Yamaha's Yzf-R6 Ups the Ante
YAMAHA'S YZF-R6 UPS THE ANTE
JUST ABOUT THE time we settle on which 600cc sportbike is best in a given year, the manufacturers start rolling out next season’s models. Yamaha beat everybody to the punch for 2005 with its heavily revised YZF-R6. The bike retains its distinct, familial look, but underneath that sharp bodywork several changes were levied to counter strides made recently by the competition, most notably Suzuki’s class-conquering GSX-R600.
Topping the bill? More juice from the dohc inlineFour. Yamaha claims a 3horsepower boost at the crank, which should put rear-wheel horses in the 104-105 range. Power comes from increased throttle-body diameter of 40mm, up from 38. Fuel-injection pressure is increased, feeding new injectors for better fuel atomization and greater flow. New velocity stacks are used to help improve midrange power. Two cooling fans instead of one dissipate increased engine heat.
The expected underseat exhaust (a la the unchangedfor-’05 YZF-R1) was not adopted. A 41mm inverted fork, however, was, addressing the Yamaha factory racing team’s biggest complaint about the R6 in Supersport racing: chatter from the old-style (and more flexible) conventional piece fitted in ’04.
The stiffer fork necessitated frame changes. “What the engineers found was that when they changed the fork, they really had to alter the frame more than expected,” said Yamaha Public Relations Manager Brad Banister.
Casting thickness was upped on the rear swingarm pivot plates and shock mounts to increase rigidity. The rear suspension also got a higher-rate spring, with the linkage ratio made more progressive. Chassis geometry is now optimized for the common race-rubber-size 120/70ZR17 front tire, replacing the previous 60series.
The front brake discs are 12mm larger in diameter at 31 Omm, with thickness reduced ,5mm to 4.5. A radial master cylinder and radialmount calipers round out the brake changes. Price is expected to remain around $8000.
“The main goal was to increase racetrack performance,” said Banister. “There are more people than ever doing track days, and we wanted to bring the bike up to snuff.”
No doubt the factory Supersport team is all smiles. Technology accelerates on!
-Mark Hoyer
