HONDA The Power of Dreams

Former Honda Racing Corporation (HRC) works rider Hikaru Miyagi: Since the Superbike World Championship changed its allowed displacement to 1,000cc, Honda decided the seventh-generation 2004 CBR model would become the base vehicle for that competition. So displacement on the specification sheet went up, and the new model received numerous advanced technologies directly from the MotoGP racing machine. I saw it as a model that took on competitors in a frontal attack. The name of the bike changed to CBR1000RR, and it became a model that did not entirely fit the pattern established by its predecessors.

Final assembly team leader Kyoichi Yoshii: That’s right. When the Superbike World Championship changed its spec to four cylinders and 1,000cc, we designed the new CBR with this competition in mind. Among the development team members, however, there were those who said that CBR bikes were not intended for racing. And yet, up until that point, riders had used CBR bikes not only for getting around town and sporty riding but also for racing. Taking that into consideration and the fact that we’d be adopting cutting-edge technologies from our MotoGP racing machine, we felt that there would be some substantial merits to the new approach.

Miyagi: The RC211V was an incredibly easy bike to ride. For a racing bike, that is, but it really was amazingly easy to handle, and it was comfortable, too.

Miyagi: There could be no greater source of inspiration than the RC211V, could there? The timing was really great for you to make all kinds of changes.

Yoshii: Whether you’re raising engine power or making other changes, you’ve got to adjust the entire body of the motorcycle to ensure total control. The RC211V provided us with the perfect image of how this is done. We had the chance to leverage this in a commercially produced vehicle and redesign the body, the engine and everything else. The other manufacturers were all offering 1,000cc super sport bikes of their own. So we thought that now was the perfect time to use our most advanced technologies and create a super sport bike in the Honda tradition on which riders could enjoy sporty riding with the highest level of enjoyment and peace of mind.

The switch from 2-stroke to 4-stroke engines in MotoGP meant that the new bikes had vastly different characteristics from the old, such as higher vehicle weight and increased engine braking. In order to give riders total control over the new 4-stroke bikes, it was necessary for manufacturers to rethink their design completely. Honda responded by pursuing at the highest level the characteristic that is perhaps the essence of a racing motorcycle—concentrated mass—and designed the body of its new bike to counteract the rear wheel sliding caused by strong engine braking. One technology that was crucial in the implementation of this vision was the new Unit Pro-Link rear suspension.

Fujita: If we’re talking about just the suspension, then using the Unit Pro-Link increases the weight of the swingarm and unsprung parts. But the benefit of the Unit Pro-Link was that the cushion unit didn’t need to be supported by the frame. This difference increased the freedom of frame rigidity, allowing us to create a design that prioritized rigidity in the pivot area of the frame.

Miyagi: I see. So we’re not talking about how just the suspension or frame works by itself but instead about a technology that has an effect on the entire finished vehicle. I guess that means that while you as the suspension designer had quite a tough time of it, the frame designers were extremely happy, right?

Fujita: Yes, without putting forth any effort, they got a more lightweight frame. [Laughs.] Even though the suspension gave us a tough time, the use of the Unit Pro-Link allowed the frame to be designed with a great deal more freedom. As a result, we were able to realize a higher level of turning performance and overall stability than ever before.

Fifth-generation CBR900RR (CBR929RR) Assistant LPL Kenji Hasegawa: In previous models, there was an upper cross-pipe to which the suspension was attached, but now the fuel tank could be positioned there, resulting in a greater concentration of mass and a more optimal moment of inertia.

Miyagi: This also connected with your goal of giving the 2000 and 2002 models a lighter riding feel without increasing rigidity. It’s true that the CBR1000RR was a bit heavier than its predecessors, but the greater freedom of frame design made possible a vehicle that had a lighter riding feel than one would expect from its weight.

Fujita: That’s correct.

Miyagi: In terms of new technologies on the CBR1000RR, the Honda Electronic Steering Damper (HESD) was fantastic. One day I borrowed the CBR1000RR used for PR at Honda’s Aoyama headquarters, and I got on the Metropolitan Expressway. This expressway has some rough patches, one has to look for gaps in the traffic flow in order to change lanes, and it just isn’t an easy road to ride on by any standard. I was really surprised that, even on this expressway, the CBR1000RR was so easy to ride that it didn’t feel like riding a high-powered super sport bike at all.

Seventh-generation CBR1000RR Large Project Leader (LPL) Hirofumi Fukunaga: It really makes me happy to hear you say that. We really wanted riders to be able to ride in any environment with peace of mind. And I was really proud that we were able to present the CBR1000RR as the most stable super sport bike in the world at high speeds and in the rain, and that riders could ride it with such peace of mind.

Styling that promises sharp riding. A wild and aggressive face, like that of a beast stalking its prey. The center-up exhaust pipe, moved from its traditional position to inside the tail cowl. The world of elite racing not only provided insights that helped the development team enhance performance; it also helped them take the looks of their creation to the next level. Deeply inspired by the RC211V, the CBR1000RR introduced riders to an entirely new world of style.

Miyagi: The center-up muffler was certainly stylish, but it had to have a lot of insulation around it, didn’t it? This has really stuck in my memory. The exhaust pipe is something that can get really hot, and since it’s located up high, you had to make sure that people couldn’t get burned. Even as you were struggling to make the whole machine light one gram at a time, you worked hard to ensure safety, which really made me feel Honda’s dedication in this area.

Final assembly team leader Kyoichi Yoshii: Our intention is to keep riders, owners and their families happy. With the performance of super sport bikes always going up, riders have come to be seen as these extreme people. But that’s not what we were going for at all. Our goal was to have more people understand motorcycles and have riders ride with greater enjoyment and safety.

Miyagi: Even though the tail cowl was so thin, you pulled off the huge feat of including a small storage compartment. Unlike the 900cc era bikes, there was no hinge, and there was only enough room for a U-lock, but I could sense you really wanted to include this feature.

Kishi: This feature of course was part of the roots of the CBR series, indicating that, from the beginning, the home of these bikes was on the street. Frankly speaking, when I was working on the clay model, I felt like just getting rid of it. [Laughs.]

Hasegawa: The center-up muffler had also several big benefits when it came to the motorcycle body as a whole. It contributed to an optimal left-right center of gravity offset, as well as to the bike’s aerodynamic characteristics. This may sound obvious, but it wasn’t just for looks. The person responsible for engine development said, “This thing is here just to look cool, and it has no real merit,” but he was able to use the longer exhaust pipe to good effect, and when we put the muffler down on the side again for the ninth-generation model, he complained that it was better when the exhaust pipe was longer. [Laughs.]

From single-cylinder to horizontally opposed 6-cylinder configurations, Honda offers a wide variety of powerplants in its motorcycle lineup. For its racing bikes as well, Honda makes V2, V4 and V5 and numerous other types of engines that have produced exceptional results on the track. Among all these possibilities, the design team selected an inline 4-cylinder engine for the CBR1000RR with specific objectives in mind.

Miyagi: Right, I understand what you mean. I clearly recall how, after the 1985 Suzuka 8 Hours Endurance Road Race, I borrowed an RVF750 from the Rothmans Honda team and took it for a spin. As compared to what I had been regularly riding, an air-cooled inline 4-cylinder Moriwaki CBX750F, I felt as though I could not slow down enough on the 130R turn on the Suzuka Circuit. The RVF750 with its V4 engine just produced much more speed than I expected. So I think a V4 has a role to play in a world-class 300 km/h race, and I think it can also be good in a tourer when you’re going a long distance in one go. But for enjoyable, sporty riding on the street, I think an inline-4 is the best.

Fukunaga: Yes, that matches our thinking exactly. That’s why we went with an inline-4 engine.