2005 Honda CBR 600RR

Subtle changes make the difference

Waiting for Buttonwillow Raceway's 1.9-mile West Loop to dry under a thick layer of Central Valley fog, it's easy to mistake this 2005-spec CBR600RR for the '04 model parked alongside it. Walking around the new bike with a fresh cup of coffee, differences are subtle. The '05 bike's new plastic skin is a little sleeker, tailored to cheat the wind and reinforce its resemblance to the CBR1000RR as well as Honda's RC211V MotoGP weapon. Up front, the inverted 41mm fork, radial-mount four-pot Tokico calipers and 310mm rotors are de rigueur for any hardcore '05 600-classer.

The most significant changes, however, are harder to see.

Two years ago, Honda's first RR-spec 600 was maligned for a 445-pound wet weight--30 pounds heavier than an equivalent Yamaha YZF-R6. For Hitoshi Akaoka, large project leader for the '05 CBR600RR, saving weight was a priority from the beginning, but it had to be lighter in all the right places. "One of our main goals," Akaoka says, "was to improve feel through transitions." A simpler, lighter muffler and rear subframe help on both counts, saving weight high in the chassis where you notice it most. Akaoka found extra ounces everywhere. Thinner walls in the main spars and elsewhere took 3.6 pounds out of the '05 frame without compromising rigidity. The Unit Pro-Link swingarm's upper shock mount is cast in rather than bolted on, saving a few ounces and making the mechanic's life easier in the bargain. The shock itself is shorter and lighter, with an aluminum adjuster replacing last year's steel bit. A gull-wing-style top triple clamp allows shorter, lighter fork tubes. The front axle is shorter and lighter. So are the footpeg and handlebar mounts.

Strategic intake and exhaust tweaks aim at a more usable power curve: fatter in the middle without giving anything away on top. Honda's Dual Stage Fuel Injection feeds each cylinder with a pair of new injectors--one in the roof of the airbox and another in each intake port--to deliver more fuel in less time. New intake ports accelerate fuel and air through a narrowed venturi section, filling the CBR's cylinders more quickly than before. Revamped to match changes on the intake side, the lighter 4-into-2-into-1 exhaust system helps them empty in a hurry as well.

Since we couldn't drag our Superflow CycleDyn rear-wheel dyno up to Buttonwillow for the festivities, we can't tell you how the '05 engine stacks up versus its predecessor. We did bring our Intercomp SWII scales along, though. Complete with the same 4.8 gallons of fuel as last year's bike, the '05 version weighs in at 430 pounds--11 pounds lighter than our '03 test bike. That's a significant difference on paper. It's a bigger difference out on the track.

Ergonomics are essentially unchanged. The CBR is a better fit if you're 5-foot-8 rather than 6-foot-3. Aside from a predictable shortage of legroom, this latest version is a surprisingly humane track tool. Midrange is a relative term to an engine that revs to 15,300 rpm, but there's more of it here. Serious power kicks in just beyond 8000, building in a potent rush to nearly 14,000 revs with no obvious peaks or valleys in between. High revs and small cylinder volume make high-revving 600s the biggest challenge for Honda's fuel-injection engineers, but you'd never know it from riding this one. With the tach needle between 7000 and 14,000 rpm, Honda's new EFI sends a virtually seamless flow of power through the smooth-shifting six-speed. Credit some of that to a separate ignition map for each gear.

Looking for damp stretches between the puddles, CBR steering is dead-neutral, with the usual mix of quickness and stability. Honda's testing crew had 3mm more fork tube showing above the top triple clamp than stock, so our bike turned a little quicker than it would have right out of the box. Despite the lack of a steering damper--Akaoka-san told us a 1000RR-style electronic HESD unit was unnecessary--the CBR600RR never felt even vaguely nervous. You notice the 13 missing pounds a little bit everywhere. After threading Button-willow's stinky-fast esses a few times, you want to buy Akaoka-san an ice-cold Asahi. Quick transitions take far less muscle on the new bike. We never complained about its predecessor's brakes, but this year's CBR1000-spec calipers are astonishing: powerful enough to scrub off triple-digit speeds with a calm two-finger squeeze and not a trace of fade.

But how did Akaoka and company add all that to the new RR's repertoire while adding only $200 to last year's $8599 bottom line? They save money elsewhere. The rear fender stay that was four pieces of aluminum and plastic in '03 is now two pieces of fiber-reinforced plastic for '05. The four bolts that held the top shock-mount are four less parts to pay for and put together. The list goes on far longer than we can. Akaoka-san could have come up with the best 600 in the world, but if it came with a $10,000 price tag, Honda wouldn't build it because you wouldn't buy it.

The best sporting 600, more so perhaps than any other niche in sportbike land, has to have it all. Big power, light weight, sharp handling that doesn't bite, reasonable comfort, good looks and a nice price. While it's way too early to come anywhere near that kind of call, if one day at the track is any indication, Honda's latest has enough of everything to run up front.

Honda CBR600RR
MSRP $8799
Type l-c inline-four
Valve arrangement dohc, 16v
Displacement 599cc
Transmission 6-speed
Weight 430 lb. (wet)
Fuel capacity 4.8 gal. (18.2L)
Wheelbase 54.5 in. (1384mm)
Seat height 32.3 in. (820mm)
Among obvious differences in the '05 bodywork are less conspicuous ram-air intakes under the headlights.
a small bike for big people, but the CBR is your friend at speed.
Terry Newby of Sport Tire Services levers one of Dunlop's ultra-sticky D208 GP-JLB radials onto an RR rim at Buttonwillow.