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Sep 10, 2002

Fuel-injected 2003 Yamaha YZF-R6 Is Lighter And Features Cast Frame

From a press release issued by Yamaha:<BR><BR>Redesigned 2003 Yamaha YZF-R6 Hits Harder and Handles Better<hr noshade size="1" width="475" align="left"><img src="../issues/sep02/r6_1.jpg"><hr noshade size="1" width="475" align="left">Three More Horsepower, Eight Pounds Lighter, And Fuel Injection Make The R6 a Top Contender For the 600cc Class Crown<hr noshade size="1" width="475" align="left"><img src="../issues/sep02/r6_3.jpg"><hr noshade size="1" width="475" align="left">In 1999 Yamaha brought forth the original R6, a bike containing the world's first 200-horsepower-per-liter production engine packed in a cutting-edge chassis that rewrote the handling handbook. Light, excruciatingly agile, and revvable beyond 15,000 rpm, the R6 would go on to victory in nearly every 600cc media arena it entered--as well as being named 2001 Bike of the Year by Sport Rider magazine. For 2003, the R6 has undergone a wheels-up redesign, with a stronger, cleaner, fuel-injected engine, a revolutionary frame that's the first ever to use Yamaha's exclusive new casting technology--and a stunningly modern look from the point of its exclusive Gatling-beam headlights to the tip of its LED taillight. <BR><BR>Stiffer Is Better: Deltabox Iii<BR>Fantastic handling has always been job one for the R6 crew, and racing teaches that handling begins with frame rigidity. Thanks to a new, more efficient vacuum-assisted aluminum casting technique which produces a purer, stronger piece, the R6's all new Deltabox III has 50 percent greater lateral frame rigidity than before--and approaches that of the R7 Superbike frame. "Controlled filling aluminum die casting" technology (CF) allows the new frame to be made entirely of aluminum castings--a mass-production first--and from far fewer frame components than before. Where the previous frame required 16 welds, the new bike needs only two. Greater casting precision also allows more rigid engine mounting; in place of adjustable forward engine mounts, the new frame uses direct mounts, which further increase chassis stiffness and enhance feedback.<hr noshade size="1" width="450" align="left"><img src="../issues/sep02/r6_2.jpg"><hr noshade size="1" width="450" align="left">Strong Arm Tactics<BR>CF die casting is used again in the new swingarm, making possible a lighter arm that's also stiffer. CF simply allows placement of more material where it's needed, less where it isn't. Sections of the swingarm are as thin as 2.5 millimeters. For greater traction and feel, the new arm is 10mm longer than before, and the offset between the countershaft axis and swingarm pivot axis has been reduced from 96 to 86mm. While wheelbase remains a quick-turning 1380mm, fork offset has been reduced 5mm, to 35mm, for lighter-feeling, more communicative steering.<BR><BR>Functional and stylistic design aspects were considered in unison. That means the new frame looks as radical, and beautiful, as it feels.<hr noshade size="1" width="450" align="left"><img src="../issues/sep02/r6_6.jpg"><hr noshade size="1" width="450" align="left">Goodbye Jets, Hello Fuel Injection<BR>Adaptation of the same critically acclaimed "suction-piston" type fuel injection introduced last season on the R1 gives the new R6 the same feeling of excellent, smooth carburetion--along with the reliability and response of electronic control. Throttle bodies of 38mm diameter replace the 37mm carburetors, and are fed pressurized air through a larger airbox and intake optimized to work with the new injection system.<BR><BR>More Power<BR>Rather than go the traditional route--more peak power via bigger bores and shorter stroke--Yamaha engineers wanted more power but not at the expense of the excellent midrange response and lively feel of its "long-stroke" engine. Instead, they concentrated on improved intake efficiency and reduced pumping and friction losses to extract three more horsepower— 123(with ram-air)--at the same 13,000 rpm as before, with a second power curve beginning at 8000 rpm. Higher-lift cams, with less overlap (made possible by fuel injection) further enhance the R6's strong midrange throttle response. Though engine dimensions, compression ratio and combustion chamber shape are unchanged, 90 percent of the engine parts are new.<BR><BR>Linerless Direct-Plated Cylinder<BR>Again, breakthroughs in die-casting now allow production of an upper crankcase/ cylinder block with greatly reduced oxides in the molecular matrix. This produces a much stronger, more consistent cylinder, to which ceramic composite plating can be directly applied, instead of to a cast-in sleeve as before. Benefits include better heat dissipation and a more exact cylinder shape. Combined with stronger, forged pistons and redesigned rings, the new engine enjoys better gas seal and greater piston stability.<BR>Other engine changes include reshaped transmission gears and journals for improved shifting, an aluminum oil cooler, increased engine cooling capacity, and rare-earth magnets for a lighter flywheel.<BR><BR>Clean<BR>Once fuel is burned, a catalyzer and air induction system in the exhaust let the new R6 pass the stringent EU2 emissions standard by converting CO to CO2, hydrocarbons to CO2 and H2O, and Nox to N2, H2O and CO2. At the same time, the new exhaust system is 2.2 pounds lighter, quieter and more efficient, thanks to titanium internals with greater volume and higher flow.<BR><BR>Looks Ready To Pounce...<BR>R6 designer Takeshi Iimura designed the R6 to give the appearance "of a machine that gobbles up lots of air and turns it into power." Use of a new-technology "Gatling beam" headlight led to the R6's look as well. "This is a case of new technology leading to new design elements... this headlight became the defining element in the front face design. Also, in order to visually express the increased sense of road holding in the front end, we created a side view that gives the impression of the body grasping the front tire...."<hr noshade size="1" width="500" align="left"><img src="../issues/sep02/r6_4.jpg"> <img src="../issues/sep02/r6_5.jpg"><hr noshade size="1" width="500" align="left">CF casting let the design team have a larger say in the appearance of the frame and beautiful swingarm. Even the new five-spoke wheels benefit from new casting techniques which make them lighter, stronger and more aesthetically pleasing. <BR><BR>Decisions<BR>The new 2003 Yamaha YZF-R6 will be available in three colors: Yamaha Racing Blue, Liquid Silver, and black with red flame job ($100 extra). Look for it to hit dealerships in early 2003. MSRP to be announced.<hr noshade size="1" width="450" align="left"><img src="../issues/sep02/r6_7_sm.jpg"><hr noshade size="1" width="450" align="left">