Can’t we all just get along? It seems that Ducati’s first world championship title has upset the major Japanese manufacturers a great deal. After Honda (rumor has it) got the FIM and MSMA to reduce the capacity to 800cc, they fully expected to be able to dominate the MotoGP class as they had after the previous change, like the switch to four-stroke engines in 2002. They had not reckoned on a tiny Italian factory stealing their thunder by gambling on maximum horsepower, and humiliating the big players, natural heirs to the MotoGP crown.

So it seems like the big players - or more specifically, Honda and Yamaha - have hit upon a quick way to neutralize the threat posed by Borgo Panigale: Honda and Yamaha are pushing for rev limits to be introduced in MotoGP. Under the scheme, engines would have an artificial ceiling set on the maximum number of RPM. More interestingly, the figure quoted is a maximum of 19,000 rpm. The fact that the Ducati is the only bike to rev above that number cannot be a coincidence: all of the other manufacturers’ powerplants stop revving at around 18,000.

For both Honda and Yamaha, any such rule would be a godsend, as Honda is struggling to get its pneumatic valve engine working, and is having to make do with the limits imposed on engine speeds by using conventional steel springs, generally thought to be around the 17-18 thousand rpm mark. The other proponent is Yamaha, who have struggled in the horsepower stakes ever since the inception of the four stroke era in MotoGP, and have had to rely on outstanding handling and the riding genius of Rossi to remain competitive. With limits on engine speeds, Yamaha would at least be chasing a target which has stopped moving quite so quickly.

Understandably, Ducati oppose the move. They feel, with some justification, that they are being penalized for using the natural advantages of the desmodromic system they have become synonymous with, despite only switching to the system some 50-odd years after its first use. Honda’s RC212V project leader, Shinichi Kokubu, cited costs as a reason for imposing rev limits, but Ducati’s engineer and the brains behind the GP8 project, Filippo Preziosi dismissed this argument. “I say since we are able to get this performance with a system that is fitted on a road bike like the Monster 695, the issue of costs doesn’t hold water,” he told the Gazzetto dello Sport.

Ducati are not alone in their opposition: Kawasaki are also against the limits. As the factory with the smallest budget in MotoGP, any such regulations would hit Kawasaki the hardest.

The proposed rule changes are unlikely to be accepted, as they would most likely require a unanimous vote of the MSMA, which comprises the motorcycle manufacturers involved in racing. But the proposal is an ominous sign. When Dorna CEO Carmelo Ezpeleta threatened to impose a single tire on MotoGP at the end of last year, he unwittingly opened a Pandora’s box, with manufacturers now seemingly willing to use rule changes as political bargaining chips for exerting pressure. But MotoGP’s problems should surely not be settled in the political arena, but out on the track. In a prototype series, rev limits surely have no place.

See related story…

It sounds like they’re talking about p…, they’re not but sound is part of it, it’s not easy to hide! Masao Furusawa, Yamaha’s general manager of Engineering Operations, likes listening to Kawasaki’s new screamer engine - but says the even-firing design will never again power a Yamaha MotoGP bike.

“We will never use a screamer engine again. Never!” said Furusawa, “We threw away the screamer engine in 2003.”

Furusawa, who has worked with Yamaha since the early 1970s, was put in charge of the YZR-M1 project upon Valentino Rossi’s arrival in 2004 - and one of the first major technical changes was the introduction of a ‘big-bang’ 990cc engine.

Following Yamaha’s example, the technology - previously seen in 500cc - was soon once again present throughout the premier-class field. However, last year’s change to 800cc engines saw Ducatiand then Hondareturn to a screamer, as maximum horsepower - the main advantage of a screamer - became a priority.

Whereas a screamer engine - so called due to its high-pitched engine note - features an equal amount of time between the firing of each cylinder, ‘big-bang’ engines have an uneven firing order.

So - in the case of a four-cylinder engine - two cylinders fire closely together (producing what sounds like one ‘big bang’), then there is a longer than usual time period before the other two cylinders are fired (also closely together).

Kawasaki’s development team rolled out the factory’s superb sounding new screamer during the January Sepang test, although it didn’t make a return appearance at last week’s outing, much to Furusawa’s disappointment.

“I hope Kawasaki brings it back! I like to listen to it. Their screamer is not here this time and honestly I don’t like it,” he smiled. “Please use the screamer engine!”

Nevertheless, Furusawa - who gave a detailed presentation on ‘big-bang’ at the season-ending Valencian Grand Prix- was happy to explain why Yamaha will be sticking with ‘big-bang’ for its grand prix prototype.

He describes the ‘big-bang’ effect in terms of a communication process between the rider and rear tire, made via the engine. A communication process which, in the case of a screamer design, becomes increasingly distorted at high rev/min. ‘Big-bang’ engines keep this distortion to a minimum.

“Internally the ‘big-bang’ engine is very smooth during its rotations. It sounds like it is fluctuating a lot, because of the uneven combustion timing, but the reality is that it is very smooth at high rpm,” he began.

“The screamer engine sounds very smooth, but over 12,000 rpm the motion of the moving parts inside the engine becomes a big problem. You can think of it as creating a big ‘noise’ that stops the rider from hearing what the tire is ’saying’ to him.

“The rider needs to listen carefully to the tire and talk to it directly with the throttle, but the screamer engine makes it really hard to ‘hear’. So the connection between throttle and tire is not good with the screamer - don’t explain this to the Kawasaki people!” he quipped. “I’m only joking!

“So the screamer engine sounds nice, but if the engine goes over 12,000 rpm then there are problems and in MotoGPthe useable rpm is 14,000 to 17,000 - sometimes up to 19,000 - so a big ‘noise’ is happening at high rpm with a screamer and the rider cannot ‘talk’ to the tire,” he concluded.

Yamaha and Kawasaki both use an inline four-cylinder layout for their MotoGP engines, while Ducati, Hondaand Suzuki use a V4 configuration.

The people in charge of the MotoGP decided the 990cc’s were too fast, so they cut the capacity to 800cc, reduced the fuel limit, but left the minimum weight the same. 148Kg for a four-cylinder.
And they go faster. There’s no mystery, really. All these big four-strokes have too much power, but the last season MotoGP bikes (990cc) had way too much torque as well. They were the ultimate in point-and-squirt. Muscle bikes, really.

The 2008 MotoGP season bikes (800cc) are both noisier and in some ways more exciting, but mainly much more refined. Where the last season 990cc MotoGP bikes fishtailed into the bends then laid big blackies out of them, the new bikes let riders arc in fast and smooth, using all the paint, as well as incredible angles of lean.

Valentino Rossi’s crew chief Jerry Burgess confirmed they are faster through a set of corners. It seems there has been some increase at the slowest point of the corners too, but possibly not as much as the eight or twelve km/h claimed by some, including Rossi, as well as Bridgestone tire engineers. Team Roberts technical guru Warren Willing, like Burgess, believes any increase has been small, and down to better tires and better general handling rather then any magic from a smaller engine.

All the same, through a set of corners, the speed is sufficiently higher to make up for the loss of top end. At pre-season tests this was almost exactly 10 km/h, with Ducati still the fastest, Casey Stoner trapping at 277.3 km/h.

Valentino Rossi explains: ‘the bike is better balanced. With the old bike it was a problem to put the power on the ground, although the sliding was enjoyable. But you couldn’t use the best line. Now we use all the track and one line, or another line” Hayden adds: “in certain areas, it’s more of a rider’s bike. I’m enjoying it more than the last season 990cc MotoGP bike.

Technically, the designers have also been able to shift the weight around, because the engines are significantly lighter, as much as six kilos in the case of the Kawasaki ZX-RR and about the same for the Honda. In many cases, says Jerry Burgess the last year 990c MotoGP bikes were overweight, and can now get closer to the minimum.

The biggest change ha come in tires. Bridgestone chief Hiroshi Yamada explains how with less torque the tire design brief has been skewed in favor of edge-grip, allowing higher lean angles. Michelin have even more ammunition, a new 16-inch front, was before 16.5 inch. With a smaller rolling diameter and a bigger contact patch this exploits the new-found agility, allowing later braking and faster corner entry.

Just one problem. As the engines shrunk by 20 percent, so also did maximum fuel tank size, from 22 to 21 liters. But the new 800cc MotoGP bikes are greedier than the old 990cc bikes. Riders open the throttle sooner and rev higher. Fuel consumption is a serious concern, hence a heavy emphasis on full race simulations in testing so far

Kawsaki cheif Ichiro Yoda said: ‘if we stick to 18,000rpm, we are alright, but if we want to increase, it will be difficult’.

With leads to a final surprise. With less torque to mange, the 2008 season 800cc MotoGP bikes actually have less electronics than before, reversing the trend of the past few years and returning more control to the riders.

Ducati technical director Filippo Preziosi has hit out at proposals put forward by Yamaha and Honda to introduce a rev limit for engines in MotoGP.

Talks about future changes to technical regulations were held between manufacturers at last weekend’s official MotoGP test at Jerez, and one idea being discussed is for MotoGP engines to be limited to 19,000rpm.

But with Ducati likely to be the only manufacturer to suffer as a result of such a change, Preziosi has suggested the plans are being designed to hamper their team on the back of their dominant 2007 campaign - rather than reduce costs or improve safety.

“Well, (we may as well) say that Italian bikes ridden by Australian riders are barred from taking part in MotoGP,” Preziosi told Gazzetta dello Sport. “In fact, since in Superbikes we won only with Australians and Britons, I’ll add the latter ones too. What a coincidence this limitation is…

“I say since we are able to get this performance with a system that is fitted on a road bike like the Monster 695, the issue of costs doesn’t hold water. If then we talk about safety, riders haven’t crashed on the straights for years, they crash in turns, so top speed doesn’t have anything to do with it.

“I have too much respect for the Japanese to believe they really want to go forward with these projects.”

Preziosi’s criticism of the idea to introduce rev limits has been supported by Ishiro Yoda, Kawasaki’s technical director.

He told Gazzetta dello Sport: “By bringing the engine displacement to 800cc it was said that the regulations wouldn’t be changed for five years. We’ve already spent plenty of money to re-do the bikes, and there’s no point in spending more.

“The aim was to slow down the bikes on the straights, and the 800cc are slower there, even though the lap times decrease. To limit the number of engine revolutions doesn’t make sense.”

Honda’s Shinichi Kokubu, project leader of the RC212V at HRC, made it clear that he was fully supportive of the idea.

“As an engineer, I say that limiting the engine revs could be a way if we want to limit the costs of our bikes. I think that 19,000 revolutions would be a fair limit,” he said.

Welcome to our new engine building section. As you can see it’s so new we have yet to post an article, we’ll start soon. Our first articles will discuses the benefits and hazards of timing. Thanks for your patients….TRS