So what does it take to be a PURE PERFORMANCE machine?

Quickest Acceleration So how does Yamaha build the quickest accelerating ATV on the market? How about starting will a lot of parts from the most impressive YZ450. Take the five lightweight Titanium valves, the all aluminum ceramic coated cylinder, the dual overhead cams with the same intake cam as the YZ450, the direct ignition, the lightweight magnesium valve cover, and the magnesium quick access clutch cover. Throw in the exhaust camshaft from the WR450F with auto decompression lever and decompression cam pin. Add a newly designed piston with minimal piston skirt and a larger piston ping diameter than the YZ450F. Set the compression at 11.9:1 and require Premium unleaded fuel. Use a Keihin FCR carburetor with Throttle Position Sensor. Make it ATVA legal at 439cc and use a close ratio 5 speed transmission to put the power to the ground. Best Handling In the past, most showroom ATV's have NOT had a true performance suspension and one of the first upgrades required has been in the shock department. The new YFZ450 intends to change that. In the front Yamaha has installed piggyback aluminum Kayaba shocks that are completely adjustable, revalveable, and rebuildable. These shocks have compression adjustment, rebound adjustment, and preload adjustment. They are Nitrogen filled for fade resistance and quick response. To complete the front suspension the A-arm has been designed for long travel and a low center of gravity. Lightweight components are used with a forged aluminum knuckle and A-arm end and a lightweight aluminum upper A-arm. In the rear, the suspension has been designed for tuneability and low unsprung weight.Yamaha has done this by including technology from the YZ. The linkage and layout, with centralized mass, is all YZ style. To compliment this a very trick new forged swingarm is included. The swing arm is very light and has an anitsquat design. The shock is a Nitrogen filled Showa unit with piggy back aluminum reservoir. The shock is preload adjustable, compression adjustable adjustable, AND rebound adjustable. Last but not least is a new chain adjuster that looks to be much easier to use than the units on other Yamaha models. In the brake department Yamaha has borrowed even more YZ technology with the YZ dual piston hydraulic disc brakes in the front and the same brake pad material as the YZ. They have designed the front braking system to give you the same responsive feel and stopping power that the YZ has. Even the tires are all new. The front ones are of a modified Raptor design with a stiffer sidewall. The rears are an all new design optimized for cornering and acceleration. The levers bring more YZ technology with completely adjustable clutch and brake levers just like the YZ450F. The parking brake is a completely new toggle lever design. Of most importance to the racers is that it eliminates that contact switch that usually exists and is removable without putting a complete new clutch perch assembly on the quad. The seat is low and flat for good mobility. The seat height is only 31.5 inches, nearly 1/2" lower than the Z400. The footrests also come from the YZ450F and are a full 45mm wide. Lightest Weight Only 350 pounds. That is 22 pounds lighter than the Z400 and 65 pounds lighter than the Polaris Predator. Yamaha has achieved this by paying attention to the details. Cast aluminum hubs, swingarm, and rear subframe. Aluminum upper A-arms and wheels. Aluminum, titanium, and magnesium in the engine. And a high tensile strength steel frame. Want to make it even lighter? Install a GYT-R kick starter and get rid of the electric starter and battery. This will shave another 15 pounds or so off the YFZ450. What about hot start problems? Just add a YZ hot startbutton. How about Accessories?

Right from day one you will be able to get key GYT-R accessories direct from your dealer. We already mentioned the kick start kit. You will also be able to add a performance exhaust system, billet shifter and billet brake pedal, aluminum A-arm and engine/frame skids, and a custom aluminum front grab bar. For some additional width you can get +1 A-arms and adjustable rear axle and still keep it under the ATVA limit of 50".

Specifications

2004 Yamaha YFZ450

The new 2004 Yamaha YFZ450 may be the spark to REALLY light off ATV racing. We are talking a pure performance machine that can be purchased right off the showroom floor for $6,899. Sure, there are performance machines available now but the typical enthusiast must spend many additional $ if they want to head out to the race track and have a competitive machine. The YFZ450 stands to bring that entry point down much lower than it is today. The 2004 YFZ450 could have one of the most significant impacts on the Sport ATV market since Honda introduced the 400EX in 1999. Get your order in and look for the new YFZ450 to start arriving in dealerships in the next couple months. Next month we will have our first ride report. Photo Gallery - Lots of cutouts and closeups of the new YFZ450 and GYT-R accessories   • Contact Information Yamaha Motor Corporation USA www.yamaha-motor.com