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Editor's Note-- Whether you're a racer, canyon killer, commuter, or sport tourer, the CBR600F3 could be the perfect bike for you--not only is the F3 faster, smoother and better suspended than previous versions, it has captured that elusive quality that Japanese motorcycles lacked in recent decades: Personality.
So what gives the new F3 its new-found personality?
Look no further than the new ram-air airbox -- not something you can see or hear in action -- but its there, nonetheless. And it gives you serious bragging and performance value -- the top-speed gain from this new airbox is phenomenal.
At Honda's semi-secret proving grounds in California's Mojave desert, we ran the new 1995 CBR600F3 side-by-side against its older sibling, the F2. Although there was no radar gun available, the new F3 is at least 5.0 mph faster than last year's model, and probably closer to seven or eight: our 1995 test bike indicated 175 mph around Honda's 7.5 mile flat oval test track while the 1994 model, decidedly slower, could only muster an indicated 167 or so. In the real world, this means that the F3 could be pushing 160 mph.
"We'd guess that the new CBR600 makes seven or eight percent more top-end power."
Seven miles per hour extra doesn't sound like much of a gain until you consider the amount of power needed to accomplish that -- basically, wind resistance is a function of the bike's frontal area times its coefficient of drag times the square of velocity, meaning that exponentially more amounts of power are needed for each mile per hour gain in speed. After doing the math, we'd guess that the new CBR600 makes seven or eight percent more top-end power, a figure difficult to verify on a dyno since its hard to get a 160 mph wind going in the dyno room!
In roll-on tests, the new F3 consistently chugged away from the F2, regardless of what gear we used or the speed we started at. However, in the real world, the deciding factor in winning roll-ons is weight: in our impromptu sessions, the lightest testers always left the heavier ones in the dust, regardless of what they were riding. Eventually, though, the CBR600F3s would always catch and pass the F2s, no matter who was riding what.
The bad news about the new F3, if there is any, is that it tips the scales at a claimed 407.9 pounds, without fluids. Comparatively, last year's F2 weight 2.2 pounds less -- never a good thing to gain weight as the years go by. The heavier bike was a surprise, since Honda went to great lengths to trim weight from the new machine: The headlight is now made of plastic and weighs 35 percent less than last year's, while the swingarm pivot has a larger diameter but is now hollow (generally, larger-diameter hollow tubes are more rigid than solid ones, and can be made lighter) to increase rigidity and save weight.
"The new F3 performed flawlessly, absorbing walloping hits and allowing us to rid over mounds in the middle of an apex at speed, with confidence."
Conversely, metal has been added to the rear wheel, widening it by a half inch, to 5.0 inches. A new, CBR600F3-specific Bridgestone Battlax rear tire is mounted on the rear of the CBR600F3, and, according to Bridgestone, offers the best compromise between sporting grip and life span. Out on Honda's slick road course, the Battlax's performed well, showing minimal signs of wear after a day's testing, though traction wasn't as good as some racing-oriented compounds.
Inside the engine, the CBR600F3's engineers shortened the intake tracts and bumped compression from 11.6:1 up to 12:1 through a more compact combustion chamber and revised piston design. Further aiding power production throughout the rev range are new, low-friction piston rings that supposedly exert 10 percent less pressure on the cylinder wall.The new pistons and rings are mated to lighter connecting rods, which, in turn, are secured to a new, five-main-bearing crankshaft via narrower crank pins--all in the interests of quicker acceleration.
Honda also ditched the old cam chain tensioner that had to be primed with oil on reassembly. Failure to do so led to improper cam-chain tension, meaning the valve timing would be off and the pistons could smash into them.
The engine, fed through new, larger, 36mm Keihin semi-downdraft carburetors (downdrafts are good for performance since the fuel will fall down to the motor of its own weight, and therefor, the manifold diameter can be larger) mates to a new exhaust system that features cross-connecting tubes on the pipe's headers, a la Yoshimura race pipes. This, says Honda, boosts midrange performance.
"Out on the racetrack, the Honda's suspension worked flawlessly right out of the box: We never had to futz with any of the suspension's knobs, dials or other adjustments."
A new fairing on this year's model, slightly narrower and shorter, promises improved airflow to the engine and a lower coefficient of drag, comes in two color schemes: white, yellow & purple and white, purple & red. The fairing, in conjunction with a redesigned front fender, route more air to a new, curved radiatator which, due to its narrower width, reduces the overall width of the motorcycle. Even better, the new F3 runs five degrees cooler, due in part to increased flow to the radiator and because Honda increased the gear ratio in the water pump so it spins faster. In practice, the new system works: While drafting another journalist for three laps around the high-speed oval, our test bike never overheated despite sitting in a pool of buffeting, stagnant air behind the lead F3. Incidentally, while trailing the other rider at top speed, we felt no appreciable power loss -- and when pulling out of the draft, there was no power surge either.
And while its nice to pick up such a massive top speed gain between years -- especially if you race -- we felt an equally important improvement was the F3's suspension. Over the Honda Proving Center's speed bump-like surface, the new F3 performed flawlessly, absorbing walloping hits and allowing us to rid over mounds in the middle of an apex at speed, with confidence. In comparison, the F2's front end was unstable, prone to tankslapping across big bumps -- that you were better off going around--while the rear seemed overly harsh.
But there were no major revisions to the Honda's suspension. Indeed, they use the same rear shock as last year. Instead, Honda improved handling with a series of updates and improvements. First, the triple clamp was strengthened, adding stability. In conjunction with a new fork, which features spring preload adjustments and a new-for-1994 12-click rebound adjust, that improves rebound damping by submerging the rebound damping circuits in oil at the bottom of the fork (they used to be near the top), Honda has virtually eliminated the scary wobble that some bumps could set earlier models into. At the rear, a new, less-linear rising-rate linkage hooks to the unchanged shock, which offers rebound damping adjusters in addition to a spring preload collar.
In truth, we would have preferred a more RR-type update with upside- down forks and maybe 15 pounds less pork to lug around. But we certainly wouldn't prefer to pay more than the manufacturer's suggested retail price of $7,299 (that's in US dollars). That's a $900 price increase in one year! But the good news for value shoppers -- which, as the dollar continues to drop against the yen, is just about all of us -- is that the new 1995 CBR600F3 will give us the best of both worlds: Race-winning speed and technology coupled with good ergonomics, a friendly riding position, and Honda's rock-solid reliability.
Specifications:
Manufacturer: Honda
Model: CBR600F3
Price: $7299
Engine: dohc, 16-valve, inline-Four
Bore x stroke: 65.0 x 45.2mm
Displacement: 599cc
Carburetion: (4) 36 mm Keihin
Transmission: 6-speed
Wheelbase: 55.3 in.
Seat height: 31.9 in.
Fuel capacity: 4.5 gal.
Claimed dry weight: 405.6 lbs.
Time to distance:
60ft 1.735 seconds
1/4 mile 11.317 @ 119 mph
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