From inside (document excerpt):
10 MOTOCROSS OFF-ROAD DUAL-PURPOSE 10 In the world of professional motocross, you can never totally relax. Even soaring 60 feet in the air, you’re looking ahead to the next obstacle– and the one after that. So although we’ve snared the AMA Supercross Championship two years in a row, the YZ testing crew kept looking ahead– designing, engineering, pushing and prodding to make a bike that does precisely what you want it to, precisely when you want it to. The result? Not only have we succeeded; we’re about to shake up the way you think about motocross technology .once again.
Brochure Free Download. Operator’s Motorcycle Cataolg Guide. Free Motorcycle and Catalogue Download PDF. Years covered by this manual: 2010.
WHAT DO YOU DO WHEN THERE’S NOTHING LEFT TO PROVE? IMPROVE. LET THE REVOLUTION BEGIN. A BILATERAL BEAM FRAME MOTOCROSS The culmination of decades of motocross experience, this amazing structure is comprised of 16 pieces of aluminum, either forged, cast, hydroformed or extruded. B REARWARD SLANTED ENGINE A B C Bringing the bike’s mass closer to its center means less resistance to direction changes, providing an ultra-light feel, and making room for a revolutionary intake/exhaust system. C LONG-TRAVEL REAR SUSPENSION A redesigned KYB shock out back carries more fluid in a larger reservoir, and uses a bigger piston for greater consistency through 12.4 full inches of plush travel. D THE BALANCE OF POWER HAS SHIFTED Moving the airbox to the front of the engine let the engineers move the fuel tank lower and rearward; the reward is even greater mass concentration for increased flickability and an ultra-light feel. E FOUR-VALVE HEAD Four titanium valves, fuel injection, higher compression, a shorter stroke and 12mm crank offset are just a few reasons why this YZ450F not only has the perfect power delivery for motocross, but is the most powerful YZ ever. F D E F MORE BUMP ABSORPTION Ten millimeters more stroke and increased fluid capacity in the KYB fork, along with new clamps and geometry, provide the next level of bump absorption, tracking and front-end feel. INDUSTRY CHANGING INNOVATIONS 1972 DT-2X with “Torque Induction, ” or reed valve induction–goes on to be used on every two-stroke motocrosser. 1975 YZ250 with “Monocross ” rear suspension lays down the basic framework of the modern motocross machine. 1981 YZ125–first liquid-cooled Yamaha motocrosser keeps its engine cool with an aluminum radiator mounted to its top triple clamp. 1982 YZ125 debuts Yamaha’s first linkage-type rear suspension and Yamaha Power Valve System for a much broader two-stroke powerband. 1987 YZM500, world’s first aluminum frame factory motocrosser, debuts in the World GP. Data gathered from racing leads to further frame technology. 1998 YZ400F–world’s first production 4-stroke motocrosser becomes the first 4-stroke ever to win the AMA 250 title, under Doug Henry. Meanwhile, Jeremy McGrath wins the Supercross title on YZ250. 2001 YZ250F–The world’s first 250 4-stroke wins the 125cc West SX title right out of the gate under Ernesto Fonseca, then the 125 East title in its second season. 2003 Increasing the five-titaniumvalve single’s stroke to 63.4mm gives birth to the first YZ450F. 2005 Constant development, including an aluminum frame for the YZ250 and YZ125 in 2005, followed by aluminum frames for the YZ250F and YZ450F in 2006. 2009 YZ450F wins its second AMA SX Championship running, this time under James Stewart. 10 Every new bike makes some people stare. The revolutionary new YZ450F will make an entire industry’s jaws drop. As the first production bike built not just with but around fuel injection, it moves the intake system to the front of the engine, while slanting the cylinder rearward– for the most compacted center of mass ever in a four-stroke. The result is instant throttle response, unprecedented balance and uncanny handling.
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