The new 2016 YZ250X is based on the current YZ250 2-stroke with the following additional features that enhance its competitiveness for cross country or enduro type racing / riding.

• Revised engine tuning characteristics (head, ignition, porting & YPVS)
• Revised transmission gear ratios
• Revised clutch
• New expansion chamber shape
• Revised front & rear suspension settings
• New 18" rear wheel
• New aluminum side stand
• New on-off-reserve fuel petcock

• Revised, liquid-cooled, 249cc, piston-reed-valve-inducted, 2-stroke engine is both lightweight and compact. It is also quite simple to maintain or repair versus a modern 4-stroke.
• Revised cylinder head volume with new 7.9:1 compression ratio
• Ceramic composite cylinder bore is a "liner less" design with the ceramic coating sprayed directly on the aluminum block. The benefits include reduced weight (no heavy iron liner), reduced friction, extended cylinder life and excellent heat dissipation for consistent power delivery.
• Revised exhaust port (main) size & timing for optimum cross country / enduro performance
• Revised YPVS power valve system features a total of three slides (one main and two auxiliary slides) which provides the benefits of both solid, low rpm power delivery combined with a strong top-end punch. The YPVS system varies the exhaust port height and timing based on engine rpm. Changes for 2016 include a wider actuation rpm and new valve shape for a broader power band more suited to cross country & enduro type racing or riding.
• Keihin PWK38S carburetor with power jet and throttle position sensor (TPS) ensures precise fuel/air mixing and extra-crisp throttle response throughout the powerband.
• Special-design, 4-petal, carbon fiber reeds provide great throttle response and engine performance across the entire RPM range.
• Revised, smooth-shifting, 5-speed, transmission with heavy-duty, multi-plate wet clutch ensures optimal hook-up for outstanding acceleration and corner-exiting power. Transmission shafts utilize involute splines for smooth, positive shifting even under power. 3rd, 4th & 5th gears ratios are wider for better performance in cross country or enduro type racing or riding.
• Revised internal shift mechanism for smoother shifting even in difficult situations
• Revised clutch features a reduction in spring load (easier clutch pull) for less wrist & hand fatigue during a long event.
• Quick-access, outer clutch cover allows for fast, easy clutch maintenance.
• Trick, works-style clutch lever features a race-spec "barrel adjuster" for on-the-fly clutch adjustments. Lever position can now be set to rider's preference.
• Revised CD (capacitor discharge) ignition system features new timing specs to ensure optimal timing for faster, stronger response across the rpm range.
• Washable, dual-stage, foam air filter reduces maintenance costs.
• Large-capacity, dual radiators feature a 10-row core to deliver maximum cooling efficiency.
• Revised expansion chamber features a slimmer head pipe design for increased protection. The lightweight, aluminum silencer is rebuildable so performance can be maintained at the optimum level and noise levels can be controlled. Noise output is 94 dB.

• Lightweight, aluminum, semi-double-cradle style frame. The obvious benefit of an aluminum frame is a significant reduction in overall machine weight. Yamaha has maintained the semi-double cradle design because it offers an excellent balance between stiff lateral and torsional rigidity while offering more controlled flex in the longitudinal plane. This frame design offers the ideal "rigidity balance" which means it offers the flexibility of a steel frame with the lighter weight of an aluminum frame. This frame provides stiffness where it is required and controlled flexibility in other areas. The result is a super light aluminum frame, which provides excellent handling, good ride quality, excellent stability and responsive cornering performance.
• Removable rear subframe is constructed of square-section, lightweight aluminum pipe. Detachable design allows easy access when servicing rear suspension components.
• Lightweight, tapered, aluminum swingarm is produced using "hydro forming", a special forming method that uses high pressure water to form shapes.
• Cast aluminum upper and forged lower triple clamps provide both lightweight and strength for fast, precise handling.
• Adjustable handlebar mounts allow the handlebars to be moved 10mm rearward if desired.
• Revised, "Speed Sensitive System" 48mm, adjustable, inverted, Kayaba cartridge fork features a twin-chamber design. The twin chamber design means the damper unit is in a separate structure which prevents 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. The Speed Sensitive System design means the damping force is controlled by the piston speed in the fork, not its position.
• This fork also features a Transfer Control Valve (TCV) . The TCV enhances the damping force of the inner damper from mid stroke to full stroke and improves bottoming characteristics. The benefit of TCV is more precise control throughout the full stroke range.
• Kashima coating on the fork tubes reduce friction for smoother suspension performance. Low friction oil seals also provide reduced stiction for a smoother stroke. Front wheel travel is 300mm (11.8").
• Revised fork damping setting are optimized for cross country / enduro racing or riding
• Front fork adjustments include: 20-way compression damping and 20-way rebound damping. Optional fork springs are available through Genuine Yamaha parts.
• Large, "wrap-around" plastic fork protectors provide excellent protection from dirt, mud and stone chips. The "self-supporting" design reduces friction for smoother fork operation.
• Revised, Monocross link rear suspension features a fully adjustable, Kayaba, piggyback shock which provides 315mm (12.4") of wheel travel and features separate adjusters for high- and low-speed compression damping. Adjustments include: spring preload, 20-way rebound damping, 20-way low-speed compression damping and 2 turns of high speed compression damping. The damper rod is 18mm in diameter, while Kashima coating is used in the shock body and sub tank to reduce friction and improve suspension performance. The Kayaba shock utilizes a full rebound oil lock system for excellent suspension function and great ride quality.
• Revised shock damping setting are optimized for cross country / enduro racing or riding
• 250mm floating front disc brake with Nissin twin piston caliper features a "wave" style rotor (disc) which reduces weight and improves heat dissipation. Braking performance is excellent with great feel and control.
• "Shorty" style front brake lever is adjustable to fit various hand sizes.
• 245mm rear disc brake with wave style rotor and single piston caliper
• The rear brake caliper features a rugged plastic caliper protector, while the lower edge of the disc is protected by a lower disc guard.
• "Sun Star" rear sprocket increases the contact area between the sprocket and chain rollers, thereby reducing the load on the chain and increasing the service life of both chain and sprocket.
• New sealed O ring chain for excellent durability
• Lightweight, 21" front and 18" rear Excel rims provide exceptional durability and help reduce unsprung weight for optimal suspension performance and handling.
• Large, 8 litre plastic resin fuel tank features a new on - off - reserve fuel petcock for extra peace of mind. Reserve amount is approximately 2 litres.
• Aggressive, minimal body design provides a light weight feeling. The minimal design keeps the body looking good for an extended period of time.
• New lightweight aluminum side stand.

• "Flat-design" seat features multi density foam that provides good initial softness / comfort and then increases the firmness as more pressure is applied. The "pebble" finish on the top and side surfaces provides good rider grip and durability.
• Seat, handlebar and fuel tank ergonomics provide excellent freedom of movement for the rider.
• Lightweight YZ250F/450F based wide footpegs provide excellent grip and ground clearance.
• Rugged chain guide helps prevent the chain from de-railing and also helps to protect the rear sprocket.
• Serrated rear brake lever and folding shift lever tips offer superb grip and exceptional durability.
• Stainless steel, inner clutch cable provides excellent strength, smooth action and long life.
• Heavy-duty "O" ring chain.
• E10 friendly fuel system components