The new 800cc MotoGP racers are testing again, this time at the Sepang Circuit in Malaysia. Suzuki’s John Hopkins and Yamaha’s Colin Edwards both did laps today that were quicker than the 2006 fastest race lap, set by Ducati’s Loris Capirossi – yet again showing that the 800s aren’t giving up any speed when compared to the 990cc machines they are replacing.
As Dirck discussed in his article Why Are The 800s So Quick?, one of the main reasons the new bikes are circulating the track so fast is that they are capable of carrying significantly higher corner speeds than the 990s – mainly because the rotating mass of their smaller-displacement engines is much lighter.
So what does this tell us? In a situation where two race bikes each have similar usable power (the extra power the 990s possessed could only be applied on longer straights), the bike with the lighter reciprocating mass (crankshaft, etc.) will be as fast or faster around the racetrack, due to its ability to carry more corner speed.
How does this apply to street-legal, mass-production sportbikes, you ask? The power output of production sportbikes is steadily increasing every year, with each manufacturer straining to outdo the others – and the 1000cc inline-fours produced by the Japanese companies are already producing significantly more power than is usable by the average rider under most circumstances, especially when they are riding their sportbike as it was designed to be ridden (i.e. on a twisty road, not a straight freeway onramp). With most of the Japanese OEMs rotating their engineers regularly between the racing and street departments, could an engineer fresh from the 800cc development team apply the concept of better performance through lighter reciprocating weight to his company’s street line-up?
Suzuki is the only manufacturer who has defied the predicted demise of the 750 class and continued to produce their GSX-R750, although the latest bike carries over many parts from their 600. Still, strong sales of the middle GSX-R means that buyers can appreciate the combination of near-literbike power with near-600 handling.
So what if one of the Japanese manufacturers decided to play up the MotoGP connection by producing an 800cc machine, probably an inline-four, with all the power most riders can possibly use while carrying a pureposefully super-light rotating assembly, which offered a resistance to turning roughly equal to that of a current 600cc sportbike? Better yet, what if the designers conceded that an 800cc machine using current top-of-the-line sportbike technology made all the peak power that is necessary, and re-directed their R&D efforts toward increasing and broadening midrange power and torque without losing the existing top-end horsepower?
The result could be the ultimate sportbike. Imagine an 800 with the agility and razor-sharp reflexes of Yamaha’s R6, combined with near-literbike levels of performance, but delivered in a slightly smoother and softer manner that only cut out the ‘little bit extra’ that, unless you have pro-level riding skills, is only useful for lighting up the tire and putting you on your butt!
Can anybody take the plunge and break out of the currently accepted 600cc/1000cc categories to create this MotoGP-inspired sportbike of the future? We’re not sure, but we hope somebody does!
