| Calendar | ATV/UTV Forums | ATV/UTV Reviews | ATV/UTV News | ATV/UTV Product Reviews | ATV/UTV Racing | ATV/UTV Trails | ATV/UTV Videos

ATV Bone
Machine Reviews
Press Releases
Product Reviews

» Arctic Cat

» ATK/Cannondale

» Can-Am

» E-Ton America

» Honda

» Kasea

» Kawasaki


» Polaris

» Suzuki

» Yamaha

ATV Clubs
Classified Ads


Yamaha Motorsports

YFZ 450

Yamaha's YFZ450Welcome To the New ATV World Order

If you've heard it, you can't forget the awesome sound of the liquid-cooled DOHC five titanium-valved single in the baddest motocrosser ever built - the YZ450F.

We had no choice but to adapt that engine for use in the most serious ATV the planet's ever come up against. We call it the YFZ450, and nobody else builds anything like it.

Not only is the hybrid 439cc DOHC titanium-valved five-speed engine far superior to anything that's come before, at 350 pounds, the YFZ450 is endowed with the highest power-to-weight ratio of any four-stroke ATV ever built.

Yamaha's YFZ450Yes, it even has electric start, and when you open the 39mm Keihin carburetor all the way and take aim, you'll also appreciate the lowest center of gravity in the class and the latest industry-leading suspension technology.

But we’re just getting warmed up here, so why don’t you visit the Features & Benefits page to get a closer look at the YFZ450's list of incredible features.

You'll see, it all adds up to the lightest, most powerful, best-handling ATV ever produced. It's simple. You'll either be riding a YFZ450 this season or trying to catch up to one.

Manufacturer's Sugg. Retail Price...$6,899*

2004 YFZ 450 Features & Benefits


  • Yamaha's YFZ450Liquid-cooled, 439cc, 5-valve, DOHC, 4-stroke with titanium valves features 95mm bore and 62mm stroke delivering, broad torque curve (for instant hook-up) with high over-rev capacity and crisp, linear throttle response.
  • Reliable, push-button electric start in any gear adds extra convenience.
  • High performance 39mm Keihin FCR flat-slide carburetor with throttle position sensor (TPS) delivers ultra-precise fuel/air mixing and instant throttle response.
  • Dry sump engine carries oil in an aluminum tank directly in front of the engine for excellent cooling and optimal protection from rocks or mud.
  • Digital CD ignition system delivers ultra-precise spark and 3D timing for faster, stronger engine response during hard acceleration.
  • Lightweight crankshaft keeps inertial mass to a minimum for faster-revving low-rpm response.
  • Piston features short skirt and small pin boss diameter to help reduce weight.
  • Lightweight titanium valves (first ever on an ATV) and load-reduced springs are super light, minimizing reciprocating mass for fast-revving, hard-hitting power delivery across the RPM range.
  • High-performance stainless steel exhaust header (and heatshield) is mated to a USFS-approved spark arrestor which looks trick and resists corrosion.
  • The large-capacity radiator is optimally mounted in the frame to keep the center of gravity low but away from mud or rock damage and provides outstanding cooling efficiency.
  • Additional weight-saving engine features include: magnesium cylinder head cover & right side crankcase cover; small-design cam chain tensioner and oil pump; aluminum oil hose; and light CDI ignition unit.
  • Ignition coil is integrated into the spark plug cap, the first time ever used on an ATV, and is extremely light and compact.
  • Smooth-shifting YZ-spec ratchet-type manual 5-speed transmission delivers engine’s potent powerband to the ground with maximum efficiency and hook-up.
  • Heavy-duty manual clutch features extra-thick plates specifically designed for the YFZ450.
  • Large capacity airbox features no-tool access to the oiled dual foam filter for easy maintenance.
  • Trick, works-style clutch lever features oversize barrel adjuster for easy, no tool adjustability of lever/cable play.


  • State-of-the-art high-tensile steel chassis utilizes the most advanced suspension technology ever fitted to an ATV for pure-competition-spec performance right off the showroom floor.
  • Independent aluminum upper A-arm front suspension features fully adjustable competition-spec Kayaba piggyback shocks with 9.1" of travel and separate adjusters for preload, rebound and compression damping.
  • Rear suspension system is a YZ linkage-type that features fully adjustable Showa shock with 10.1" of travel and separate adjusters for preload, rebound and compression damping.
  • Ultra-rigid cast aluminum swingarm reduces weight and ensures optimal, flex-free suspension action.
  • Numerous aluminum components—including the swingarm, upper A-arms, oil tank and wheels —help keep overall dry weight down to a paltry 350 pounds, making this the lightest weight 4-stroke sport ATV ever.
  • Lightweight front and rear master cylinders, combined with twin 160mm front discs with twin-piston calipers and single 200mm rear disc, deliver incredible stopping power with progressive control and feel.
  • Yamaha's YFZ450Ultra-compact, race-bred chassis design creates a short 50.4" wheelbase and low center of gravity to create a super-tight turning radius.
  • Removable aluminum die-cast rear subframe removes easily for maintenance.
  • Long, low and narrow YZ-style seat is only 31.5" high which enhances the low center of gravity for quick, balanced steering and optimal rider movement.
  • High-performance 21 x 7R-10 front and 20 x 10R-9 rear Dunlop radials, designed specifically for the YFZ450, deliver superb, class-leading traction.
  • Lightweight aluminum wheels help enhance suspension performance by reducing unsprung weight.

Additional Features:

  • Aggressive YZ-inspired styling of front cowl, tank, fenders and seat establishes this machine’s pure competition purpose.
  • Dual 30-watt multi-reflector halogen headlights set back in the front cowl add the perfect menacing appearance. Taillight has an incorporated brake light for added convenience.
  • Rugged 45mm-wide serrated footrests provide excellent grip and rider comfort.
  • Large-capacity, 2.6 gallon fuel tank ensures excellent range.
  • Easy-to-use, toggle link-type handlebar-mounted parking brake can be set with one hand.

2004 YFZ 450 Specifications


  • Type: 439cc, 4-Stroke Single, Liquid Cooled w/ Fan, Titanium 5-Valve DOHC
  • Bore x Stroke: 95mm x 62mm
  • Compression Ratio: 11.9:1
  • Carburetion: Keihin 39mm FCR w/ Throttle Position Sensor
  • Ignition: DC - CDI
  • Starting System: Electric
  • Transmission: 5-Speed Manual Clutch Drive Train 2WD; Sealed O-Ring Chain


  • Suspension/Front: Independent Double Wishbone, 9.1” w/ Compression and Threaded Preload Adjustment
  • Suspension/Rear: Aluminum Swing Arm, 10.1” w/ Rebound, Compression and Threaded Preload Adjustment
  • Brakes/Front: Dual Hydraulic Disc, Twin Piston
  • Brakes/Rear: Hydraulic Disc
  • Tires/Front: AT21 x 7-10 Radial
  • Tires/Rear: AT20 x 10-9 Radial


  • L x W x H: 72.4” x 46.1” x 42.9”
  • Seat Height: 31.5”
  • Wheelbase: 50.4”
  • Ground Clearance: 4.4”
  • Fuel Capacity: 2.6 Gallons
  • Dry Weight: 350 Lbs.


  • Yamaha's YFZ450Lighting: Dual 30W Krypton Multi-reflector Headlights & 21/5W Brake light
  • Colors: Team Yamaha Blue/White; White/Red
  • Warranty: 6 Month (Limited Factory Warranty)
  • MSRP: $6,899* Available from June 2003 - *Price and specifications subject to change without notice.

Share This Talk About This In Our Forums