Conquer Dirt

After a laundry list of significant upgrades in 2018, the YZ450F gets refined for 2019 with optimized suspension settings to further enhance its on-track capability. With highlights including the wireless Power Tuner app, electric start, launch control, a potent fuel-injected four-stroke engine and a race-ready chassis, the ultimate motocrosser is ready to take you straight from the showroom floor to the podium.
 

POWER TUNER APP

The groundbreaking Power Tuner app makes it easy to modify fuel mapping directly from your Smartphone based on track conditions, track maintenance intervals and share settings with teammates or friends. Easy to operate and free to download, the Power Tuner app uses onboard Wi-Fi to communicate with the bike's CCU and allows you to tune like never before.

• Wireless smartphone-based Power Tuner app
• Revolutionary reversed engine design with front-mounted FI system and rear-exiting exhaust
• Mass centralizing rearward-slanted cylinder helps keeps weight centred in the chassis
• Electric starting and lithium ion battery
• Launch Control System
• Compact aluminum Bilateral Beam frame and aluminum swingarm
• Industry-leading, race-ready, fully adjustable suspension

• Reversed, liquid-cooled, 449 cc, DOHC, 4-valve (titanium), fuel injected, single-cylinder engine.
• Electric starting.
  • super convenient electric starting means faster re-starts and significantly reduced rider fatigue
  • compact electric starter powered by a lightweight lithium ion battery
• "Reversed" engine design (FI system is front mounted, exhaust exits from rear of cylinder).
  • FI throttle body and air box are front mounted, providing a straight intake path
  • straight shot intake path provides optimum fuel / air / exhaust flow for excellent power
  • front mounted intake keeps fuel cooler since engine heat has less effect on incoming fuel (cooler fuel is more dense and increases power)
• Rearward slanted, reversed cylinder design centralizes mass.
  • rearward slant has been revised
  • rearward slant moves a significant amount of rotating weight toward the centre of the chassis, centralizing mass for light, agile handling
• Revised, 4-valve cylinder head features a new 12.8:1 compression ratio.
  • compact combustion chamber provides optimum combustion speed while also reducing heat and power losses
  • 37 mm titanium intake valves and 30.5 mm titanium exhaust valves
  • 4-valve design offers optimum flow for excellent power and torque
• New long design electrode spark plug.
  • moves the spark plug tip deeper into the combustion chamber
  • new spark plug cap holder(helps prevent plug cap from being dislodged)
• High-lift intake and exhaust cams and valve springs.
  • intake and exhaust cam profiles and cam timing optimized for increased power output
  • valve spring size and rates have been revised to match the revised cams
  • valve spring rates are optimized to reduce friction related power losses
• Lightweight titanium valves.
  • titanium valves reduce weight and improve performance... titanium valves are 40-45 % lighter than steel valves
  • reduced valve weight improves valve train reliability and longevity
  • reduced reciprocating weight allows for a higher rpm limit and better control of the valves
• Automatic cam chain tensioner.
  • reduces maintenance and mechanical engine noise
  • special cam chain "sliders" reduce internal frictional losses
• Lightweight, ceramic composite-plated "liner-less" aluminum cylinder.
  • reduced weight (no sleeve or heavy liner) plating is sprayed directly on the aluminum block
  • ceramic coating ensures faster, more uniform heat dissipation
  • ceramic coating enhances the thin film of oil between the cylinder and piston, reducing friction and increasing power
• Cylinder is "offset" relative to the crankshaft (to exhaust side).
  • reduces frictional losses between piston and cylinder wall during the power stroke
• Cylinder "cutaways" allow air "trapped" under the piston to enter a side chamber (or cutaway).
  • reduces horsepower-robbing "pumping losses"
• Crankcase also utilizes special "cutaways".
  • reduces horsepower-robbing "pumping losses"
  • crankcase cutaways match cylinder cutaways for maximum efficiency
• Lightweight, short-skirt, forged aluminum piston and piston pin.
  • new piston design increases the compression ratio from 12.5:1 to 12.8:1
  • piston weight is reduced by 6 grams and features new under side ribs for additional strength
  • lightweight design means faster throttle response and reduced mechanical vibration for excellent durability
  • DLC (diamond-like coating) coating on piston pin and special coating on piston skirt reduces frictional losses
• Piston oil cooler jet nozzle directs oil to the cylinder, rod and underside of piston.
  • reduces piston, cylinder and rod temperatures for excellent durability
• Carburized connecting rod for excellent durability.
  • carburization is a type of heat treating that adds strength and hardness
• Lightweight gear-driven balancer shaft.
  • reduces vibration for improved rider comfort and reduced rider fatigue
• Heavy-duty clutch with quick-access magnesium outer cover and on-the-fly barrel adjuster.
  • quick-access outer cover provides fast and easy clutch access
  • light lever pull for reduced hand fatigue during a long moto
  • works-style, race-spec barrel adjuster for on-the-fly clutch lever free play adjustments.
• Revised, heavy duty clutch with quick access magnesium outer cover and on the fly "barrel adjuster."
  • revised pressure plate features new reinforcing ribs for improved clutch feeling
  • revised clutch springs and specially machined steel plates
  • quick access outer cover provides fast and easy clutch access
  • light lever pull for reduced hand fatigue during a long moto
  • works-style race-spec "barrel adjuster" for on-the-fly clutch lever free play adjustments.
• 5-speed transmission with 2-bar, floating shift guide system and a 14 mm shift shaft.
  • 2nd, 3rd and 4th gears are wider to engine power
  • floating shift guide system provides smooth, positive shifts
  • 14 mm shift shaft provides good durability in the event of a crash
• Lightweight, 44 mm Mikuni throttle body fuel injection system.
  • 12-hole injector maximizes fuel atomization for more complete combustion and excellent power delivery
  • FI benefits include automatic adjustments to insure the optimum fuel andmdash; air ratio regardless of outside air temperature and altitude
  • other benefits include excellent throttle response and starting
  • cold start knob (FID) also doubles as an idle adjuster
• Smartphone-based, wire-less, "Power Tuner" app.
  • super convenient, smartphone based Power Tuner
  • no "hard" link required between the unit and smartphone... wireless signal via Wi-Fi
  • app is free and will work with either iOS or Android platforms
  • receiving communication control unit (CCU) is located under left side cover of bike
  • adjustment range includes 16 settings for both fuel injection duration and ignition timing
  • real-time machine monitoring function (engine rpm, throttle angle, battery voltage, coolant temp, intake air temp, outside air pressure, etc.)
  • new maintenance function allows user to track hours of use for scheduled maintenance
  • race log function is available to record and save settings from various tracks
  • tuning maps and race logs can be shared
• Forward-mounted air box with revised washable, dual-stage foam air filter.
  • no tools required to access air filter
  • new air box cover with single quick-release fastener
  • revised, washable dual-stage air filter
• Wet sump lubrication system.
  • reduces weight (no remote oil tank or oil lines)
  • eases maintenance (easier and faster oil changes)
  • oil volume is optimized to reduce oil related drag and weight
• Easy-access "cartridge-type" oil filter for fast, easy oil changes.
  • single-core, dual radiators provide outstanding cooling efficiency
• Maintenance-free transistor controlled ignition (TCI).
  • produces a strong spark for fast starts
  • provides precise ignition timing / mapping for optimum engine performance at any rpms
• Lightweight, wrap-around exhaust system.
  • exhaust exits from the rear of the cylinder and circles cylinder body
  • header length optimized for "pulse effect" for excellent power delivery
  • centralizes mass by moving weight closer to the centre of the chassis
• Lightweight, aluminum, re-packable muffler (aka silencer).
  • sound output is 94 dB meeting CMRC and AMA regulations
  • new rubber muffler-mounting system reduces vibration and improves durability
• Launch Control System (LCS).
  • provides smoother, quicker starts with less wheel spin and front wheel lift
  • allows rider to concentrate on clutch control, body position and machine
  • system functions in 1st and 2nd gears only and is disabled when the bike is shifted into 3rd
  • ECU controls the system and adjusts engine rpm to limit wheel spin and wheelies
  • activation button is on the LHS handlebar and features a LED indicator light.
• Special "G" sensor system.
  • shuts down fuel injection system if bike lies on its side for more than 10 seconds
  • helps prevent costly engine damage
  • no special procedure to re-start the bike... just hit the electric start button and go!