Church of MO: 2003 Honda CBR 600 RR – Half One: On Paper

Hmmmm, I don’t bear in mind why we didn’t attend the 2003 Honda CBR600RR press launch 20 years in the past, however I believe it had one thing to do with expensive Minime’s authorized issues on the time, the precise nature of which I additionally disremember. What’s vital is that that 2003 bike marked the unconventional departure of Honda right into a two-R maker of sportbikes in an period when 600s – and all sportbikes – have been high sellers, and it was good. Issues change.

As a result of circumstances past MO management, ahem, we didn’t journey the brand new Honda CBR600RR finally week’s U.S. press launch, however we do have the inside track on what Honda says is “essentially the most superior sport bike Honda has ever produced.”

No huge, actually: Like we mentioned after younger Sean’s rain-out on the Kawasaki ZX-6R/ RR (see additionally the current follow-up ZX-6R monitor check), we don’t actually need to journey this new RR to comprehend it’s going to be a much more succesful bike than almost everyone who buys one. The query as to which of this newest herd of trick 600’s — Yamaha R6, Kawasaki 636R or Honda CBR600RR–is the true efficiency king is just too near name till an actual same-day comparability can come collectively.

Had we ridden the new CBR600RR, it would've looked something like this...

Had we ridden the brand new CBR600RR, it might’ve appeared one thing like this…

And even at that, I really feel secure in predicting that the winner shall be by a nostril (and extremely subjective). Press studies we’ve got learn elsewhere, and dependable sources inside the U.S. motopress, lead us to consider the brand new CBR is, as suspected, fault-free and very competent. Shock. I’m not being flip after I say if you would like a brand new 600 in ’03, going for the one you just like the seems to be of, from a supplier you prefer to take care of, wouldn’t be a foul technique.

On to the CBR-RR then. It’s all-new. As you realize, Honda’s technique with the long-running CBR600 has all the time been “big-circle” philosospy–one bike in a position to do all of it, from every day driver to Daytona racer. With the RR, that philosophy is historical past. The superzoot racey RR shall be offered alongside the pre-existing CBR600F4i–now relegated to sensible-shoes standing. On paper, the 2 bikes don’t look dissimilar in any respect: specs say every weighs 370 kilos dry, 54.7-inch wheelbase for the RR vs. 54.5 for the F4, 24-degree rake for each and almost an identical path figures (95 for RR, 96 for F4). Each bikes even have 67 x 42.5mm, 599cc engines with 12:1 compression.

Note the resemblance, Honda wishes to point out repeatedly, between the RC211V...

Word the resemblance, Honda needs to level out repeatedly, between the RC211V…

The distinction lies within the packaging: within the RR, the rider and engine have been moved ahead, transmission shafts have been stacked a’la Yamaha, and the swingarm’s been lengthened additionally a’la Yamaha–all of which produces a motorbike that may banzai deeper into corners because of superior front-end traction and really feel. Honda’s beating the mass-centralization gong once more. The transmission mainshaft now lies 48.4mm above the centerline of the engine circumstances, which allowed the countershaft to maneuver nearer to the crankshaft. Rotating exhaust ports 30 levels downward (in comparison with the F4i) moved the headers rearward sufficient to shove the compacted four-cylinder even additional ahead. The gas tank, or most of it anyway, sits the place the F4’s rear shock was.

...and CBR600RR

…and CBR600RR

These issues allowed Honda to push the rider totally 70mm additional ahead. Once more, identical to Yamaha and its new R6, Honda constructed the RR’s all-new body utilizing an all-new aluminum casting method: “Hole Wonderful Die-Forged” just isn’t a rapper, it’s the best way Honda now strains sand molds with ceramic, which makes potential finer castings with wall thicknesses as skinny as 2.5mm. (Yamaha’s new method includes utilizing vacuum to suck molten alloy into its molds.)

Utilizing this system within the steering head, predominant spars and swingarm pivot plates, Honda says, provides its engineers better latitude in tuning body rigidity for “enhanced dealing with.”

In comparison with the F4i, the RR has better torsional stiffness within the steering head, decreased lateral stiffness because of thinner rear body rails and vertical stiffness “uncompromised by a beefy construction for the highest shock mount.” All of that, taken from the RC211V, is alleged to end in much less wheelspin at nook exits.

Mr. Swingarm is all trick too, and managed, like on the RC211V GP Honda, by Honda’s new “Unit Professional-Hyperlink” linkage system, which form of compresses the shock from the underside as an alternative of the highest, subsequently inflicting compression of the shock to tug on the bottom body crossmember as an alternative of pushing on the center of the body in typical style. It sounds cool and appears cool; largely it makes room for the RR’s 4.8-gallon gas load to be moved into the significantly better location the shock used to occupy.

The highest half of the gas tank now resides beneath a plastic cowl; forward of it below the duvet sits a brand new, greater airbox. And talking of swingarms, stacking the transmission shafts, and many others., allowed the swingarm pivot to maneuver 30mm nearer to the crank, which in flip made room for the swingarm to be 43mm longer than the F4i’s unit–which produces quite a few advantages: higher mass centralization once more, ahead weight bias, and decreased swingarm angle adjustments because the rear wheel strokes upward.

“Honda says the standard injectors’ proximity to the consumption valve provides prompt throttle response.”

Shorter and narrower, Honda says the new RR engine allows three more degrees of lean to either side.

Shorter and narrower, Honda says the brand new RR engine permits three extra levels of lean to both aspect.

The engine shrunk laterally too. The starter migrated from the left to the appropriate aspect of the crankshaft, permitting the generator to maneuver 21.5mm inboard. Together with reshaped generator and clutch covers and your undertail exhaust, the RR’s obtained three levels extra lean angle in each instructions sayeth Honda. The engine, as we mentioned, is all new too, and Honda says it checked out a bunch of different bore/stroke ratios earlier than concluding that the preexisting one is right.

Peak energy comes now at 12,500 as an alternative of 12,000 rpm–with newfound overrev potential (watch the Yam R6 Mamola vids to grasp the beneficiality of that spherical a racetrack) all the best way out to fifteen,000 rpm. RR pistons are subsequently 131 grams every as an alternative of 145 g (F4i). Smaller piston-pins are 36 as an alternative of 44 g every. New nutless carburized rods weigh 232 as an alternative of 244 grams apiece. Add it up and also you’re taking a look at 4.8 ounces much less reciprocating weight, in an engine Honda says is 0.7 kg lighter than the F4i’s. Consumption valves are actually one mm greater, at 27.5, all of the valves are closed by twin springs, and a brand new, “dual-pivot” camchain tensioner retains out the dread whip, when making use of the whip in high cog.

That's right, 15,000 rpm (tho max power is at 12,500). F4i peak is 12,000 rpm with 14,2 ceiling.

That’s proper, 15,000 rpm (tho max energy is at 12,500). F4i peak is 12,000 rpm with 14,2 ceiling.

Gasoline supply is one other merchandise Honda says got here instantly from the RC211 GP mission: DSFI means Twin Stage Gasoline Injection. 4 40mm Denso throttle our bodies comprise one twelve-hole injector every, which masticate gas and air  beneath 5500 rpm. 4 extra twelve-holers are situated within the roof of the brand new, 15-liter airbox, shower-style, and start spritzing above 5500 rpm about one-billionth of a second forward of the decrease nozzles, all of it completely timed by a brand new, 32-bit ECU. Honda says the standard injectors’ proximity to the consumption valve provides prompt throttle response–whereas the bathe shnozzles’ distance provides time for much more full atomization, in addition to a cooling impact that ends in a denser cost, 125 occasions per second at 15,000 rpm.

And this: “A Twin-Stage Air Induction ram-air system feeds dense, cool air to the airbox, however now through bigger internal/outer ducts. In depth testing within the wind tunnel and on the race monitor confirmed the bigger ducts resulted in a slight improve in steering effort. To counteract that trait, the outer ducts have holes punched by means of them, an thought Honda efficiently tried years earlier than on its Grand Prix roadracers. Because of this, the RR makes high-speed transitions with ease and confidence.” That’s all we’ve got for now. Subsequent step, full-blown comparo?