Honda Cbr600f4i
Honda CBR600F4i
Sharper, yes, but is it less friendly?
BRIAN CATTERSON
NOBODY DOESN'T LIKE HONDA'S CBR600. EVER SINCE THE ORIGINAL HURRICANE blew onto on the scene in 1987, the CBR has been praised for its just-right combination of sporting prowess and general streetability. It has traditionally been a bike on which beginners feel right at home, experienced sport riders find easy to ride fast, and racers can put in the winner’s circle. Honda deserves a lot of credit for that. For 2001, the CBR600F4 has received a makeover and gained an important letter at the end of its name, “i” as in “injected.” Like Suzuki did this year with its GSX-R600, Honda decided it was high time fuel-injection trickled down to the 600cc class, and so the CBR600F4i wears throttle bodies instead of carburetors. Of course, there’s also the obligatory raft of sensors to monitor the various engine functions, providing the ECU with the information it needs to mix fuel, air and spark in the appropriate proportions. But one thing you won’t find is a choke lever, I thanks to the built-in cold-starting auto-enrichening system. And while there is no way for owners to adjust the EF1 themselves, the available HRC race-kit black box will have a port to which you can connect a laptop computer, and the aftermarket will no doubt step forward with similar devices.
Because the four 38mm throttle bodies are significantly shorter in height than the 36mm carbs they replaced, the engineers were free to increase the size of the airbox or the fuel tank. Or both, which is what they did; the combined volume of the ram-air intake
CYCLE WORLD TEST
ducts and airbox has been increased from 13 to 15 liters, while the fuel tank was upped .3-gallon to 4.8 gallons.
There are a bunch of changes down below the throttle bodies, too, all in the interest of improved high-rpm performance. Each of the eight intake valves now has a pair of nesting springs and sits on a hardened seat, while the cam sprockets are lighter, the camshaft oiling holes are bigger, the piston rings have less friction and the air transfer holes are larger for less internal pressure. The sum total of these changes is a redline that climbed from 13,500 to 14,200 rpm.
The exhaust system is all-new, too, with reshaped header pipes and a muffler that has new internal baffling and is angled more upward for increased cornering clearance.
A new clutch with eight plates (the old one had seven) combined with a revised shift-lever assembly and re-angled gears are meant to improve shifting action. Shorter fifth and sixth gears, plus a one-tooth-larger (46 versus 45) rear-wheel sprocket, help acceleration, yet thanks to the other engine mods, top speed is said to have been unaffected.
Other detail changes include iridium-tipped sparkplugs and a new alternator that produces 20 percent more power while weighing less than the old one, in the interest of quicker throttle response.
California-model F4is will meet CARB 2004 Tier 1 emissions standards, and will differ in that they’ll have an airinjection system and a three-way exhaust catalyzer.
The aluminum frame also received its share of changes, the most noticeable of which is a coat of black paint. More
importantly, lateral rigidity is said to have been increased by 7.4 percent, torsional rigidity by 10.9 percent and overall rigidity by 5.9 percent. New casting ribs behind the steering head and swingarm-pivot plates play a major role in this development, as do beefier engine, swingarm and lower shock mounts.
The aluminum swingarm now pivots on three bearings, one needle on the left and one needle and one ball on the right.
New this year, too, are the front brakes, four-piston Nissin jobs with molybdenum/anodic-oxide-coated pistons and Teflon-coated rollback seals. Both of which are aimed at reduced friction, for consistent, fade-free performance under repeated use.
The brake rotors are new, as well, flatter with less offset for reduced flex, allowed by the wheel bearings being spaced farther apart on the new, CBR929RR-style hollowspoke wheels.
Of course, no makeover would be complete without a new look, and the F4i certainly looks new, borrowing styling cues from the CBR929RR, CBR1100XX and VFR800 (relax, it looks better than it sounds). Starting at the front, with its dual 55-watt H7 headlights, L-shaped air intakes and higher yet more aerodynamic mirrors. As on the RC51, only the F4i’s left headlamp illuminates on the low-beam setting, for that Suzuka 8 Hours look. Toggling to high-beam brings the other lamp into play. Behind the headlights is a new dash, with a digital speedo, analog tach, dual tripmeters and clock. There’s also a shift light that illuminates at redline, plus a trick low-fuel warning system that flashes each of its four LCD bars as the tank nears empty. >
Moving rearward, the seat is now a two-piece affair, with a racer-thin rider’s squab and a separate passenger perch that can be replaced with a solo seat cowl, once such a thing is made available.
To introduce the F4i to the press, American Honda invited us to its home away from home, Las Vegas Motor Speedway, site of the Freddie Spencer High-Performance Riding School. As has become common practice, The Fred and his fellow instructors Jeff Haney and Dale Kieffer led the press in the initial sessions, gradually getting us up to speed. While I appreciated the gesture, I didn’t really need to play follow-the-leader. Not that I know my way around Vegas so intimately (not the racetrack, anyway), it’s just
that CBRóOOs have always been so easy to ride, so welcoming, that you don’t need much time to acclimatize.
One of the benefits of attending a press introduction is that the R&D staff usually arrives a day early, so that they can fine-tune the bikes. And true to form, Honda’s Doug Toland (former World Endurance Champion and CW staffer) and new boy Kurt Risic did just that, determining optimum suspension settings for the stock Michelin Pilot Sports we’d ride on in the morning, as well as the Pilot Races we’d sample in the afternoon. (Some F4is will come on Bridgestones or Dunlops.) So it was little surprise that we didn’t change a clicker all day.
Like all CBRs before it, the F4i wears its handlebars above the top triple-clamp, which combined with low (by sportbike standards) footpegs and the new 5mm-higher seat makes for a roomy riding position. The higher bars also give the rider a bit more leverage, which let Honda endow the F4i with a bit more rake and trail than some of its competitors, for enhanced stability with little penalty in terms of heavier steering. As always, the CBR’s steering is superbly neutral, on the brakes or off. The only bad part about the high bars is that they encourage you to sit up rather than tuck in, which not only made the bike wobble during the abrupt transition onto the Vegas banking, it looks bad in photos, too! Ever wonder why Kurds Roberts hangs so far over the front of his bike? Now you know.
One of the reasons fuel-injection came to the 600cc class so late is because it’s more difficult to make it work on a small, high-revving engine. So kudos to Honda’s engineers for waiting until they got it right. Throttle response is as crisp and smooth as on any carbureted bike, with none of the off-idle herkyjerky that plagued some earlier EFI models. Just for giggles, I rode a whole lap in sixth gear, and the F4i handled it with aplomb; oh, it didn’t exactly rocket off the comers, but it didn’t protest, either.
Two complaints we’ve had about previous CBRs have been vibration and notchy shifting. And while the racetrack is no place to judge vibration (let’s just say it felt comparable to the old bike), shifting action has definitely been improved. A couple of journalists voiced concerns about missed shifts until they realized that it only happened in the two long infield left-handers, where it’s hard to get your foot under the shift lever while you’re leaned over. Heeding the advice of the more experienced riders on hand, they started to short-shift entering those sweepers and had no further problems.
A few testers also complained about brake fade, the lever turning to mush after a succession of hot laps. Honda promptly responded, bleeding the brakes on all the bikes and changing pads. But to be honest, I never had any such problems, and it wasn’t because I was lollygagging, either. As a matter of fact, none of the faster guys had any complaints about the brakes, probably because they weren’t slowing down as much for the comers!
The one concern I did have at the track was lack of cornering clearance. Even with the shock spring set at maximum preload, the footpegs dragged so badly that the feelers were completely worn away by day’s end. But street riders will rarely lean over that far, and serious racers will fit rearsets and a ride heightadjustable shock, so maybe it’s a moot point.
There was, however, one more telling observation made by a couple of testers at Vegas, and it had to do with the 2000model F4s that Honda brought along for comparison. Ordinarily, a manufacturer brings out a couple of old bikes so that we can see just how far the new one has progressed. But in this case, there was some life left in the old girl yet!
Sure, the new, fuel-injected bike revved much quicker above 7500 rpm, ripping toward redline as though you just punched the hyperspace button. And it showed a bit more speed at the end of the front straight, too-just shy of an indicated 160 mph, if you could read the speedo past the unfortunately placed clutch cable. But the old, carbureted model actually seemed to accelerate harder exiting the pair of second-gear left-handers that lead onto the two long infield sweepers-the most important comers on the track if you subscribe to conventional wisdom, because they lead onto the longest straights. And this despite the fact that the old bike is geared taller than the new one.
Some of the Honda folks suggested that the old bike may only have felt stronger because it wasn’t as smooth as the new one, but I don’t think that’s the case. The only conclusion to be drawn is that in striving for greater competitiveness on the racetrack (read: top-end power), Honda had to sacrifice part of what has traditionally made the CBR such a splendid all-around streetbike (namely, midrange).
That suspicion was confirmed a week later in California, when we ran the F4i on our in-house dyno. Sure enough, the new bike did indeed make less midrange power than the old, and surprisingly, it showed no increase in peak power, either.
Performance testing backed up our dyno findings. At Carlsbad Raceway, the wheelie-happy F4i sprinted through the quarter-mile just .06of a second quicker than the old bike, and on a blustery day at our top-secret high-desert testing facility, it went 4 mph slower on top.
So, while the F4i certainly feels faster than the bike it replaces, it offers no measurable performance advantage. The real improvement lies in what the engineers call “racing potential,” meaning that this bike will respond to per-
formance modifications better than the old one did. Which is all well and fine, except that in their quest to build a competitive race platform, the F4i design team may have taken one step forward and two steps back, turning what was one of the great entry-level sportbikes into something less friendly.
All of which is very un-Honda, and particularly very unCBR600. Fortunately for beginners, there are other, mellower options, not the least of which is a used F4.
For everyone else, however, the F4i’s new sharper edge makes it the best CBR600 yet. □
HONDA
CBR600F4i
$8199
EDITORS' NOTES
NOTHING ENHANCES THE SENSATION OF acceleration aboard a motorcycle quite like a progressive power wheelie. There’s no whacking the throttle, dipping the clutch, or tugging on the bars required to get the F4i’s front wheel moving in an upward trajectory, just a whole lotta throttle in low gear!
While wheelstands deliver big-time thrills, pulling a moto-mono doesn’t
exactly yield the quickest quarter-mile time. I can’t recall ever having as much difficulty keeping the front of a stock 600 from coming up during that crucial first 60 feet of a run.
Several passes down Carlsbad Raceway’s strip left me a bit frustrated with a best time of 10.91 seconds. That’s plenty quick for a 600, but I could sense greater potential (another tenth at least) exists in the bike. Here at CW we don’t apply a correction factor to our times, but perhaps there should be some adjustment for the PWF (Prominent Wheelie Factor) when testing at sea level.
-Don Canet, Road Test Editor
I’VE BEEN WAITING FOR THIS MOTORCYcle. Ever since Honda introduced the VFR Interceptor with its superb electronic fuel-injection, an EFI-equipped middleweight seemed just over the horizon. It took a couple of years, during which time throttle bodies also popped up on the CBR1100XX and CBR929RR Open-classers, but the technology migrated downstream nonetheless.
As we’ve come to expect from most any late-model Honda, the F4i’s steering is magically neutral, on or off the brakes. And the redone cosmetics (dig that Suzuka 8 Houresque, low-beam headlight treatment) add an element of raciness that simply wasn’t there before. If you’re a nitpicker, the only thing missing is an in-the-cases swingarm pivot. As for me, though, aside from the speedometerblocking clutch cable, there’s nothing to dislike.
So once again, Honda comes through. And in a big, big way. Take it from me, the wait is over. Only problem, how am I going to get eight large past my wife?
Matthew Miles, Managing Editor
AT THE F4I PRESS INTRODUCTION IN LAS Vegas, Project Leader Hiroyuki Ito was asked why the CBR600 was never spun off into separate street and race versions. His answer was that he subscribed to the same “Big Circle” philosophy expressed by CBR929RR Project Leader Tadao Baba-that one motorcycle can be versatile enough to address all possible uses.
Well, that’s a noble ideal, and it may indeed prove workable for an Open-classer, but it’s much more difficult to achieve with a middleweight. You’ve got to give to get, and in the F4i’s case what they gave up was the CBR’s traditional happy-go-lucky demeanor.
Normally, that wouldn’t bother me, but this is the CBR600 we’re talking about-the floppy-earred labrador retriever of sportbikes. So maybe it’s time American Honda offered two different CBR600s. It’s not such a far-out concept; they’re already doing it in Europe. -Brian Catterson
