Cycle News is a weekly magazine that covers all aspects of motorcycling including Supercross, Motocross and MotoGP as well as new motorcycles
Issue link: https://magazine.cyclenews.com/i/128145
2002 Honda RC51 Tech: Winaed Weiaht Watchers In describing the changes made to enhance its performance, Honda officials claim that the 2002 production RCSI is now to the same standards that the 2001 HRC-kitted version of the bike was, and that the performance of the 2002 HRC kit and 2002 works bike have been raised correspondingly across the board. For 2002, Honda engineers placed major emphasis on weight reduction, mass centralization and chassis tuning to improve the breed. Even so, the RC is still described as "very friendly." While the chassis has not lost any rigidity, Honda has taken a different avenue to achieve it in 2002, claiming that it provides a more linear feel than the previous version. Identical to that of the '01 kit bike, the chassis has gained by losing - weight, that is. Mak· ing the switch to stamped engine hangers, more pinch-style engine fasteners and a new steering damper boss has shaved 260 grams off the main spars, this despite the addition of a new, forged-aluminum steering head. A newly designed, HRC-derived subframe is some SS3 grams lighter than the previous version and provides a lower center of gravity for more mass centralization. Honda has also reconfigured the bike's weight bias to place a bit less weight on the front wheel. The front/rear weight bias now stands at SO.7 percent/49.3 percent, differing from the 2001's weight bias of S1.S percent/48.S percent. At first glance the stamped-aluminum swingarm looks boxier and beefier than the '01 version, yet it is some 890 grams lighter. It is also 16mm longer and features a larger opening for better fitment of a racing exhaust system. The pivot shaft is also down 210 grams from that of the '01. Honda found more weight savings by ditching the RC's six-spoke wheels for five-spokers, shaving 900 grams off the rear wheel/tire, albeit with the assistance of the new Dunlop D208 hoop, which features a Kevlar belt instead of steel. Up front, another 43S grams were netted on the wheel and brake assemblies, although the front axle is some 230 grams heavier. So are the brake rotors, which were thickened to Smm, up from 4.5mm, for greater rigidity and heat dissipation. The piston diameters of the four-piston calipers have been reduced 1.Smm, to ] 7.5mm The RCSl's new Showa shock is absent about] IS grams and features a repositioned shock reservoir for compactness and easier adjustability. The '02's reservoir cuts directly behind the shock body rather than sticking out away from it into the open space between the wheel and the shock body. Further revisions were made to the shock linkage ratio, which is 4-percent softer on the bottom and S percent on top. The ratio's flatter curve allows for a 9-percent reduction in compression damping and an II-percent reduction in rebound damping with no spring-rate change. The 43mm Showa HMAS forks underwent a similar evolution, losing 14S grams, 9 percent of compression damping and ] 1 percent of rebound damping with no spring· rate change. The RCS] 's engine was not left alone, either. Honda engineers elected to fit the 999cc V-twin with HRC·spec injectors, exhaust ports and exhaust system. The '02 throttie bodies are actually the same as those found on last year's RCS] World Superbike, measuring 62mm . up from 54mm. They also feature 12 spray nozzles where there were previously just four, increasing fuel flow by 8 percent. The exhaust system is some ]060 grams lighter than last year's, mostly due to thinner wall mufflers. The RC's ignition timing has also been bumped up two degrees to 37 degrees BTDC for increased low to midrange power. Cooling has also been revised. A pair of smaller cooling fans replace the '01's larger single unit to direct air to the radiators. The RC's oil cooler has also been moved from horizontal to vertical. Finally, Honda has attempted to make the RCSI even more user-friendly via a larger storage compartment in the tail section and a 30mm-taller windscreen - though even the screen adjustment is derived from Colin Edwards II's Castrol Honda RCS]. Adding up all the changes results in a RCSI that is ]] pounds lighter with two more horsepower than the previous version. So maybe now it's perfect? 20BGP supersport tires for the afternoon sessions made a huge difference in the way that the ReS1 handles. That's something that you quickly learn when jumping back and forth between the two types of tires anyway: While the only sensible choice for bikes ridden back and forth to work - and those flogged hard in the canyons on the weekend' - OE tires cannot hold a candle to the (Below) Too bick? The LCD tachometer is the last word in high tech, but it Is hard to read at speed. The speedometer, on the other hand, Is easy to spot. (Above) The twin 320mm Hissin front binders offer excellent feel, but we'd like to get a little more clamping force out of the four-piston calipers. 26 MARCH 13, 2002' II: U II: I e n e _ :IS Specifications ~tUUl4 ie{?5_'=------_ ENGINE .................••.••..............999cc liquid-cooled 90- V-twin BORE x STROKE '.' ] OOmm x 63.6mm COMPRESSION RATIO ]0.8:1 VALVETRAIN DOHC; four valves per cylinder CARBQRETJON PGM-FJ with two injectors per cylinder IGNl1l0N Computer-controlled di9ital with three-dimensional mapping TRANSMISSION Close-ratio 6-speed FINAL DRIVE IIS30 O-ring-sealed chain SQSPENSION Front .43mm inverted HMAS cartridge fork with spring preload. rebound and compression damping adjustability; S.] inches travel Rear HMAS Pro-Unk single shock with spring preload, rebound and compression damping adjustability; 4.7 inches travel BRAKES Front Dual fuJl-fioatin9 320mm discs with four-piston calipers Rear ...........•.... , Single 220mm disc with single-piston caliper TIRES Front J20/70ZR- J7 Dunlop radial Rear ] 90/S0R- 17 Dunlop radial WHEELBASE ...• , ••••.......•...............................SS.9 inches RAKE/TRAIL .............•..•.•.•..•....•.•.••..•...•..23.So/94.6mm SEAT HEIGHT .•.......•....•... , ..•.... , .. , ..•.•.....•.•.32.3 inches CLAIMED DRY WEIGHT ••..•.•....•........••..•...•.•••.••. .430 pounds FQEL CAPACITY •••.••..••••••.•....•.4.8 gallons, including 1.2-gallon reserve COLOR .....•.••.•••.....•.........................Red/Metallic Silver MSRP ....•...•...•••.••..•....•.••........................$10,199