Great Expectations - MotoGP Honda

A little-known fact (except by rabid race fans and readers of this magazine) regarding the Repsol Honda MotoGP team: The RC211V racebikes that World Champion Nicky Hayden and teammate Dani Pedrosa rode during the '06 season were not the same. While Pedrosa was riding what was basically an '05 211V with minor chassis and engine updates (even though HRC termed it the '06 Original version), Hayden was pressured to ride the heavily revised New Generation model featuring a completely new engine and chassis that was the basis for the company's latest RC212V 800cc MotoGP machine.

In short, Hayden ended up being a test rider of sorts. While MotoGP rookie Pedrosa and other Honda satellite team riders like Fortuna Honda's Marco Melandri and Toni Elias quickly grabbed victories during the season on the well-sorted '05 RCV, Hayden struggled with a number of teething problems on the '06 model (the most publicized being a recalcitrant clutch that wasn't fixed until the penultimate round in Portugal) that nearly undermined his ultimately successful championship campaign. Interestingly, HRC officials admitted at the fourth round of the '06 MotoGP championship (held at Shanghai, China) that the New Generation model was brought into service a little prematurely and that it didn't yet have the potential to win races-this before admitting later in the year that Hayden had been riding the bike from the season's start.

Thus we flew into Valencia after the final GP of the season eager to sample the same machine that took Hayden to the title. Unfortunately, Honda Europe apparently had a large number of people clamoring to ride the bike, and for various reasons we were stuck with riding Pedrosa's updated '05 machine. Beggars can't be choosers, however, so we weren't exactly going to pass on the opportunity. With '06 being the last year for the 990cc RC211V in any form, yours truly was still glad to have the chance to ride the Honda before it shrank to the mandated 800cc displacement limit for '07.

Evolution Of The SpeciesIntroduced in '02, Honda's choice of a 75.5-degree V-5 engine configuration for the RC211V followed the company's typical penchant for different but innovative engineering. Instead of using a 90-degree V-angle for better primary balance like Ducati, Honda's narrower vee enabled HRC engineers more freedom to position the engine for optimum handling, while the fifth-cylinder throw acted as a counterbalancer, eliminating the need for a power-robbing secondary balancer. Another unique aspect of the engine was its semi-dry-sump oiling system; the crankshaft area is sealed off as a separate chamber, and a scavenge pump uses the transmission cavity as an oil reservoir. This setup offers numerous benefits over conventional wet- and dry-sump designs, including less pumping losses and blow-by into the combustion chamber, a more stable oil level and a stronger and more compact crankcase construction. The Unit Pro-Link rear suspension also made its debut, which featured the top shock mount encased in the swingarm instead of the frame.

The next-generation '03 RC211V featured 10 percent more power by way of combustion chamber, cam timing and other modifications, along with a higher rpm ceiling. To reduce engine compression braking during corner entry, ECU-controlled solenoid valves bled air past the throttle plates when the system detected rear-wheel lockup. The exhaust was changed from a twin-exit system to a triple-exit system, resulting in improvements in lower-rpm torque. Chassis-wise, the precursor to the HESD (Honda Electronic Steering Damper) found on current CBR production sportbikes made its debut, along with subtle changes to the chassis and swingarm aimed at better cornering feel, and aerodynamic revisions to the fairing.

With the introduction of the '04 RC211V, it's widely accepted (although never officially confirmed by HRC) that the engine went to a more oversquare configuration to boost power, resulting in a five-percent increase in top-end horsepower along with the side benefit of a five-percent reduction in fuel consumption. Overall power and torque characteristics were smoothed out with the switch from the previous 5-into-3 exhaust to a 5-into-4 exhaust system.

In an effort to control the ever-increasing power of the RC211V, HRC introduced the Honda Intelligent Throttle Control System, a semimechanical/electronic forerunner to the now-common fly-by-wire throttle systems on MotoGP bikes. The twist-grip throttle cables rotated a throttle linkage shaft attached to a tiny planetary gear setup controlled by an ECU-actuated servo motor. The system would modify the amount of throttle-valve movement according to the gear selected, preventing excessive power in the lower gears. However, it was widely rumored that many of the Honda riders disliked the system, complaining that it affected the engine power too much.

Chassis changes included a new "reversed" Unit Pro-Link design that switched the rear shock linkage from the bottom to the top of the swingarm, freeing up space down below for the exhaust and offering several load geometry advantages (see Art & Science, Sept. '04). More wind-tunnel work resulted in a more steeply canted windscreen, plus modified hand guards and ram-air intake duct areas that produced a front fairing with five-percent-better aerodynamics.