,000-plus rpm in race guise has been rumored). A row of blue lights starts flashing at 18,500 rpm to tell you now might be a good time to upshift, as the Ducati accelerates like a missile while the Marelli anti-wheelie program stops the front wheel from lifting more than a few inches off the ground.
What about the traction control? Well, that only works when you're riding the bike the way it should be ridden. In just four early morning laps I'll admit that in right-handers I wasn't prepared to give it the berries because of concern about tread temps on that side of the tire. Valencia's numerous left-handers were another matter, and there I could revel in the Desmosedici 800's fantastic drive as the Marvel 4 ECU's electronics played a silent part in hooking up the rear tire. Just as when I rode Troy Bayliss' factory V-twin Superbike back in the summer of 2007, there's no sense that ignition advance is being held back or fueling leaned off, or that some unseen hand is winding back the GP7's throttle without your knowing it. There's no machine-gun stutter like Ducati's Superbikes once made, either-just a sense of unseen control that brings confidence in its wake.
But perhaps the biggest surprise in riding the Ducati GP7 is how smooth the response is when you get back on the gas again to drive out of a turn after using the monster power of the Brembo carbon brakes and the effective ramp-style slipper clutch to run deep into the turns. The electronics do their bit in softening the initial response-but only that. While there's none of the fierce power delivery from a closed throttle that the exhaust's raw-edged roar would lead you to expect, that doesn't mean that acceleration is anything less than awesome when you get the GP7 straightened up and fired out of the exit of the turn. Instead, once again the Ducati is simply well controlled. Ducati Corse engineers have cleverly mapped all the electronics to make the GP7 incredibly user-friendly for such a powerful motorcycle. There are myriad adjustments possible, but with just four laps I wasn't about to start playing around with the range of different settings for traction control and engine maps accessible by punching buttons in the busy-looking cockpit.
It's hard to ignore the Desmosedici motor, but as Stoner repeatedly proved it's the overall package that delivers the goods. The Ducati seemed to change direction better than all but the Honda, especially in the two Valencia chicanes where it flicked from side to side much more eagerly than its 990cc GP6 predecessor. And where that bike pushed the front wheel rounding the long left up over the hill leading into the last turn, the 800cc GP7 held a tight line much better. It needs to be kept hard on the gas to do this, but there's no doubt this is a better-steering bike than its predecessor.
I thought before I rode it that the Desmosedici GP7 would be all motor, or that maybe, as a certain Italian rider insists, the Ducati only won the world title because of Bridgestone's superiority or the GP7's high degree of electronic control that makes the pilot less important, F1-style. But it's easy to see it was all that plus Stoner's skill in riding the GP7 exactly as it needed to be ridden, as well as his newfound consistency in finishing every race, thanks mainly to a front tire he could trust. The Ducati GP7 is a bike that is beyond criticism from anyone except its regular rider. Only on tight, twisty tracks like Sachsenring and Valencia was it anything other than totally dominant; and judging by Stoner's times in Valencia testing the day after my ride, the GP8 that's been on track since March may very well have addressed that. Will 2008 be the start of a Ducati dynasty in MotoGP under the 800cc formula, like the Italian marque enjoyed in World Superbike for so long?
Ducati Desmosedici Gp7-How And Why
The man primarily responsible for creating the MotoGP title-winning Ducati GP7 is 39-year-old Filippo Preziosi, the direttore generale of Ducati Corse since 2005. Preziosi was the racing subsidiary's technical director starting in 2000, heading up engine and electronics R&D for both Superbike and MotoGP race projects. When Ducati announced it was entering MotoGP with a V-four-powered prototype, the big engineering decisions regarding the Desmosedici's layout and detail during development fell upon his shoulders.
"We at Ducati were very opposed to the change of rules from 990cc to 800cc for MotoGP, because that means you have to throw away your old engine and build a completely new bike, which costs a lot of money," Preziosi recalls. "Our company is a small one, our resources are limited, so for us it would have been much better to keep what was already working well. We needed to understand what in the GP6 was working correctly and try not to change any of that. So we concentrated only on what was absolutely necessary to change in going to 800cc.
"We decided to keep several parts. For example, we kept the front end of the bike: the front fork, the rims, brake calipers and so on. And we did the same thing with the rear; we kept the swingarm, the link, the shock absorber, the brakes, wheels, we kept everything more or less exactly the same. We also kept the same clutch from 2006; it was working properly, so we didn't find any reason to change it, and the same was true for the gearbox. The torque of the engine is greater on the 990 than the 800, but there are some differences in the firing order, so that made us think we should keep the same transmission. Just because you have a smaller-capacity 800cc engine, you might think that because the power and torque will therefore be less, you can make a smaller, lighter gearbox. But in reality, the power you are using is limited by the vehicle dynamics, not by the engine. So even if you have a 990 with more power and more torque, at the end of the day the power you are using when you are exiting the corner in third gear is the power allowed by the dynamics: wheelies, tire grip and so on.
"The marketing people at Ducati were not at all happy with the way we designed the GP7," Preziosi reveals, "because we kept more or less the same bodywork as the GP6, and that means it's more or less the same fairing as the GP3! Because people were expecting a big difference from 990 to 800, a lot of journalists were upset that we designed the GP7 bodywork to be so similar to the GP6. But the main point for a racing bike is to be fast, not to be different, so we tried to concentrate our efforts to have a faster bike, not a different bike."
Obviously the engine is where the majority of development was concentrated. "So we started to think what was the best configuration, with how many cylinders and how they should be arranged," says Preziosi. "We absolutely did not commit to simply downsizing the existing Desmosedici motor-all options were open. We did many simulations, but at the end of the day the answer was the same. We think that the 90-degree V-four is the best configuration, not only for engine performance, but also the entire layout of the bike. The mass is very concentrated, the internal balance of the engine is very good, the weight distribution of the motorcycle is what we are searching for, and the fuel consumption is under control, and the engine is very efficient."
Petroleum giant Shell also played a significant role in the Desmosedici's design. "In creating the new engine, we worked very closely with our partners at Shell. We relied on them to help deliver the efficiency that was so important for the kind of bike that we were planning to build, and that meant working on the fuel and oil side as well as the mechanical design. The first key ingredient of this was to reach high revs in order to achieve high power figures. With the 990 the power was not so important, because the performance was more defined by the vehicle dynamics; if the front wheel isn't touching the ground, there's no reason to have more power. But moving from 990 to 800, it seemed that output would be less, so the amount of power compared to our rivals would be more important, in which case the easiest way to reach more power is to increase revs. But unfortunately there are a lot of problems in doing that, and the first one is that fuel efficiency becomes an issue, so you have to make some decisions to avoid fuel consumption getting too high, especially with the smaller 21-liter fuel tank introduced for this season. We worked a lot on engine fluid dynamics to resolve this problem.
"The second key decision was to keep the screamer firing order," Preziosi continues. "This was completely the opposite compared to the rest of the MotoGP paddock, where technicians, riders, mechanics, journalists, everyone all insisted the screamer engine was too aggressive, that rideability was the most important thing in the world. We're fighting with Valentino Rossi, who is seven times world champion, we're fighting against Honda, who are 14 times world champion, we're fighting against Michelin, who are 26 times world champion. So if we choose to follow the same way as them, there is no chance to win. Ducati has to change something; we have to do things differently. So we felt this was the right choice. We thought that with the high revs and the screamer firing order, we could get more power, and that fuel consumption wasn't going to be an issue because the engine was more efficient. Of course, if Casey was not the Casey we know and admire so much, maybe we would have had a very bad season, and now I would have had to apologize for making the wrong choice! But thanks to Casey we're laughing and I can tell you how intelligent we were!"
During chassis development with the GP7, Ducati engineers made a surprising discovery. "On the chassis side, we believed our 990 GP6 had some problems, and we worked a lot on the frame to try to understand where these came from," Preziosi explains. "Loris complained the bike was not so stiff; he said there was some delay in its response. So we studied this a lot and eventually realized the problem was not on the chassis itself but on the stiffness of the footrest hangers! As you know, when you ride a bike you steer it not only with the handlebars, but also by shifting your body weight on the footrests. So in creating the GP7 we extended the concept we introduced in 2003, making the engine the central part of the motorcycle. Usually in every MotoGP bike the engine is a stressed component of the rolling chassis, so without the engine the wheel-to-wheel stiffness is less. But on the GP7 the engine is a part of the frame, so it's not possible to place the two wheels on the ground without it. This allows us to have a different structure with less weight, and the rear section of the frame is now a lot different to the GP3-GP6, with a carbon-fiber subframe that makes a really stiff structure, and the footrest hangers are now well supported."
Preziosi then reveals how much a role electronic rider aids now play in MotoGP. "We did a lot of work during the 2007 season on the electronics management and continued improving the electronics race by race, just as we did in 2006. The hardware is basically the same; we just changed the software strategy we wanted to apply for the 800 against the 990. The main point of the electronics was to improve rideability, because the specification we decided on for the engine was very good in delivering power, very good in fuel efficiency, but maybe not so good in rideability. This meant we just did different things with the same hardware for the GP7, because this is something very easy and cheap to do. If you have a good idea lying in bed at night, and you put the idea on the software in the morning, look at it in the system and you find that it's working well, you just have to use the ADSL connection to send it to Sepang or Le Mans or wherever the team is, and they can test it and find they have a different bike. With this kind of electronic management we can practically make a different bike with the same hardware for every track, for every rider, for every corner, in every weather condition. We can have a lot of different bikes in the same bike!"
Fiat Yamaha YZR-M1 800
Racing Relativity
The chance to ride Valentino Rossi's Yamaha YZR-M1 at Valencia after a season that saw him finish outside the top two championship places for the first time since his debut year in 125 Grand Prix back in 1996 was even more of an honor than usual, as I was one of just five journalists invited to do so. Ten laps on the bike not only made it a proper test rather than a showbiz stunt, it also allowed me to learn a lesson in two-wheeled relativity. Although everyone (including myself) who rode the Yamaha and Ducati proclaimed the YZR-M1 to be much easier to ride and a more complete package, the results column and Rossi's constant complaints regarding the Yamaha's lack of speed obviously showed how different things are when ridden at title-contending pace.
The two bikes could hardly be more different to sit on. While the Ducati is low-slung and stretched out, the more compact Yamaha has a much taller ride height. Asking Rossi's legendary race engineer Jerry Burgess why it was set up that way yields an interesting explanation. "It's because a couple of hours into the project, when Valentino was riding the Yamaha for the first time four years ago, we replaced the small 290mm discs they were using back then with bigger 320mm ones to get it to stop," Jerry recalls. "But then he complained he was locking the front brake, so it was obvious the low center of gravity the Yamaha had back then didn't work in delivering sufficient weight transfer under braking to load up the front wheel so the tire could grip. One way to deal with that is to lift the engine in the frame, or else you can just run the bike higher at both ends, which is what we did then as a quick fix and have done ever since."
The uncluttered cockpit has a white toggle switch on the left clip-on allowing you to scroll through the three different engine maps carried within the Magneti Marelli ECU, with a yellow launch control button above that for starts and the front brake lever adjuster knob just behind. These are matched on the right handlebar by the red kill-switch button, surmounted by a green one to press for the pit lane speed limiter, while the dash has last lap and best lap times prominently shown, plus an abbreviated analog tachometer display. But these are quite small because Rossi and teammate Colin Edwards II shift entirely by sound and feel, as well as the half-dozen small shifter lights which start flashing in unison at 18,300 rpm, followed by the bright-red shift light above them 500 rpm later before the harsh 19,000 rpm rev limiter. There's also a large gear indicator in the top right-hand corner of the dash, which is really welcome.
The YZR-M1's gruff-sounding but easy-revving 800cc 16-valve DOHC engine is surprisingly flexible and forgiving, pulling strongly from as low as 9000 rpm, then building power fast and strong once past the five-figure mark. It's not as peaky as you might expect given the smaller engine displacement, and the delivery is pretty linear and tractable. However, the Yamaha has more of a wheelie tendency than even its 990 predecessor did, which is another surprise, especially given that its ride-by-wire throttle control program is much less abrupt than all its rivals-save for the Ducati, with which the Yamaha shares the same Marelli Marvel 4 ECU. Besides continually pointing the front end skyward in each of the first three gears the Yamaha would even pull a long, lazy fourth gear power-wheelie down the front straight, lofting the front wheel controllably six inches above the tarmac, seemingly without sacrificing much acceleration. Much of this happens if you don't wait for the small lights on the top of the dash to all flash together from 18,300 rpm upward, because you then end up grabbing a higher ratio before the torque curve peaks.
Despite the wheelie tendency, the Yamaha is really well rounded and user-friendly to ride, especially the smooth yet strong throttle response when you get back on the gas again exiting a turn. Unlike the more powerful 990 with its comparatively brutal power delivery, on the 800 you can get on the throttle harder while still leaned over, accelerating on the edge of the tire to maintain momentum. With the Yamaha's smooth but effective throttle response, you can keep up corner speed knowing that when you get hard on the gas again you're not going to spin the back wheel because of the 990's big hit of power.
While I thought the 990cc YZR-M1 was hard work a year ago to make major steering changes, the agility of the 800cc version in the turns is outstanding. It's even more nimble than the more minuscule Honda, but without sacrificing anything in stability when you squeeze hard on the slightly dead-feeling four-pad/four-piston Brembo carbon brakes in a desperate attempt to slow the bike down from high speed. The Yamaha stayed glued to the line I had chosen, and as with the 990 YZR-M1, you can feel there's just enough engine braking delivered by the combination of the mechanical slipper clutch and ICS variable-idle system as you back down through the gears in quick succession (while always using the clutch to do so, however, just as Valentino does).
Once again, as in the past, you have the feeling this bike was carefully improved and demandingly refined by an expert in the art of setup, resulting in a package so capable it's almost beyond criticism. But only, it seems, at press-tester speed, although let's not forget this bike won four GP races this past season. "It's a good package, for sure," Burgess says. "I believe we've got a very, very good-handling motorcycle. But what we need is a little more push from the engine, a little more grip from the tires and a lot better reliability from the motorcycle as a whole. You can't afford a single DNF these days; look at how Stoner scored points in every race this year, which is a great achievement by Ducati as well as Casey himself, and we've got to match that next season. When you get a valve-spring engine turning at 19,000 rpm, the valve lift you can use is compromised, and even though the spring component may be all right you need very special spring wire-and the mass of everything is critical. It also compromises your choice of camshaft design and engine characteristics, so for sure pneumatics is the way to go. But for 2008 our primary focus is to take the bike as it is but with a better, more dependable motor and stick Bridgestones on it without sacrificing any of the many good things it has about it already. If we can do that, it's up to Valentino to do the rest-and we all know that he can!"
Fiat Yamaha YZR-M1 800 Tech
Yamaha's R&D team, headed by YZR-M1 project leader Kouichi Tsuji, developed a contender for the new 800cc category that was substantially based on the previous 990cc bike, aiming to retain the advantages of its inline-four-cylinder format and especially the proven chassis design. Rossi struggled for much of 2006 with midcorner chatter problems that were only resolved with the introduction of a new Deltabox frame design with altered rigidity specs for the final five races of the 990cc era. "After we found a chassis that performed satisfactorily, we were reluctant to discard it for the new formula," says Yamaha race boss Masao Furusawa. "So we retained the same essential format and developed an engine which took many lessons from our final-version 990cc power unit."
The DOHC 16-valve, inline-four-cylinder engine's overall dimensions are naturally reduced compared with the 990, but the overall bore-and-stroke ratio is less oversquare than the bigger motor's ultrashort-stroke layout, according to Tsuji, to regain some of the torque sacrificed by the smaller displacement. The new engine is 3.5kg lighter and physically smaller than the 990, measuring 8mm narrower overall and 18mm shorter from the top of the cylinder head to the crankshaft, which is also 5mm closer to the swingarm pivot cast into the crankcases. The Nikasil cylinders carry two-ring aluminum pistons machined from solid metal, mounted on titanium conrods. As before, the aluminum crankcases are likewise machined from solid billet. The complexity of the CNC programming necessary to carve all these components from solid lumps of metal is obviously significant.
Yamaha retained the so-called "long bang" format of the 990cc bike on the 800cc motor, with the firing pulses on two cylinders closed up to around 60 degrees of crankshaft rotation, followed by a space of around 300 degrees before the next pair fire close together, intended to enhance traction and tire life. Like the 990, the YZR-M1 800 motor's crankshaft rotates backward, with an intermediate shaft located between the crankshaft and dry clutch. This is also fitted with weights to act as a counterbalancer, thus eliminating undue vibration resulting from the uneven firing order. The Termignoni titanium exhaust is now the only one on the MotoGP grid to be fitted with a silencer, because Rossi claims a loud exhaust robs him of concentration. Yamaha can afford the weight penalty this entails; the YZR-M1 800 weighs 328 pounds with oil and water (no fuel) just like its big brother did, 1kg more than the MotoGP weight limit-and for the same reason. "We need to be sure it is this way at the start of a race, since by the end when weight is checked, we will lose up to 0.8kg from tire wear and oil consumption," Tsuji says.
Yamaha used conventional valve springs in the engine for most of the '07 season with the belief that engine revs for the new-generation 800cc bikes would be limited by fuel consumption. "We believed that the new 21-liter fuel tank regulation would mean that engine speeds could not exceed 18,000 rpm without running out of fuel in a race," Furusawa admits, "and at these rpm it is still OK to use valve springs instead of a more complex alternative technology." This explains why Yamaha got smoked in the first race of the season at Qatar, when computer projections for fuel consumption caused them to back off engine speeds to 17,500 rpm, resulting in Stoner's D16 GP7 being timed at 202 mph down the Losail pit straight, against just 192.6 mph for Rossi's Yamaha. When it was discovered afterward that Rossi's bike still had more than a liter remaining in the fuel tank-against just a third of a liter for Stoner-Yamaha realized its mistake and raised revs to 18,000 rpm for the next race in Jerez, which Rossi duly won.
But even more revs weren't sufficient to keep up with the flying Italian bike that ran 209.4 mph versus the YZR-M1's 202.5 mph at Shanghai, where the Honda and Kawasaki were both faster, too. This forced Yamaha to accelerate development of a pneumatic-valve version of the motor, which debuted in postrace testing at Brno in August and was judged sufficiently promising for Rossi to race it two weeks later in Misano, only to DNF with a blown engine.
When a repeat failure occurred in testing in Japan, the decision was taken to park it on the sidelines for the time being, especially as Yamaha had by now developed a fourth version of the existing valve-spring motor, whose revs had been raised to 19,000 rpm without affecting fuel consumption and seemingly without any ill effects in terms of reliability. This proved a wise decision when Rossi won in Portugal using that uprated motor, delivering four percent more horsepower than at the start of the season.
The full ride-by-wire electronic throttle Yamaha introduced on the 990 last year is retained, but the lighter and more compact Magneti Marelli Marvel 4 ECU used this year delivers enhanced engine management that now includes the ability to alter engine mapping for every corner, as well as for each gear ratio selected. Tsuji confirms the ECU now recognizes each individual turn on the track, via an onboard GPS receiver. And most importantly, the Marelli ECU is now programmed to make extremely precise calculations for fueling the motor, which are thought to include the facility to automatically lean the engine out in any given corner to save fuel, before richening it up again for speed down the straight, as Ducati is known to do via the same ECU.
Comparative telemetry from Jerez of relative performance between the 990 and 800cc Yamahas showed that on the smaller bike, Rossi brakes 30 meters later and opens the throttle 15 meters earlier than on its more powerful predecessor, using about 10 percent more throttle overall than on the 990. And while this had a 3-5 percent faster top speed-about 6 mph quicker down a long front straight like the one at Mugello-the 800 is anywhere from 2-6 mph faster in turns. This underlined the critical ingredient of chassis design in creating the new bike. "The YZR-M1 frame is designed to keep the vertical stiffness and reduce lateral stiffness and torsion," Tsuji explains. "This is because when the bike is banked, the frame must also act as suspension. That is why we focus very much on this element with many tools and simulations, and why in 2005 we removed the cross-member of the frame. This reduced lateral and torsion stiffness and gave much improvement for agility and stability."
After thick 47mm Ohlins forks were also debuted at Mugello in an effort to give Rossi better feel during braking, overheating problems resulted from the big forks cutting off cooling airflow to the radiator. A new fairing was introduced at Brno to fix this, and that's what was on the bike at Valencia. The long swingarm delivers not only enhanced stability and traction in what is understood to be a relatively short wheelbase by current MotoGP standards, but also helps improve grip from the front 16-inch Michelin adopted this season, mated to a 16.5-inch rear. The reason for using a 220mm ventilated steel disc at the rear, in contrast to the big 320mm carbon discs up front, is a simple one, according to Tsuji. "Both riders use the rear brake, but not often enough to keep it warm if it is made of carbon," he explains. "So we must use a steel disc for immediate response-and because we are already on the limit, the extra weight is not a problem."
Honda RC212V
Work In Progress
Honda had a reminder of how easy it is to fall from the top in MotoGP's debut 800cc season. After regaining the championship courtesy of Nicky Hayden aboard the 990cc five-cylinder RC211V, it took 10 races for Honda to finally score a win in 2007 with its troubled V-four successor, the RC212V. Honda riders unexpectedly struggled, scoring just four podium finishes in the first five races in a season that everyone from company president Takeo Fukui-himself a former HRC engineer-on down at Honda will surely want to forget.
The day after Repsol Honda's Dani Pedrosa at least ended the '07 season on a somewhat positive note by winning the final GP of the year at Valencia, Spain, Honda conducted a PR event so unwieldy that the horde of many ex-racers, TV commentators, journalists and media figures invited to ride the Hayden and Pedrosa bikes were each rationed to just three laps of the short Valencia track (the fact that engine life was reputed to have been cut back to 300km after Hayden's engine dropped a valve two races earlier during the Australian GP surely didn't help). This meant everyone got just a taste of the bike that most HRC executives would probably like to carve up with a bandsaw and throw in a dumpster anyway. Even the cursory technical briefing Honda gave before the ride was essentially worthless, with barely any meaningful information divulged in contrast to previous years.
Just as with Stoner's Ducati the following day, I was given the "honor" of first-riding duties on Hayden's bike early that morning, which meant I would be doing those measly three laps on new, unscrubbed tires on a cold track. Naturally the new Michelins took ages to warm up to working temperature in the chilly conditions, not helped of course by my slower pace compared with Hayden's. So it took me two laps before I began to feel comfortable on a bike that-even with the more spacious ergos for Hayden, compared with the diminutive Pedrosa-seems incredibly small and compact with a 56.7-inch wheelbase allegedly identical to the 990cc V-five, presumably to give stability in fast bends and help keep the front end weighted. The RC212V definitely feels a lot shorter and certainly more nervous.
It took me awhile to come to terms with the surprisingly fierce response of the Honda's full ride-by-wire throttle (which replaces the previous so-called "dual control system" modular layout used on the V-five). The engine mapping Hayden opts for verges on explosive and is in complete contrast with the more controlled initial pickup of Stoner's Ducati I rode later.
The electronic settings can be fine-tuned individually by the rider via a maze of buttons and switches. On the Honda's busy left clip-on, there's a three-position switch that gives you a soft/medium/strong choice of combined traction control and antiwheelie settings, as well as a button for scrolling through the readings on the digital dashboard panel to the right of HRC's trademark analog tachometer-then there's the separate pit-lane, speed-limiter button and the front brake lever adjuster knob. On the right handlebar there's another three-position switch, this one controlling deceleration by changing engine-braking control via the variable-idle-speed setting that adjusts according to gear ratio and other parameters. My riding time was too short to start playing around with the settings to see how much of a difference they made, but presuming the deceleration program was the same one Hayden used the day before in the race, he still likes a fair bit of engine braking dialed in, as befits a former Superbike champion.
The Honda engine is pretty shrill and raucous-sounding compared with the V-five, using the latest of 10 different exhaust layouts HRC tried last season matched to at least five different engine specs in the development rush to get back on terms with the competition. Judging by the way Pedrosa blasted past Stoner's Ducati down the front straight the day before en route to victory, the unstinting efforts of HRC's engineers to claw back the Ducati's horsepower advantage seem to have paid off. It's important to rev the engine right out to somewhere near the 18,800 rpm rev limiter, though-at least 1000 rpm higher than at the start of the season, when Honda was forced to reduce engine speeds due to consumption issues with the new 21-liter fuel tank limit. The blue shifter light flashes at 18,600 rpm to give you a wake-up call, and it pays to wait until you see it before upshifting, not only because power keeps on building all the way to the limiter, but mainly because the wheelies will get higher and longer if you short-shift any earlier.
The European race technician who handed the bike to me in pit lane said, "Nicky don't use clutch," and I noticed when setting off that the clutch had a very sudden pickup just as it engaged. That was the last time I used it until I returned to the pit lane five minutes later. The Honda gearbox worked flawlessly, shifting up or down without using the clutch with no jerks or hiccups as on other bikes where I've been told to forget about working the clutch lever once on the move. Even braking hard and downshifting three gears in swift succession for turn one as I started my faster final lap didn't faze the system, with the Honda's electronics ensuring the bike stayed stable and planted without snaking around. Not having to worry about the clutch meant I could use more concentration on other tasks, such as dealing with the very responsive Brembo carbon brake setup that Hayden prefers. The electronic engine-braking system is a pretty liberating function that allows you to focus more on your riding.
While it certainly seemed pretty nervous on my one and only reasonably hard lap, there's no denying the RC212V's nimble handling. A factor in this might be the vestigial fairing, supposedly minimalized to allow it to change direction from side to side more easily at speed. There is also the continued mass centralization development of the bike that surely contributes here, although Hayden and Pedrosa have complained that the concept might have been taken too far, with the RC212V suffering from excessive weight transfer under acceleration and braking. The bike definitely felt nervous climbing up and over the hill into the final turn, where it seemed that steering was very much a function of throttle and power as well as input at the clip-ons; differences in throttle setting affected steering a lot more than usual. This is a bike that in its present guise requires a lot of precision in the way it's ridden.
But Honda has been in this situation of not quite getting it right the first time before. In 1984 Honda unveiled its first ever V-four two-stroke GP racer, the NSR500. With its initial layout featuring the fuel tank beneath the engine and exhausts running over the top, the NSR struggled with teething problems, hindering the title defense of Honda's then World Champion, American Freddie Spencer (kind of sounds a little familiar, doesn't it?). But Honda responded the following year by completely redesigning the NSR500 along more conventional lines-and was rewarded with seven GP wins for Fast Freddie and a convincing world title victory that answered all its critics, as well as putting the NSR500 on the path to becoming the most successful 500GP racer of the two-stroke era.
Could history be about to repeat itself in 2008? We'll see.
Photo Gallery: Ducati, Yamaha, Honda - MotoGP Rides - Special Section - Sport Rider Magazine (http://www.sportrider.com/features/146_0804_motogp_ducati_yamaha_honda)
http://images.sportrider.com/features/146_0804_01_s+motoGP_rides+ducati_desmosedici_GP7. jpghttp://images.sportrider.com/features/146_0804_02_s+motoGP_rides+ducati_desmosedici_GP7. jpg
Read More (http://www.sportrider.com/features/146_0804_motogp_ducati_yamaha_honda) | Digg It (http://digg.com/submit?phase=2&url=http://www.sportrider.com/features/146_0804_motogp_ducati_yamaha_honda&title=Ducati Desmosedici GP7, Yamaha YZR-M1, Honda RC212V - MotoGP Rides - Special Section) | Add to del.icio.us (http://del.icio.us/post?url=2&url=http://www.sportrider.com/features/146_0804_motogp_ducati_yamaha_honda&title=Ducati Desmosedici GP7, Yamaha YZR-M1, Honda RC212V - MotoGP Rides - Special Section)
More... (http://www.sportrider.com/features/146_0804_motogp_ducati_yamaha_honda)
http://images.sportrider.com/features/146_0804_01_z+motoGP_rides+ducati_desmosedici_GP7. jpgDucati Desmosedici GP7
Casey's Cannonball
Let's face it: We all like it when the little guy wins. When the underdog upsets the odds. When ingenuity, passion and determination all pay off-including the foresight to gamble on building a bike like the Ducati Desmosedici GP7.
The chance to ride Casey Stoner's bike at the annual promofest press test after the Valencia GP promised to give at least the hint of an answer as to how the modern-day David triumphed over Goliath. Only one thing was wrong-well, two, actually. A crowd of people slated to ride the Ducati meant each person was limited to only four laps on the GP7. And to top it all off? "We know the track conditions aren't so good first thing in the morning after the overnight cold, so we need an experienced pair of hands to start the test," said Ducati PR exec Federica de Zottis. "You're up first!"
Well, of course I did as I was asked, rather than spit the dummy-wouldn't you? But this glimpse of the promised land was doubly frustrating because the Ducati is so different from all the other bikes. For a start it has quite different architecture from its Japanese rivals, being longer, lower and more voluptuous to look at. The seat is much lower than on the others, but it has a very distinctive riding position with extremely high footrests plus a wide and flat angle to the clip-on handlebars, where I'd expected steeply dropped clip-ons befitting someone from the 125/250GP classes like Stoner. "Don't forget, I'm a dirt-track graduate. That's where I learned how to race back home in Oz as a kid," Stoner explained about his bar angle.
After climbing aboard and settling into the hot seat I found the ergos to be surprisingly spacious, except for those high footpegs. They made the race-pattern gearbox quite hard to backshift on because of the raised lever that's also lifted to stop it from grounding at full lean. (According to telemetry graphs Stoner frequently leans over as far as 60 degrees from vertical.) Firing up the GP7 on the rollers produced a glorious sound from the twin 2-into-1 exhausts. The "screamer"-firing-order engine used this year has allowed Ducati to revert to these, in contrast to the four separate megaphones required by the old "Twin Pulse" 990. The lumpy, offbeat, 3000-rpm idle speed is deliberately set high to help offset engine braking when you close the ride-by-wire throttle entering a turn.
The fact that you can't easily read the tachometer isn't important, because the Ducati's broad spread of power makes it almost unnecessary. I expected the GP7's delivery to be quite peaky and the powerband relatively narrow, in pursuit of that all-conquering performance-but if anything it was quite the opposite. Though it doesn't pull quite as strongly from down low as the Suzuki and Kawasaki, the Ducati accelerates very hard from around 11,000 rpm onwards. There's a meaty spread of midrange power as it builds furiously toward the 19,000-rpm rev limiter dialed in for this press test (20,000-plus rpm in race guise has been rumored). A row of blue lights starts flashing at 18,500 rpm to tell you now might be a good time to upshift, as the Ducati accelerates like a missile while the Marelli anti-wheelie program stops the front wheel from lifting more than a few inches off the ground.
What about the traction control? Well, that only works when you're riding the bike the way it should be ridden. In just four early morning laps I'll admit that in right-handers I wasn't prepared to give it the berries because of concern about tread temps on that side of the tire. Valencia's numerous left-handers were another matter, and there I could revel in the Desmosedici 800's fantastic drive as the Marvel 4 ECU's electronics played a silent part in hooking up the rear tire. Just as when I rode Troy Bayliss' factory V-twin Superbike back in the summer of 2007, there's no sense that ignition advance is being held back or fueling leaned off, or that some unseen hand is winding back the GP7's throttle without your knowing it. There's no machine-gun stutter like Ducati's Superbikes once made, either-just a sense of unseen control that brings confidence in its wake.
But perhaps the biggest surprise in riding the Ducati GP7 is how smooth the response is when you get back on the gas again to drive out of a turn after using the monster power of the Brembo carbon brakes and the effective ramp-style slipper clutch to run deep into the turns. The electronics do their bit in softening the initial response-but only that. While there's none of the fierce power delivery from a closed throttle that the exhaust's raw-edged roar would lead you to expect, that doesn't mean that acceleration is anything less than awesome when you get the GP7 straightened up and fired out of the exit of the turn. Instead, once again the Ducati is simply well controlled. Ducati Corse engineers have cleverly mapped all the electronics to make the GP7 incredibly user-friendly for such a powerful motorcycle. There are myriad adjustments possible, but with just four laps I wasn't about to start playing around with the range of different settings for traction control and engine maps accessible by punching buttons in the busy-looking cockpit.
It's hard to ignore the Desmosedici motor, but as Stoner repeatedly proved it's the overall package that delivers the goods. The Ducati seemed to change direction better than all but the Honda, especially in the two Valencia chicanes where it flicked from side to side much more eagerly than its 990cc GP6 predecessor. And where that bike pushed the front wheel rounding the long left up over the hill leading into the last turn, the 800cc GP7 held a tight line much better. It needs to be kept hard on the gas to do this, but there's no doubt this is a better-steering bike than its predecessor.
I thought before I rode it that the Desmosedici GP7 would be all motor, or that maybe, as a certain Italian rider insists, the Ducati only won the world title because of Bridgestone's superiority or the GP7's high degree of electronic control that makes the pilot less important, F1-style. But it's easy to see it was all that plus Stoner's skill in riding the GP7 exactly as it needed to be ridden, as well as his newfound consistency in finishing every race, thanks mainly to a front tire he could trust. The Ducati GP7 is a bike that is beyond criticism from anyone except its regular rider. Only on tight, twisty tracks like Sachsenring and Valencia was it anything other than totally dominant; and judging by Stoner's times in Valencia testing the day after my ride, the GP8 that's been on track since March may very well have addressed that. Will 2008 be the start of a Ducati dynasty in MotoGP under the 800cc formula, like the Italian marque enjoyed in World Superbike for so long?
Ducati Desmosedici Gp7-How And Why
The man primarily responsible for creating the MotoGP title-winning Ducati GP7 is 39-year-old Filippo Preziosi, the direttore generale of Ducati Corse since 2005. Preziosi was the racing subsidiary's technical director starting in 2000, heading up engine and electronics R&D for both Superbike and MotoGP race projects. When Ducati announced it was entering MotoGP with a V-four-powered prototype, the big engineering decisions regarding the Desmosedici's layout and detail during development fell upon his shoulders.
"We at Ducati were very opposed to the change of rules from 990cc to 800cc for MotoGP, because that means you have to throw away your old engine and build a completely new bike, which costs a lot of money," Preziosi recalls. "Our company is a small one, our resources are limited, so for us it would have been much better to keep what was already working well. We needed to understand what in the GP6 was working correctly and try not to change any of that. So we concentrated only on what was absolutely necessary to change in going to 800cc.
"We decided to keep several parts. For example, we kept the front end of the bike: the front fork, the rims, brake calipers and so on. And we did the same thing with the rear; we kept the swingarm, the link, the shock absorber, the brakes, wheels, we kept everything more or less exactly the same. We also kept the same clutch from 2006; it was working properly, so we didn't find any reason to change it, and the same was true for the gearbox. The torque of the engine is greater on the 990 than the 800, but there are some differences in the firing order, so that made us think we should keep the same transmission. Just because you have a smaller-capacity 800cc engine, you might think that because the power and torque will therefore be less, you can make a smaller, lighter gearbox. But in reality, the power you are using is limited by the vehicle dynamics, not by the engine. So even if you have a 990 with more power and more torque, at the end of the day the power you are using when you are exiting the corner in third gear is the power allowed by the dynamics: wheelies, tire grip and so on.
"The marketing people at Ducati were not at all happy with the way we designed the GP7," Preziosi reveals, "because we kept more or less the same bodywork as the GP6, and that means it's more or less the same fairing as the GP3! Because people were expecting a big difference from 990 to 800, a lot of journalists were upset that we designed the GP7 bodywork to be so similar to the GP6. But the main point for a racing bike is to be fast, not to be different, so we tried to concentrate our efforts to have a faster bike, not a different bike."
Obviously the engine is where the majority of development was concentrated. "So we started to think what was the best configuration, with how many cylinders and how they should be arranged," says Preziosi. "We absolutely did not commit to simply downsizing the existing Desmosedici motor-all options were open. We did many simulations, but at the end of the day the answer was the same. We think that the 90-degree V-four is the best configuration, not only for engine performance, but also the entire layout of the bike. The mass is very concentrated, the internal balance of the engine is very good, the weight distribution of the motorcycle is what we are searching for, and the fuel consumption is under control, and the engine is very efficient."
Petroleum giant Shell also played a significant role in the Desmosedici's design. "In creating the new engine, we worked very closely with our partners at Shell. We relied on them to help deliver the efficiency that was so important for the kind of bike that we were planning to build, and that meant working on the fuel and oil side as well as the mechanical design. The first key ingredient of this was to reach high revs in order to achieve high power figures. With the 990 the power was not so important, because the performance was more defined by the vehicle dynamics; if the front wheel isn't touching the ground, there's no reason to have more power. But moving from 990 to 800, it seemed that output would be less, so the amount of power compared to our rivals would be more important, in which case the easiest way to reach more power is to increase revs. But unfortunately there are a lot of problems in doing that, and the first one is that fuel efficiency becomes an issue, so you have to make some decisions to avoid fuel consumption getting too high, especially with the smaller 21-liter fuel tank introduced for this season. We worked a lot on engine fluid dynamics to resolve this problem.
"The second key decision was to keep the screamer firing order," Preziosi continues. "This was completely the opposite compared to the rest of the MotoGP paddock, where technicians, riders, mechanics, journalists, everyone all insisted the screamer engine was too aggressive, that rideability was the most important thing in the world. We're fighting with Valentino Rossi, who is seven times world champion, we're fighting against Honda, who are 14 times world champion, we're fighting against Michelin, who are 26 times world champion. So if we choose to follow the same way as them, there is no chance to win. Ducati has to change something; we have to do things differently. So we felt this was the right choice. We thought that with the high revs and the screamer firing order, we could get more power, and that fuel consumption wasn't going to be an issue because the engine was more efficient. Of course, if Casey was not the Casey we know and admire so much, maybe we would have had a very bad season, and now I would have had to apologize for making the wrong choice! But thanks to Casey we're laughing and I can tell you how intelligent we were!"
During chassis development with the GP7, Ducati engineers made a surprising discovery. "On the chassis side, we believed our 990 GP6 had some problems, and we worked a lot on the frame to try to understand where these came from," Preziosi explains. "Loris complained the bike was not so stiff; he said there was some delay in its response. So we studied this a lot and eventually realized the problem was not on the chassis itself but on the stiffness of the footrest hangers! As you know, when you ride a bike you steer it not only with the handlebars, but also by shifting your body weight on the footrests. So in creating the GP7 we extended the concept we introduced in 2003, making the engine the central part of the motorcycle. Usually in every MotoGP bike the engine is a stressed component of the rolling chassis, so without the engine the wheel-to-wheel stiffness is less. But on the GP7 the engine is a part of the frame, so it's not possible to place the two wheels on the ground without it. This allows us to have a different structure with less weight, and the rear section of the frame is now a lot different to the GP3-GP6, with a carbon-fiber subframe that makes a really stiff structure, and the footrest hangers are now well supported."
Preziosi then reveals how much a role electronic rider aids now play in MotoGP. "We did a lot of work during the 2007 season on the electronics management and continued improving the electronics race by race, just as we did in 2006. The hardware is basically the same; we just changed the software strategy we wanted to apply for the 800 against the 990. The main point of the electronics was to improve rideability, because the specification we decided on for the engine was very good in delivering power, very good in fuel efficiency, but maybe not so good in rideability. This meant we just did different things with the same hardware for the GP7, because this is something very easy and cheap to do. If you have a good idea lying in bed at night, and you put the idea on the software in the morning, look at it in the system and you find that it's working well, you just have to use the ADSL connection to send it to Sepang or Le Mans or wherever the team is, and they can test it and find they have a different bike. With this kind of electronic management we can practically make a different bike with the same hardware for every track, for every rider, for every corner, in every weather condition. We can have a lot of different bikes in the same bike!"
Fiat Yamaha YZR-M1 800
Racing Relativity
The chance to ride Valentino Rossi's Yamaha YZR-M1 at Valencia after a season that saw him finish outside the top two championship places for the first time since his debut year in 125 Grand Prix back in 1996 was even more of an honor than usual, as I was one of just five journalists invited to do so. Ten laps on the bike not only made it a proper test rather than a showbiz stunt, it also allowed me to learn a lesson in two-wheeled relativity. Although everyone (including myself) who rode the Yamaha and Ducati proclaimed the YZR-M1 to be much easier to ride and a more complete package, the results column and Rossi's constant complaints regarding the Yamaha's lack of speed obviously showed how different things are when ridden at title-contending pace.
The two bikes could hardly be more different to sit on. While the Ducati is low-slung and stretched out, the more compact Yamaha has a much taller ride height. Asking Rossi's legendary race engineer Jerry Burgess why it was set up that way yields an interesting explanation. "It's because a couple of hours into the project, when Valentino was riding the Yamaha for the first time four years ago, we replaced the small 290mm discs they were using back then with bigger 320mm ones to get it to stop," Jerry recalls. "But then he complained he was locking the front brake, so it was obvious the low center of gravity the Yamaha had back then didn't work in delivering sufficient weight transfer under braking to load up the front wheel so the tire could grip. One way to deal with that is to lift the engine in the frame, or else you can just run the bike higher at both ends, which is what we did then as a quick fix and have done ever since."
The uncluttered cockpit has a white toggle switch on the left clip-on allowing you to scroll through the three different engine maps carried within the Magneti Marelli ECU, with a yellow launch control button above that for starts and the front brake lever adjuster knob just behind. These are matched on the right handlebar by the red kill-switch button, surmounted by a green one to press for the pit lane speed limiter, while the dash has last lap and best lap times prominently shown, plus an abbreviated analog tachometer display. But these are quite small because Rossi and teammate Colin Edwards II shift entirely by sound and feel, as well as the half-dozen small shifter lights which start flashing in unison at 18,300 rpm, followed by the bright-red shift light above them 500 rpm later before the harsh 19,000 rpm rev limiter. There's also a large gear indicator in the top right-hand corner of the dash, which is really welcome.
The YZR-M1's gruff-sounding but easy-revving 800cc 16-valve DOHC engine is surprisingly flexible and forgiving, pulling strongly from as low as 9000 rpm, then building power fast and strong once past the five-figure mark. It's not as peaky as you might expect given the smaller engine displacement, and the delivery is pretty linear and tractable. However, the Yamaha has more of a wheelie tendency than even its 990 predecessor did, which is another surprise, especially given that its ride-by-wire throttle control program is much less abrupt than all its rivals-save for the Ducati, with which the Yamaha shares the same Marelli Marvel 4 ECU. Besides continually pointing the front end skyward in each of the first three gears the Yamaha would even pull a long, lazy fourth gear power-wheelie down the front straight, lofting the front wheel controllably six inches above the tarmac, seemingly without sacrificing much acceleration. Much of this happens if you don't wait for the small lights on the top of the dash to all flash together from 18,300 rpm upward, because you then end up grabbing a higher ratio before the torque curve peaks.
Despite the wheelie tendency, the Yamaha is really well rounded and user-friendly to ride, especially the smooth yet strong throttle response when you get back on the gas again exiting a turn. Unlike the more powerful 990 with its comparatively brutal power delivery, on the 800 you can get on the throttle harder while still leaned over, accelerating on the edge of the tire to maintain momentum. With the Yamaha's smooth but effective throttle response, you can keep up corner speed knowing that when you get hard on the gas again you're not going to spin the back wheel because of the 990's big hit of power.
While I thought the 990cc YZR-M1 was hard work a year ago to make major steering changes, the agility of the 800cc version in the turns is outstanding. It's even more nimble than the more minuscule Honda, but without sacrificing anything in stability when you squeeze hard on the slightly dead-feeling four-pad/four-piston Brembo carbon brakes in a desperate attempt to slow the bike down from high speed. The Yamaha stayed glued to the line I had chosen, and as with the 990 YZR-M1, you can feel there's just enough engine braking delivered by the combination of the mechanical slipper clutch and ICS variable-idle system as you back down through the gears in quick succession (while always using the clutch to do so, however, just as Valentino does).
Once again, as in the past, you have the feeling this bike was carefully improved and demandingly refined by an expert in the art of setup, resulting in a package so capable it's almost beyond criticism. But only, it seems, at press-tester speed, although let's not forget this bike won four GP races this past season. "It's a good package, for sure," Burgess says. "I believe we've got a very, very good-handling motorcycle. But what we need is a little more push from the engine, a little more grip from the tires and a lot better reliability from the motorcycle as a whole. You can't afford a single DNF these days; look at how Stoner scored points in every race this year, which is a great achievement by Ducati as well as Casey himself, and we've got to match that next season. When you get a valve-spring engine turning at 19,000 rpm, the valve lift you can use is compromised, and even though the spring component may be all right you need very special spring wire-and the mass of everything is critical. It also compromises your choice of camshaft design and engine characteristics, so for sure pneumatics is the way to go. But for 2008 our primary focus is to take the bike as it is but with a better, more dependable motor and stick Bridgestones on it without sacrificing any of the many good things it has about it already. If we can do that, it's up to Valentino to do the rest-and we all know that he can!"
Fiat Yamaha YZR-M1 800 Tech
Yamaha's R&D team, headed by YZR-M1 project leader Kouichi Tsuji, developed a contender for the new 800cc category that was substantially based on the previous 990cc bike, aiming to retain the advantages of its inline-four-cylinder format and especially the proven chassis design. Rossi struggled for much of 2006 with midcorner chatter problems that were only resolved with the introduction of a new Deltabox frame design with altered rigidity specs for the final five races of the 990cc era. "After we found a chassis that performed satisfactorily, we were reluctant to discard it for the new formula," says Yamaha race boss Masao Furusawa. "So we retained the same essential format and developed an engine which took many lessons from our final-version 990cc power unit."
The DOHC 16-valve, inline-four-cylinder engine's overall dimensions are naturally reduced compared with the 990, but the overall bore-and-stroke ratio is less oversquare than the bigger motor's ultrashort-stroke layout, according to Tsuji, to regain some of the torque sacrificed by the smaller displacement. The new engine is 3.5kg lighter and physically smaller than the 990, measuring 8mm narrower overall and 18mm shorter from the top of the cylinder head to the crankshaft, which is also 5mm closer to the swingarm pivot cast into the crankcases. The Nikasil cylinders carry two-ring aluminum pistons machined from solid metal, mounted on titanium conrods. As before, the aluminum crankcases are likewise machined from solid billet. The complexity of the CNC programming necessary to carve all these components from solid lumps of metal is obviously significant.
Yamaha retained the so-called "long bang" format of the 990cc bike on the 800cc motor, with the firing pulses on two cylinders closed up to around 60 degrees of crankshaft rotation, followed by a space of around 300 degrees before the next pair fire close together, intended to enhance traction and tire life. Like the 990, the YZR-M1 800 motor's crankshaft rotates backward, with an intermediate shaft located between the crankshaft and dry clutch. This is also fitted with weights to act as a counterbalancer, thus eliminating undue vibration resulting from the uneven firing order. The Termignoni titanium exhaust is now the only one on the MotoGP grid to be fitted with a silencer, because Rossi claims a loud exhaust robs him of concentration. Yamaha can afford the weight penalty this entails; the YZR-M1 800 weighs 328 pounds with oil and water (no fuel) just like its big brother did, 1kg more than the MotoGP weight limit-and for the same reason. "We need to be sure it is this way at the start of a race, since by the end when weight is checked, we will lose up to 0.8kg from tire wear and oil consumption," Tsuji says.
Yamaha used conventional valve springs in the engine for most of the '07 season with the belief that engine revs for the new-generation 800cc bikes would be limited by fuel consumption. "We believed that the new 21-liter fuel tank regulation would mean that engine speeds could not exceed 18,000 rpm without running out of fuel in a race," Furusawa admits, "and at these rpm it is still OK to use valve springs instead of a more complex alternative technology." This explains why Yamaha got smoked in the first race of the season at Qatar, when computer projections for fuel consumption caused them to back off engine speeds to 17,500 rpm, resulting in Stoner's D16 GP7 being timed at 202 mph down the Losail pit straight, against just 192.6 mph for Rossi's Yamaha. When it was discovered afterward that Rossi's bike still had more than a liter remaining in the fuel tank-against just a third of a liter for Stoner-Yamaha realized its mistake and raised revs to 18,000 rpm for the next race in Jerez, which Rossi duly won.
But even more revs weren't sufficient to keep up with the flying Italian bike that ran 209.4 mph versus the YZR-M1's 202.5 mph at Shanghai, where the Honda and Kawasaki were both faster, too. This forced Yamaha to accelerate development of a pneumatic-valve version of the motor, which debuted in postrace testing at Brno in August and was judged sufficiently promising for Rossi to race it two weeks later in Misano, only to DNF with a blown engine.
When a repeat failure occurred in testing in Japan, the decision was taken to park it on the sidelines for the time being, especially as Yamaha had by now developed a fourth version of the existing valve-spring motor, whose revs had been raised to 19,000 rpm without affecting fuel consumption and seemingly without any ill effects in terms of reliability. This proved a wise decision when Rossi won in Portugal using that uprated motor, delivering four percent more horsepower than at the start of the season.
The full ride-by-wire electronic throttle Yamaha introduced on the 990 last year is retained, but the lighter and more compact Magneti Marelli Marvel 4 ECU used this year delivers enhanced engine management that now includes the ability to alter engine mapping for every corner, as well as for each gear ratio selected. Tsuji confirms the ECU now recognizes each individual turn on the track, via an onboard GPS receiver. And most importantly, the Marelli ECU is now programmed to make extremely precise calculations for fueling the motor, which are thought to include the facility to automatically lean the engine out in any given corner to save fuel, before richening it up again for speed down the straight, as Ducati is known to do via the same ECU.
Comparative telemetry from Jerez of relative performance between the 990 and 800cc Yamahas showed that on the smaller bike, Rossi brakes 30 meters later and opens the throttle 15 meters earlier than on its more powerful predecessor, using about 10 percent more throttle overall than on the 990. And while this had a 3-5 percent faster top speed-about 6 mph quicker down a long front straight like the one at Mugello-the 800 is anywhere from 2-6 mph faster in turns. This underlined the critical ingredient of chassis design in creating the new bike. "The YZR-M1 frame is designed to keep the vertical stiffness and reduce lateral stiffness and torsion," Tsuji explains. "This is because when the bike is banked, the frame must also act as suspension. That is why we focus very much on this element with many tools and simulations, and why in 2005 we removed the cross-member of the frame. This reduced lateral and torsion stiffness and gave much improvement for agility and stability."
After thick 47mm Ohlins forks were also debuted at Mugello in an effort to give Rossi better feel during braking, overheating problems resulted from the big forks cutting off cooling airflow to the radiator. A new fairing was introduced at Brno to fix this, and that's what was on the bike at Valencia. The long swingarm delivers not only enhanced stability and traction in what is understood to be a relatively short wheelbase by current MotoGP standards, but also helps improve grip from the front 16-inch Michelin adopted this season, mated to a 16.5-inch rear. The reason for using a 220mm ventilated steel disc at the rear, in contrast to the big 320mm carbon discs up front, is a simple one, according to Tsuji. "Both riders use the rear brake, but not often enough to keep it warm if it is made of carbon," he explains. "So we must use a steel disc for immediate response-and because we are already on the limit, the extra weight is not a problem."
Honda RC212V
Work In Progress
Honda had a reminder of how easy it is to fall from the top in MotoGP's debut 800cc season. After regaining the championship courtesy of Nicky Hayden aboard the 990cc five-cylinder RC211V, it took 10 races for Honda to finally score a win in 2007 with its troubled V-four successor, the RC212V. Honda riders unexpectedly struggled, scoring just four podium finishes in the first five races in a season that everyone from company president Takeo Fukui-himself a former HRC engineer-on down at Honda will surely want to forget.
The day after Repsol Honda's Dani Pedrosa at least ended the '07 season on a somewhat positive note by winning the final GP of the year at Valencia, Spain, Honda conducted a PR event so unwieldy that the horde of many ex-racers, TV commentators, journalists and media figures invited to ride the Hayden and Pedrosa bikes were each rationed to just three laps of the short Valencia track (the fact that engine life was reputed to have been cut back to 300km after Hayden's engine dropped a valve two races earlier during the Australian GP surely didn't help). This meant everyone got just a taste of the bike that most HRC executives would probably like to carve up with a bandsaw and throw in a dumpster anyway. Even the cursory technical briefing Honda gave before the ride was essentially worthless, with barely any meaningful information divulged in contrast to previous years.
Just as with Stoner's Ducati the following day, I was given the "honor" of first-riding duties on Hayden's bike early that morning, which meant I would be doing those measly three laps on new, unscrubbed tires on a cold track. Naturally the new Michelins took ages to warm up to working temperature in the chilly conditions, not helped of course by my slower pace compared with Hayden's. So it took me two laps before I began to feel comfortable on a bike that-even with the more spacious ergos for Hayden, compared with the diminutive Pedrosa-seems incredibly small and compact with a 56.7-inch wheelbase allegedly identical to the 990cc V-five, presumably to give stability in fast bends and help keep the front end weighted. The RC212V definitely feels a lot shorter and certainly more nervous.
It took me awhile to come to terms with the surprisingly fierce response of the Honda's full ride-by-wire throttle (which replaces the previous so-called "dual control system" modular layout used on the V-five). The engine mapping Hayden opts for verges on explosive and is in complete contrast with the more controlled initial pickup of Stoner's Ducati I rode later.
The electronic settings can be fine-tuned individually by the rider via a maze of buttons and switches. On the Honda's busy left clip-on, there's a three-position switch that gives you a soft/medium/strong choice of combined traction control and antiwheelie settings, as well as a button for scrolling through the readings on the digital dashboard panel to the right of HRC's trademark analog tachometer-then there's the separate pit-lane, speed-limiter button and the front brake lever adjuster knob. On the right handlebar there's another three-position switch, this one controlling deceleration by changing engine-braking control via the variable-idle-speed setting that adjusts according to gear ratio and other parameters. My riding time was too short to start playing around with the settings to see how much of a difference they made, but presuming the deceleration program was the same one Hayden used the day before in the race, he still likes a fair bit of engine braking dialed in, as befits a former Superbike champion.
The Honda engine is pretty shrill and raucous-sounding compared with the V-five, using the latest of 10 different exhaust layouts HRC tried last season matched to at least five different engine specs in the development rush to get back on terms with the competition. Judging by the way Pedrosa blasted past Stoner's Ducati down the front straight the day before en route to victory, the unstinting efforts of HRC's engineers to claw back the Ducati's horsepower advantage seem to have paid off. It's important to rev the engine right out to somewhere near the 18,800 rpm rev limiter, though-at least 1000 rpm higher than at the start of the season, when Honda was forced to reduce engine speeds due to consumption issues with the new 21-liter fuel tank limit. The blue shifter light flashes at 18,600 rpm to give you a wake-up call, and it pays to wait until you see it before upshifting, not only because power keeps on building all the way to the limiter, but mainly because the wheelies will get higher and longer if you short-shift any earlier.
The European race technician who handed the bike to me in pit lane said, "Nicky don't use clutch," and I noticed when setting off that the clutch had a very sudden pickup just as it engaged. That was the last time I used it until I returned to the pit lane five minutes later. The Honda gearbox worked flawlessly, shifting up or down without using the clutch with no jerks or hiccups as on other bikes where I've been told to forget about working the clutch lever once on the move. Even braking hard and downshifting three gears in swift succession for turn one as I started my faster final lap didn't faze the system, with the Honda's electronics ensuring the bike stayed stable and planted without snaking around. Not having to worry about the clutch meant I could use more concentration on other tasks, such as dealing with the very responsive Brembo carbon brake setup that Hayden prefers. The electronic engine-braking system is a pretty liberating function that allows you to focus more on your riding.
While it certainly seemed pretty nervous on my one and only reasonably hard lap, there's no denying the RC212V's nimble handling. A factor in this might be the vestigial fairing, supposedly minimalized to allow it to change direction from side to side more easily at speed. There is also the continued mass centralization development of the bike that surely contributes here, although Hayden and Pedrosa have complained that the concept might have been taken too far, with the RC212V suffering from excessive weight transfer under acceleration and braking. The bike definitely felt nervous climbing up and over the hill into the final turn, where it seemed that steering was very much a function of throttle and power as well as input at the clip-ons; differences in throttle setting affected steering a lot more than usual. This is a bike that in its present guise requires a lot of precision in the way it's ridden.
But Honda has been in this situation of not quite getting it right the first time before. In 1984 Honda unveiled its first ever V-four two-stroke GP racer, the NSR500. With its initial layout featuring the fuel tank beneath the engine and exhausts running over the top, the NSR struggled with teething problems, hindering the title defense of Honda's then World Champion, American Freddie Spencer (kind of sounds a little familiar, doesn't it?). But Honda responded the following year by completely redesigning the NSR500 along more conventional lines-and was rewarded with seven GP wins for Fast Freddie and a convincing world title victory that answered all its critics, as well as putting the NSR500 on the path to becoming the most successful 500GP racer of the two-stroke era.
Could history be about to repeat itself in 2008? We'll see.
Photo Gallery: Ducati, Yamaha, Honda - MotoGP Rides - Special Section - Sport Rider Magazine (http://www.sportrider.com/features/146_0804_motogp_ducati_yamaha_honda)
http://images.sportrider.com/features/146_0804_01_s+motoGP_rides+ducati_desmosedici_GP7. jpghttp://images.sportrider.com/features/146_0804_02_s+motoGP_rides+ducati_desmosedici_GP7. jpg
Read More (http://www.sportrider.com/features/146_0804_motogp_ducati_yamaha_honda) | Digg It (http://digg.com/submit?phase=2&url=http://www.sportrider.com/features/146_0804_motogp_ducati_yamaha_honda&title=Ducati Desmosedici GP7, Yamaha YZR-M1, Honda RC212V - MotoGP Rides - Special Section) | Add to del.icio.us (http://del.icio.us/post?url=2&url=http://www.sportrider.com/features/146_0804_motogp_ducati_yamaha_honda&title=Ducati Desmosedici GP7, Yamaha YZR-M1, Honda RC212V - MotoGP Rides - Special Section)
More... (http://www.sportrider.com/features/146_0804_motogp_ducati_yamaha_honda)