ID # 17801669

2021 Yamaha YZ250FX

Overview

Based on the championship-winning YZ250F and boasting a wide range of cross-country features, the 2020 YZ250FX is a true "out-of-the-box" hare scramble/cross-country competition machine. Yamaha’s exclusive Power Tuner app makes it easy to tune for varied track and trail conditions using your smartphone.


ENGINE
The YZ250FX engine includes all the same race-winning technologies as the previous-generation YZ250F, plus modifications to the cylinder head, exhaust system, fuel injection, drivetrain, electrical system and more. The result is improved peak power, better power delivery, and even tougher durability.

WIRELESS POWER TUNER APP
Yamaha's exclusive Power Tuner app puts the flexibility and precision tunability of the GYTR Power Tuner into your smartphone. Make fuelling and ignition timing changes instantly and upload them to the bike for the ultimate in trackside tuning.
PURPOSE-BUILT TO WIN
With the electric starting system, 8.2-litre fuel tank, rugged plastic skid plate, 18-inch rear wheel and XC racing tires, the YZ250FX is ready to win right out of the box.
 
 Features & Benefits
   
ENGINE
  • "Reversed" liquid-cooled, 250 cc, DOHC, 4-valve (titanium), single-cylinder engine with fuel injection. The engine has been tuned specifically for XC/woods racing with a broad, easy-to-use powerband and excellent power characteristics throughout the rev range.
  • Rearward-slanted, reversed cylinder design.
    • rearward slant moves a significant amount of rotating weight toward the centre of the chassis
    • rearward-slanted cylinder centralizes mass for excellent handling and a light, agile feel
  • "Reversed" engine design (FI system is front-mounted, exhaust exits from rear of cylinder).
    • forward-mounted FI provides straight intake path into the cylinder and provides optimum fuel/ air filling and flow for excellent power
    • front-mounted intake design keeps fuel cooler since engine heat has less effect on incoming fuel (cooler fuel is more dense and increases power)
    • design also helps centralize mass for light, agile handling
  • Electric start with auto decompression system (no kick starter). Unit can be re-started in any gear.
    • there is no main ignition switch on this model
    • electric start button (RHS handlebar) activates the entire electrical system
    • kill switch (LHS handlebar), if held for a few seconds, shuts down entire electrical system
  • Lightweight titanium valves and optimized valve springs.
    • titanium valves reduce reciprocating weight and allow for a higher rpm limit before valve float
    • titanium valves means a fast-revving engine with smooth power delivery
    • 31 mm titanium intake valves and 25 mm titanium exhaust valves
  • Automatic cam chain tensioner.
    • reduces maintenance
    • special cam chain "sliders" reduce internal friction losses
  • Lightweight, short-skirt, forged aluminum piston.
    • light flat-top piston features lateral ribs on both sides of the piston pin area
    • single compression ring and specially designed oil control ring increases surface contact area for optimal sealing
    • 2-ring design decreases sliding resistance, reduces weight and provides faster throttle response
  • Lightweight piston pin features a diamond-like coating (DLC) to reduce friction.
  • Piston oil cooler jet nozzle directs oil to the desired portion of the cylinder and underside of piston.
    • reduces piston, cylinder and rod temperatures for excellent durability
  • "Liner-less" lightweight aluminum cylinder with ceramic composite coating.
    • ceramic coating sprayed directly on the aluminum block, eliminating the need for a liner and reducing weight
    • excellent heat dissipation for consistent power delivery
    • coating enhances the thin film of oil between cylinder and piston, reducing friction and increasing power
  • Cylinder and crankcase "cutaways" allow air "trapped" under the piston to enter special chambers or cutaways.
    • reduces horsepower-robbing "pumping losses"
    • crankcase cutaways match cylinder cutaways for maximum efficiency
  • Ball-bearing-style crankshaft.
    • bronze thrust washers located between crank webs and rod
    • heat-treated for strength and durability
    • balance ratio of the crank is optimized for minimal vibration and good torque feeling
  • Nickel-chromium-molybdenum connecting rod.
    • excellent strength and durability
  • Lightweight, gear-driven counter balancer shaft.
    • reduces vibration for improved rider comfort and less rider fatigue
  • 6-speed transmission utilizes a 2-bar, floating shift guide system and a 14 mm shift shaft.
  • Heavy-duty, multi-plate clutch features a quick access magnesium outer cover.
    • low-friction bushing on actuation arm reduces lever pull effort
    • clutch is designed for the rigours of cross-country
    • outer cover provides fast and easy clutch access
  • 44mm Keihin throttle body fuel injection system.
    • 10-hole injector
    • maximizes fuel atomization for optimal combustion and excellent power delivery
    • FI benefits include automatic adjustments to insure the optimum fuel - air ratio regardless of outside air temperature and altitude
    • other benefits include excellent starting and excellent throttle response
    • cold start knob also doubles as an idle adjuster
  • Handlebar-mounted engine trouble and low fuel warning lights.
  • Exclusive Power Tuner app.
    • Groundbreaking technology brings the power of the GYTR Power Tuner to your iOS or Android device
    • onboard wifi allows adjustment of air/fuel mixture and ignition timing maps based on track conditions
    • record race log information and monitor a range of data such as maintenance and system diagnosis, engine run time and more
    • CCU is adopted to accommodate new Power Tuner
  • Forward-mounted air box features a washable, dual-stage, foam air filter.
    • airbox cover features flush mounted quick release fasteners
    • no tools required to access air filter
    • washable foam filter reduces tune up costs
  • 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.
  • Compact, lightweight, single-core, YZ250F-based dual radiators.
    • outstanding cooling efficiency
    • pre-wired for accessory cooling fan - fits on right side rad only
  • Maintenance-free transistor controlled ignition (TCI).
    • produces a strong spark for fast starts
    • provides precise ignition timing / mapping for optimum engine performance at all rpms
  • High-capacity AC magneto eliminates need for a battery.
  • Wrap-around exhaust system to match head, cam and intake.
    • exhaust exits from the rear of the engine and circles cylinder body
    • wrap-around design ensures the optimum tuned header length
    • maximizes exhaust "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 AMA regulations
  • Works-style, race-spec "barrel adjuster" for on-the-fly clutch lever free play adjustments.
  • Heavy-duty plastic engine skid plate
  • Excessive lean angle sensor
    • Will shut down the engine if the bike lays on its side
    • helps prevent costly engine damage
 CHASSIS/SUSPENSION
  • Compact bilateral beam aluminum frame.
    • frame design centralizes mass for exceptional handling and agility
    • frame offers an optimum balance between strength, rigidity and tuned flex, plus excellent shock absorbing qualities
    • frame design offers excellent rider-machine communication (a.k.a. feedback)
  • Lightweight, tapered aluminum swingarm.
    • lightweight design reduces unsprung weight for excellent suspension performance
    • excellent rear wheel traction and control
    • large 25 mm rear axle
  • Lightweight detachable rear sub frame.
    • constructed of square-section, lightweight aluminum pipe with no bends
    • allows easy access when servicing rear suspension components
  • YZ250F-based, 48 mm, adjustable, inverted, Kayaba "SSS" cartridge fork offers 310 mm (12.2") of wheel travel.
    • fork seal design features a scraper for better cleaning performance in muddy conditions
    • valving and settings are optimized for cross-country racing
    • front fork adjustments include: 20-way compression damping and 20-way rebound damping
    • optional fork springs are available through Genuine Yamaha parts.
  • Fork features a twin-chamber, "Speed Sensitive System" design
    • damper unit is in a separate structure (completely separated air and oil chambers)
    • helps prevent aerated fork oil from entering the inner damper assembly and degrading its damping abilities
    • since the inner damper is pressurized; it also eliminates bubbles forming in the oil
  • Fork also features a Transfer Control Valve (TCV).
    • TCV enhances damping from mid to full stroke and improves bottoming characteristics
    • TCV offers more precise control throughout the full suspension stroke
    • TCV is located on the upside of the spring and its function is controlled by piston speed, not piston position, hence the term "Speed Sensitive System fork".
  • Large wrap-around plastic fork protectors provide excellent lower fork tube protection.
    • self-supporting design reduces friction for smoother fork operation.
  • YZ250F-based, Monocross link rear suspension features a fully adjustable Kayaba piggyback shock with 318 mm (12.5") of wheel travel.
    • valving and settings are optimized for cross-country racing
    • shock features separate adjusters for high- and low-speed compression damping
    • shock adjustments include: threaded spring preload, 20-way low-speed compression damping, 2 turns of high speed compression damping and 30-way rebound damping
  • Adjustable handlebar holders offer a total of 4 different handlebar positions with an adjustment range of 30mm.
    • suits wide variety of rider sizes
    • handlebar holders are rubber mounted for reduced vibration and improved rider comfort
  • Large 270mm floating front "wave-style" disc and compact Nissin twin-piston caliper.
    • wave disc design reduces weight and improves cooling
    • high-friction brake pads
    • excellent braking performance
  • "Shorty-style" adjustable front brake lever can be adjusted to fit various hand sizes.
  • 245 mm rear disc brake uses a "wave-style" disc and single piston Nissin caliper and Nissin master cylinder.
  • Rear caliper and lower portion of the disc are protected by heavy duty plastic protectors.
  • Lightweight, plastic resin 8.2 litre fuel tank is located under the seat.
    • reduces centre of gravity and centralizes mass for exceptional handling performance
    • tank can be flipped on its back without disconnecting fuel line (easy servicing under the tank)
    • compact in-tank electric fuel pump
  • Handlebar-mounted engine trouble and low fuel warning lights
  • Compact bodywork.
    • minimizes weight and enhances the lightweight feel and look of the YZ250FX
    • flat design, "minimal" bodywork allows for fast, easy rider movements and a natural riding position
    • minimal design aids in keeping the body looking good (less plastic to scratch or damage)
    • graphics are impregnated directly into the plastic rad shrouds and will not peel off or get damaged by pressure washing
  • Flat seat design.
    • provides easy rider movements
    • features a "cap cover" to access the fuel cap
    • non-slip seat cover material resists clogging with dirt or mud
  • Rugged, 21" (1.60 x 21) front and 18" (1.85 x 18) D.I.D. rear rims.
    • excellent durability
    • reduce unsprung weight for optimal suspension performance and handling
    • 18" rear wheel improves puncture resistance (Vs. 19" designs)
    • Dunlop AT81 tires
DETAILS

 

 

  • Convenient oil level sight glass
  • Lightweight, extra wide foot pegs
  • Folding shift lever tip helps prevent damage
  • Lightweight chain guide / support helps reduce chance of chain derailment and helps protect rear sprocket
  • Heavy duty rubber swingarm protector (chain)
  • Heavy duty sealed "O" ring drive chain
  • Clutch cable features integrated silicone grease and Teflon liner for smooth cable operation
  • Easy access Yamaha Diagnostic tool connector
  • Sealed, no spill, gel type, low maintenance battery (note: any motorcycle battery must be regularly charged during winter storage)
Specifications
Model
YZ
Category Name
Motorcycles
Year
2021
Manufacturer
Yamaha
Color
Yamaha Racing Blue
Width
825 mm (32.5'')
Engine
Liquid-cooled, DOHC, 4-valve (titanium), single
Height
1,280 mm (50.4'')
Length
2,165 mm (85.2'')
Wheelbase
1,465 mm (57.7'')
Lubrication
Wet sump
Seat Height
965 mm (38'')
Fuel Delivery
44 mm Keihin throttle body F.I.
Bore And Stroke
77 x 53.6 mm
Ground Clearance
325 mm (12.8'')
Compression Ratio
13.5:1
Ignition / Starting
TCI / Electric