Be ahead of the pack when the gate drops with the 2018 YZ450F! The ultimate motocrosser gets a host of updates giving it more competitive power with the push of a button thanks to the addition of electric start. A newly developed chassis, head-turning style, and an all-new Power Tuner app to fine-tune engine settings right from your smart phone will get you on top of the podium box.
Power: The 449 cc reversed, rear slanting engine receives a new intake port design and new piston head with optimized underside rib shapes making it lighter and stronger. The result is a higher compression ratio at 12.8:1 delivering a more competitive power.
Chassis: To enhance handling and heighten performance on rougher terrain, the bilateral beam frame of the new 2018 YZ450F has been updated to include a straight-line fuel tank rail, re-positioned tension pipes, and newly positioned engine mounts. A lightweight, slimmer air cleaner box combined with a new compact fuel tank and seat gives the rider greater freedom to move around while searching for optimal body positioning.
Styling: Newly designed air ducts, side covers, and more visually aggressive front fender highlight the styling changes for the 2018 YZ450F. Two colour variations are available including the traditional Yamaha Racing Blue and a fresh look on the secondary option with a white, cyan, and black colour palette.
Power Tuner App: The new Power Tuner app with expanded functions for the YZ450F not only makes it easy to modify the fuel maps directly from your smart phone, but also allows you to share settings among your team or with friends. The easy to operate Power Tuner app was developed to work on both Apple and Android platforms and is available as a free download from either the Apple App Store or Google Play.
- Engine: Liquid-cooled, DOHC, 4-valve (titanium), single
- Displacement: 449 cc
- Bore and Stroke: 97 x 60.8 mm
- Compression Ratio: 12.8:1
- Fuel Delivery: Keihin 44mm throttle body F.I.
- Lubrication: Wet sump
- Ignition / Starting: TCI / Electric
- Transmission: 5-speed transmission: primary ratio 2.609 (60/23); secondary ratio 3.692 (48/13); 1st gear 1.929 (27/14); 2nd gear 1.533 (23/15); 3rd gear 1.300 (26/20); 4th gear 1.091 (24/22); 5th gear 0.952 (20/21)
- Final Drive: Chain
- Suspension (Front): Adj. 48mm, inverted fork / 310mm (12.2 in.) wheel travel
- Suspension (Rear): Fully adj. Monocross / 317 mm (12.5 in.) wheel travel
- Brakes (Front): 270 mm, floating disc / twin piston caliper
- Brakes (Rear): 245 mm, disc / single piston caliper
- Tires (Front): 80/100-21
- Tires (Rear): 120/80-19
- Length: 2,185 mm (86)
- Width: 825 mm (32.5 in.)
- Height: 1,285 mm (50.6 in.)
- Wheelbase: 1,485 mm (58.5 in.)
- Ground Clearance: 330 mm (13 in.)
- Seat Height: 980 mm (38.6 in.)
- Fuel Capacity: 6.2 L (1.4 Imp. gal.)
- Wet Weight: 111 kg (245 lb.)
- Colour(s): Purplish White, Yamaha Racing Blue
Key Improvements For 2018
- New electric starting with lightweight starter motor & lithium ion battery with BMS
- New wireless smart phone based Power Tuner with expanded functions
- Revised rearward cylinder slant & engine mounts
- Revised cylinder head & compression ratio
- Revised intake & exhaust cam profiles, timing & valve springs
- New lightweight piston & revised piston pin with DLC coating
- New lightweight ACM & new ECU
- Revised air box cover & air filter
- New Mikuni FI throttle body
- Revised exhaust header & muffler mount
- Revised rads
- Revised clutch & transmission
- New frame & revised swingarm
- Revised triple clamps, fork & piggyback shock
- Revised front & rear rims
- New lightweight aluminum handle bar & new lightweight 520 drive chain
- New lighter 6.2L fuel tank, body work & flat design seat
- Revolutionary reversed engine design with front mounted FI system & rear exiting exhaust
- Mass centralizing rearward-slanted-cylinder helps keeps weight centred in the chassis
- Electric starting & lithium ion battery
- Launch Control System
- "Battery-less" 44 mm Mikuni throttle body FI & easy access air box
- Compact aluminum Bilateral Beam frame & aluminum swingarm
- Industry-leading, fully adjustable KYB® "SSS" fork & Monocross rear suspension
- 270 mm front & 245 mm rear disc brakes
- Revised, "reversed", liquid-cooled, 449 cc, DOHC, 4-valve (titanium), fuel injected, single with electric start: super convenient electric starting means faster re-starts & significantly reduced rider fatigue; compact electric starter powered by a lightweight lithium ion battery
- All new electric starting: super convenient electric starting means faster re-starts & 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 & 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 & 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 & power losses; 37 mm titanium intake valves & 30.5 mm titanium exhaust valves; 4-valve design offers optimum flow for excellent power & torque; intake port shape has been revised for 2018; re-located engine mounting "bosses" have been moved to the rear of the cylinder head; new aluminum upper engine mounts
- 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)
- Revised high lift intake & exhaust cams & valve springs: intake & exhaust cam profiles & cam timing have been revised for increased power output; valve spring size & 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 & improve performance... titanium valves are 40 to 45 % lighter than steel valves; reduced valve weight improves valve train reliability & longevity; reduced reciprocating weight allows for a higher rpm limit & better control of the valves
- Automatic cam chain tensioner: reduces maintenance & 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 insures faster, more uniform heat dissipation; ceramic coating enhances the thin film of oil between the cylinder & piston, reducing friction & increasing power
- Cylinder is "offset" relative to the crankshaft (to exhaust side): reduces frictional losses between piston & 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
- New, lightweight, short-skirt, forged aluminum piston & piston pin: new piston design increases the compression ratio from 12.5:1 to 12.8:1; piston weight is reduced by 6 grams & features new under side ribs for additional strength; lightweight design means faster throttle response & reduced mechanical vibration for excellent durability; New, DL (diamond like) coating on piston pin & special coating on piston skirt reduces frictional losses
- Piston oil cooler jet nozzle directs oil to the cylinder, rod & underside of piston: reduces piston, cylinder & rod temperatures for excellent durability
- Carburized connecting rod for excellent durability: carburization is a type of heat treating that adds strength & hardness
- Lightweight gear driven balancer shaft: reduces vibration for improved rider comfort & reduced rider fatigue
- Revised, heavy duty clutch with quick access magnesium outer cover & on the fly "barrel adjuster.": revised pressure plate features new reinforcing ribs for improved clutch feeling; revised clutch springs & specially machined steel plates; quick access outer cover provides fast & 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, 5-speed transmission utilizes a 2-bar, floating shift guide system & a 14 mm shift shaft: newly designed 2nd, 3rd & 4th gears are wider to match the increased engine power; floating shift guide system provides smooth, positive shifts; 14 mmm shift shaft provides good durability in the event of a crash; see spec page for gear ratios (ratios are unchanged Vs. 2017)
- New, lightweight, 44 mm Mikuni throttle body fuel injection system: 12-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 throttle response & starting; cold start knob (FID) also doubles as an idle adjuster
- The injector spray pattern, spray direction and the distance to the intake valves have been optimized. Forward mounted straight intake tract helps to maximize the benefits of the FI system & overall power output: super convenient, smart phone based power tuner; no "hard" link required between the unit & smart phone... wireless signal via Wi-Fi; app is free... will work with either ISO or Android platforms; receiving communication control unit (CCU) is located under left side cover of bike; expanded adjustment range ? 16 settings for both fuel injection duration & ignition timing; new "real time" machine monitoring function (engine rpm, throttle angle, battery voltage, coolant temp, intake air temp, outside air pressure, etc.); new maintenance function ? reminds you when scheduled maintenance is required; new race log function is available to record & save settings from various tracks; tuning maps & race logs can be shared via email, Air Drop etc.
- All new, smart phone based, wire-less, "Power Tuner" with expanded functions: super convenient, smart phone based power tuner; no "hard" link required between the unit & smart phone... wireless signal via Wi-Fi; app is free... will work with either ISO or Android platforms; receiving communication control unit (CCU) is located under left side cover of bike; expanded adjustment range ? 16 settings for both fuel injection duration & ignition timing; new "real time" machine monitoring function (engine rpm, throttle angle, battery voltage, coolant temp, intake air temp, outside air pressure, etc.); new maintenance function ? reminds you when scheduled maintenance is required; new race log function is available to record & save settings from various tracks; tuning maps & race logs can be shared via email, Air Drop etc.
- Revised 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 with new securing clips
- 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 for fast, easy oil changes: Revised, single core, dual radiators provide outstanding cooling efficiency.; core size has been increased while upper & lower tank sizes have been decreased; actual cooling area of the rads has been increased approx. 4%; mounting angle of the rads, shrouds & cooling louvers have been revised for increased air flow
- 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 high capacity AC magneto: smaller, lighter ACM means less engine rotational resistance
- Revised, lightweight, wrap-around exhaust system: exhaust exits from the rear of the cylinder & circles cylinder body; revised "1st stage" header has been lengthened to ensure 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; new muffler rubber mounting system reduces vibration & improves durability
- Launch control system (LCS): provides smoother, quicker starts with less wheel spin & front wheel lift; allows rider to concentrate on clutch control, body position & machine; system functions in 1st & 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 & wheelies; activation button is on the LHS handlebar & 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
New, compact body work: newly designed bodywork reduces weight, improves rider mobility & enhances the lightweight feel & look of the YZ450F (new items: front fender/ rad shrouds / air box cover /gas tank / side covers / rear fender); flat design, "minimal" bodywork allows for fast, easy rider movements & a natural riding position; minimal design aids in keeping the body work 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 washingRevised, flat design seat: seat is narrower in the fuel tank — seat junction (Vs. '17 model) for better knee grip & easier rider movements; seat is flatter for easier rider movements; front of seat features a quick remove "cap cover" to access the fuel capNew, lightweight front & rear rims: new lighter design reduces unsprung weight for optimal suspension performance & handling; excellent strength & durability due to new cross sectional rim design; front rim size is 1.60 x 21", rear is 2.15 x 19"; rear hub features second bearing on sprocket side for increased rigidity & durabilityLithium ion battery: lightweight, compact battery & under seat, lightweight composite battery box; special battery management system (BMS) with "self-protection" mode monitors & maintains battery condition
- New, compact, lightweight "Bilateral Beam" aluminum frame: new frame offers an optimum rigidity balance between strength, rigidity & tuned flex, while also providing excellent shock absorbing qualities; frame design is new with the steering head moved forward (Vs. last generation) ? resulting in a 5 mm longer wheelbase for improved traction & stability; new, top frame rails (aka. tank rails) are a straight design (Vs. last generation's slight S bend); upper engine mounts are moved rearward to provide optimized front frame rigidity & tuned flex; swingarm pivot area is wider (Vs. last generation) improving bump stability & traction
- Revised, lightweight, tapered aluminum swingarm: swingarm is slightly shorter (Vs. 2017) and 3.6% lighter; lightweight design reduces unsprung weight for optimum suspension performance; excellent rear wheel traction & control; 25mm rear axle
- Lightweight detachable rear sub frame: constructed of square-section, lightweight aluminum pipe with no bends; allows easier access when servicing rear suspension components; detachable design reduces costs in the event of a loop out
- Revised upper & lower triple clamps: fork off set is 22 mm (Vs. 25 mm for 2017)
- New, light weight, high strength, tapered aluminum handlebar: suits wide variety of rider sizes; handle bar holders are rubber mounted for reduced vibration & improved rider comfort
- Adjustable handlebar holders offer a total of 4 different handlebar positions with an adjustment range of 30 mm (1.2"): suits wide variety of rider sizes; handle bar holders are rubber mounted for reduced vibration & improved rider comfort
- Revised, 48mm, adjustable, inverted, KYB "SSS" cartridge fork with 310mm (12.2") of wheel travel: cylinder diameter has been increased from 24 to 25 mm for improved damping; mid speed valve is changed from coil spring to "leaf spring" style; friction reducing coating on inner tubes for reduced stiction; 22 mm front axle; front fork adjustments include: compression & 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; the inner damper is pressurized, eliminating 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".
- Large "wrap-around" plastic fork protectors provide excellent lower fork tube protection: "self-supporting" design reduces friction for smoother fork operation
- Revised, Monocross link rear suspension with 317 mm (12.5") of wheel travel: fully adjustable KYB piggyback shock features a larger sub tank, new lighter spring & revised damping settings; separate adjusters for high- and low-speed compression damping; shock is in-line with the center axis of the frame for excellent control; shock adjustments include: threaded spring preload, low & high speed compression damping, & rebound damping
- 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); excellent braking performance; "shorty style" adjustable front brake lever can be adjusted to fit various hand sizes
- 245 mm rear disc brake features a "wave-style" disc & single piston Nissin caliper: revised rear rotor for improved heat resistance; rear caliper & lower portion of the disc are protected by heavy duty plastic protectors.
- New, 6.2 litre lightweight plastic resin fuel tank: tank is positioned under the seat to reduce the centre of gravity & centralizes mass for exceptional handling & a lightweight feeling compact in-tank electric fuel pump
NOTE: Lithium ion batteries must be charged using the correct type of charger. Yamaha recommends using only the Optimate Lithium TM291 battery charger. Do not use a high powered, lead acid charger or an automatic de-sulphating lead acid charger or serious battery damage will occur. Never use jumper cables to start the engine connected to a lead acid battery. YDT (Yamaha Diagnostic Tool) easy access, under seat coupler: Yamaha's exclusive money & time saving diagnostic tool
- New, lightweight 520 drive chain
- Extra wide foot pegs provide excellent grip
- Convenient oil level sight glass
- Folding shift lever tip helps prevent damage
- Lightweight Sun Star rear sprocket
- Heavy duty rubber swingarm protector
- Lightweight chain guide / support helps reduce chance of chain derailment & helps protect rear sprocket
- Clutch cable features integrated silicone grease & Teflon liner for smooth cable operation
Every attempt has been made to showcase Canadian versions of our products, but all images, information and specifications may not be exact and are subject to change without notice. Some models may be shown with optional accessories.