CHAMPIONSHIP YZ DNA TUNED FOR X‑COUNTRY.
YZ250F championship‑tech in a light, powerful machine built to win X‑Country races.
The high flying, high paced action of motocross is not for everyone. As a result, the slightly less intense world of cross country / harescramble racing is experiencing solid growth and interest. The YZ250FX is a cross country focused model with the performance potential of the YZ250F. If you are serious about winning, the YZ250FX could be the machine for you. Check out the impressive list of improvements for 2017.
Convenient, dependable electric start ensures hassle-free, push button start.
The YZ250FX uses the “Best in Class” YZ250F reversed cylinder, rearward slanted engine with modified fuel injection settings, electric starting and a 6-speed transmission. With the optional GYT-R YZ Power tuner, you can adjust both fuel mapping and ignition mapping to best suit conditions and riding ability.
Featuring KYB “SSS” forks and a fully adjustable KYB rear shock, the FX uses the same suspension as its MX cousin with softer settings and slightly more rear wheel travel. Also included is a lightweight aluminum side stand and an 18″ rear wheel. With a maximum noise output of 94 dB, the muffler is the same as the current YZ250F.
2018 Yamaha YZ250FX Totalmotorcycle.com Key Features
- Latest generation YZ250F based rear slanting engine & Bilateral Beam chassis
- Forward mounted fuel injection & wrap around exhaust
- Electric starting
- YZ based, fully adjustable KYB suspension
- 18 inch rear wheel
- Adjustable handlebar
- GYTR Power Tuner compatible
- New cylinder head with revised intake & exhaust port shapes
- Revised intake & exhaust camshafts & valve springs
- Revised intake tract & intake manifold
- Revised piston, piston pin & oil jet nozzle
- Revised connecting rod & crankshaft
- New crankcase heat treating process
- Revised 6-speed transmission & gear shift lever
- Revised airbox cover & fasteners
- Revised wrap around exhaust header pipe
- Revised ECU
- Revised frame & engine mounts
- Revised fork seals
- New larger 270 mm front disc
- Optimized suspension settings
- Revised fork seal design features a new scraper
- New, engine trouble & low fuel warning lights
- Kickstarter has been discontinued to save weight (available as an accessory)
- 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 & helps protect rear sprocket
- Heavy duty rubber swingarm protector (chain)
- Heavy duty sealed “O” ring drive chain
- Clutch cable features integrated silicone grease & Teflon liner for smooth cable operation
- Easy access GYTR Power Tuner & Yamaha Diagnostic tool connectors
- Sealed, no spill, gel type, low maintenance battery (note: any motorcycle battery must be regularly charged during winter storage)
- Innovative Hare Scramble/GNCC® Engine Design
Based on the championship-winning YZ250F™, featuring Yamaha’s revolutionary rearward slanted, liquid-cooled, DOHC 4-stroke power plant with forward-positioned straight downdraft symmetrical intake, and with an added sixth gear and wide ratio transmission, the YZ250FX™ is an “out-of-the-box” Hare Scrambles/GNCC® competition machine.
- High-Spec Engine
The engine is based on the 2017 YZ250F, and includes all the same race-winning features: an updated cylinder head, lightweight forged, two-ring, flat-top piston; a shorter, more durable piston pin with diamond like carbon (DLC) coating; a revised piston oil jet, and advanced connecting rod, crankshaft, and counterbalancer designs. Together, the result is improved peak power, power delivery and overall durability.
- 6-Speed Transmission
A wide-ratio 6-speed transmission is used to insure the right gear is available for the wide variety of terrain found in cross-country racing.
- Tuned Chassis
Nearly the same bilateral beam frame that is found on the championship winning YZ250F is used on the YZ250FX. The forged section at the swingarm pivot and engine mounting brackets help develop nimble lightweight feeling in the tight technical terrain while still providing stability in fast sections.
- Advanced Suspension
Industry-leading, fully adjustable KYB® spring-type fork with speed sensitive damping features revised valving for improved suspension feel and balance. The linkage type rear suspension features a KYB rear shock with settings optimized for cross country racing.
- Cross Country Features
With the electric starting system, a 2-gallon 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.
2018 Yamaha YZ250FX Totalmotorcycle.com Features and Benefits
- Revised, “reversed” liquid-cooled, 250cc, DOHC, 4-valve (titanium), single with fuel injection. The engine has been tuned for excellent “ride ability & controllability” and delivers a broad, easy to use power band with excellent power characteristics throughout the rev range. 2017 model changes improve power delivery in both low to mid and mid to top end performance.
- 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 & 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 & provides optimum fuel/ air filling & 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 & increases power)
- design also helps centralize mass for light, agile handling
- Electric start with auto decompression system. Unit can be re-started in any gear.
NOTE: kick starter has been discontinued / removed (available as an accessory).
- 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
- removal of kick starter & related gears etc. reduces weight
- Revised, 4-valve cylinder head features a 13.5:1 compression ratio.
- intake port has been raised 4 mm (Vs. ’16) for improved flow
- larger diameter intake valve seats improve flow
- improved power delivery across the rev range (low, mid & top)
- 4-valve design offers optimum flow & excellent power
- Lightweight titanium valves & revised load optimized valve springs.
- titanium valves reduce reciprocating weight & allow for a higher rpm limit before valve float
- intake & exhaust valve spring size have been increased to match revised cams
- titanium valves means a faster-revving engine with smooth power delivery
- 31 mm titanium intake valves & 25 mm titanium exhaust valves
- Shorter internal air box funnel & new intake manifold with larger cross section.
- improved fuel – air flow for increased power
- improved over-rev feeling
- reduced horsepower losses in the mid to high rpm (reduced friction as fuel-air “charge”
travels thru the intake tract)
- Automatic cam chain tensioner.
- reduces maintenance
- special cam chain “sliders” reduce internal friction losses
- Revised, intake & exhaust camshafts.
- revised intake & exhaust cam profiles (working angle & lift) for improved power & “control-ability”
- hollow design reduces weight
- New, lightweight, short-skirt, forged aluminum piston.
- new, lighter, flat top piston features lateral ribs on both sides of the piston pin area
- 7% reduction in piston weight means faster engine response
- single compression ring & specially designed oil control ring increases surface contact area for better sealing
- 2-ring design decreases sliding resistance, reduces weight & provides faster throttle response
- Revised, lighter weight piston pin features a diamond like coating (DLC) to reduce friction.
- Revised, piston oil cooler jet nozzle directs oil to the desired portion of the cylinder & underside of piston.
- reduces piston, cylinder & 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 & reducing weight
- excellent heat dissipation for consistent power delivery
- coating enhances the thin film of oil between cylinder & piston, reducing friction & increasing power
- Cylinder & 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
- New heating treating process for crankcases.
- heating treating process increases crankcase strength by 5%
- improved crankcase strength matches increased power output
- Revised ball bearing style crankshaft.
- new bronze thrust washers added between crank webs & rod
- heat treated for strength & durability
- balance ratio of the crank has been optimized to reduce vibration & improve torque feeling
- New nickel-chromium-molybdenum connecting rod.
- excellent strength & durability
- increased strength to maintain precise big end roundness during high rpm & high load use
bronze thrust washers on either side of the rod to reduce friction
- Lightweight gear driven counter balancer shaft.
- reduces vibration for improved rider comfort & less rider fatigue
- Revised 6-speed transmission utilizes a 2-bar, floating shift guide system & a 14 mm shift shaft.
- new surface treatment on selected gears for durability
- new, stronger heat treated gear shift lever
- transmission utilizes a 2-bar, floating shift guide system & a 14 mm shift shaft
- good durability in the event of a crash (14 mm shift shaft)
- see spec page for gear ratios
- Revised, heavy duty, multi-plate, clutch features a quick access magnesium outer cover.
- new low friction bushing on actuation arm reduces lever pull / effort
- clutch is designed for the rigours of cross country
- outer cover provides fast & easy clutch access
- 44mm Keihin throttle body fuel injection system.
- 10-hole injector
- maximizes fuel atomization for more complete combustion & excellent power delivery
- FI benefits include automatic adjustments to insure the optimum fuel – air ratio regardless of outside air temperature & altitude
- other benefits include excellent starting & excellent throttle response
- cold start knob also doubles as an idle adjuster
- Injector spray pattern, spray direction & distance to the intake valves have been optimized.
- forward mounted straight intake tract maximizes benefits of the FI system & improves power output
- New, handlebar mounted engine trouble & low fuel warning lights.
- Optional, compact, hand held “GYTR Power Tuner” allows tailoring of both fuel injection duration & ignition mapping.
- 9- different setting points can be accessed for both fuel duration & ignition maps
- maps can be stored & shared with other Power Tuners if desired
- easy access GYTR Power Tuner connector port
- Revised 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 & faster oil changes)
- oil volume is optimized to reduce oil related drag & 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
- Revised ECU with new ignition mapping & fuel mapping for improved power & over rev feeling.
- High capacity AC magneto eliminates need for a battery.
- Revised, wrap-around exhaust system to match head, cam & intake improvements.
- header pipe diameters have been revised for a 12 to 16% flow improvement
- exhaust exits from the rear of the engine & 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 CMRC & AMA regulations
- Works-style race-spec “barrel adjuster” for on-the-fly clutch lever free play adjustments.
- New, 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
- no special procedure to re-start the bike… just kick it and go
- Revised, compact “Bilateral Beam” aluminum frame.
- revised frame with wider spars in the swingarm pivot area (up to 12 mm wider)
- revised engine mounts
- frame & engine designs centralize mass for exceptional handling & agility
- frame offers an optimum rigidity balance between strength, rigidity & 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 & 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
- Revised, YZ250F based, 48mm, adjustable, inverted, Kayaba “SSS” cartridge fork offers 310mm (12.2″) of wheel travel.
- revised fork seal design features a new scraper for improved cleaning performance in muddy conditions
- revised valving & 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 & oil chambers)
- helps prevent aerated fork oil from entering the inner damper assembly & 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 & improves bottoming characteristics
- TCV offers more precise control throughout the full suspension stroke
- TCV is located on the upside of the spring & its function is controlled by piston speed, not piston position, hence the term “Speed Sensitive System fork”.
- Revised fork seal design features a new scraper for improved cleaning performance in muddy conditions
- Large “wrap-around” plastic fork protectors provide excellent lower fork tube protection.
- “self-supporting” design reduces friction for smoother fork operation.
- Revised YZ250F based, Monocross link rear suspension features a fully adjustable Kayaba piggyback shock with 318 mm (12.5″) of wheel travel.
- revised valving & 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 & 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 & improved rider comfort
- New, larger, 270mm floating front “wave-style” disc & compact Nissin twin piston caliper.
- wave disc design reduces weight & improves cooling (wave design offer more surface area for better 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 & single piston Nissin caliper & Nissin master cylinder.
- Rear caliper & lower portion of the disc are protected by heavy duty plastic protectors.
- Lightweight, plastic resin 7.5 litre fuel tank is located under the seat.
- reduces centre of gravity & 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
- New, handlebar mounted engine trouble & low fuel warning lights
- Compact body work.
- reduces weight & enhances the lightweight feel and look of the YZ250FX
- flat design, “minimal” bodywork allows for fast, easy rider movements & 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 & 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 & 18″ (1.85 x 18) D.I.D. rear rims.
- excellent durability
- reduce unsprung weight for optimal suspension performance & handling
- 18″ rear wheel improves puncture resistance (Vs. 19″ designs)
- Dunlop AT81 tires
2018 Yamaha YZ250FX – Totalmotorcycle.com USA Specifications/Technical Details
US MSRP Price: $7,999 USD
Bore x Stroke 77.0mm x 53.6mm
Compression Ratio 13.5:1
Fuel Delivery Keihin® fuel injection, 44mm
Ignition TCI: Transistor Controlled Ignition
Transmission Wide-ratio constant-mesh 6-speed; multiplate wet
Final Drive O-ring chain
Suspension / Front KYB® spring-type fork with speed sensitive
damping; fully adjustable, 12.2-in travel
Suspension / Rear KYB® single shock; fully adjustable, 12.5-in
Brakes / Front Hydraulic disc, 270mm
Brakes / Rear Hydraulic disc, 245mm
Tires / Front 90/90-21 Dunlop® AT81F
Tires / Rear 110/100-18 Dunlop® AT81
L x W x H 85.2 in x 32.5 in x 50.4 in
Seat Height 38.0 in
Wheelbase 57.7 in
Rake (Caster Angle) 26.3°
Trail 4.5 in
Ground Clearance 12.8 in
Fuel Capacity 2.0 gal
Wet Weight 249 lb
Warranty 30 Day (Limited Factory Warranty)
Color Team Yamaha Blue
2018 Yamaha YZ250FX – Totalmotorcycle.com Canadian Specifications/Technical Details
Canada MSRP Price: $9,049 CDN
Liquid-cooled, DOHC, 4-valve (titanium), single
Bore and Stroke
77 x 53.6 mm
44 mm Keihin throttle body F.I.
Ignition / Starting
TCI / Electric
Wide ratio 6-speed transmission
primary ratio 3.353 (57/17)
secondary ratio 3.923 (51/13)
1st gear – 2.385 (31/13)
2nd gear – 1.813 (29/16)
3rd gear – 1.444 (26/18)
4th gear – 1.143 (24/21)
5th gear – 0.957 (22/23)
6th gear – 0.815 (22/27)
“O” ring chain
Adj. 48 mm, inverted fork / 310 mm (12.2″) wheel travel
Fully adj. Monocross / 318 mm (12.5″) wheel travel
270 mm, floating disc / twin piston caliper
245 mm disc / single piston caliper
2,165 mm (85.2″)
825 mm (32.5″)
1,280 mm (50.4″)
1,465 mm (57.7″)
325 mm (12.8″)
965 mm (38″)
7.5 litres (1.7 imp. gallons)
113 kg (249 lb)
Yamaha Racing Blue
2018 Yamaha YZ250FX – Totalmotorcycle.com European Specifications/Technical Details
Europe/UK MSRP Price: £ GBP (On The Road inc 20% Vat)
Manufacturer Specifications and appearance are subject to change without prior notice on Total Motorcycle (TMW).