Description
Conquer Dirt
Revive memories of the good ol' days with a YZ two-stroke! Nothing beats the "bark," and instantaneous throttle response of the lightweight YZ250. Not only is a 2-stroke more affordable and easier to maintain, they also provide a very entertaining ride. |
Power
Liquid-cooled, 249cc, piston-reed-valve-inducted, 2-stroke engine is lightweight and compact. |
Performance
The Yamaha Power Valve System (YPVS) features a total of three slides (one main and two auxiliary slides) which provides the benefits of both solid, low rpm power delivery and a strong top-end punch. The YPVS system varies the exhaust port height and timing based on engine rpm. |
Features & Benefits
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Key features
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Compact, liquid-cooled, 249cc, piston-reed-valve-inducted, 2-stroke engine
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Smooth shifting, 6-speed, close ratio transmission
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Keihin PWK38S carb with 4-petal carbon fiber reeds
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Yamaha's patented YPVS exhaust power valve system
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Lightweight, aluminum, semi-double-cradle frame with detachable rear subframe
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Fully adjustable KYB suspension
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270 mm front & 245 mm rear disc brakes
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Adjustable aluminum handlebar & titanium foot pegs
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Aggressive, modern styling
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ENGINE
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Lightweight, compact, liquid-cooled, 249cc, piston-reed-valve-inducted, 2-stroke.
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super crisp, instant 'right now' engine power (when in the 'power band')
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easy & economical to maintain, service & rebuild
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Lightweight, flat top forged aluminum piston.
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excellent durability
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light weight means fast engine response
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Liner-less, ceramic composite cylinder bore with ceramic coating sprayed directly on the aluminum block.
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excellent heat dissipation
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reduced weight (no heavy iron liner)
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reduced friction
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extended cylinder life
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Lightweight, ball bearing style crank.
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lightweight design for fast throttle response
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friction reducing crank seals
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YPVS power valve system features a total of three slides (one main and two auxiliary slides).
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YPVS system varies the exhaust port height & timing based on engine rpm
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provides the benefits of both solid, low rpm power delivery & strong top-end punch
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Keihin PWK38S carburetor with power jet and throttle position sensor (TPS).
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precise fuel - air mixing
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extra-crisp throttle response throughout the powerband
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Special-design, 4-petal, carbon fiber reeds.
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excellent throttle response & engine performance across the entire RPM range
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Smooth-shifting, 5-speed, close-ratio transmission.
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ratios are matched to engine output for maximum performance
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optimal hook-up for outstanding acceleration & corner-exiting power
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transmission features 'involute splines' for smooth, positive shifting even under power
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Heavy-duty, multi-plate clutch.
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quick-access, outer clutch cover allows for fast, easy clutch maintenance
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CD (capacitor discharge) ignition system.
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delivers a precise spark for fast, sure starts
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ensures optimal timing at all rpms for fast, strong response.
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High capacity, washable, dual-stage, foam air filter.
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excellent filtering qualities
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reduces maintenance costs... foam filter is re-useable
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Large-capacity, dual radiators feature 10-row cores.
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maximum cooling efficiency
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Lightweight exhaust system.
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computer designed expansion chamber provides maximum engine performance
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lightweight, aluminum silencer is re-buildable for optimum performance & reduced noise levels
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Works-style clutch lever & race-spec 'barrel adjuster.'
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light, easy lever pull
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for on-the-fly clutch adjustments
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CHASSIS/SUSPENSION
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Lightweight, aluminum, semi-double-cradle frame.
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combines with compact engine to provide an awesome power to weight ratio
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obvious benefit of an aluminum frame is a significant weight reduction
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Yamaha maintains the semi-double cradle design because it offers an excellent 'rigidity balance' between lateral & torsional rigidity while offering controlled flex in the longitudinal plane
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result is a light aluminum frame, which provides excellent handling, good ride quality, excellent stability & responsive cornering performance
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Removable rear subframe.
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constructed of square-section, lightweight aluminum
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detachable design allows easy access when servicing rear suspension components
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reduces costs in the event of a loop out
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Lightweight, tapered design aluminum swingarm.
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produced by 'hydro forming', a forming method that uses high pressure water to form shapes
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excellent rear wheel traction & control
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lightweight design
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Cast aluminum upper and forged lower triple clamps.
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strong yet lightweight
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fast, agile handling
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Adjustable handlebar mounts.
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allow handlebar to be moved 10mm rearward if desired
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'Speed Sensitive System' 48mm, adjustable, inverted, 'twin chamber' KYB fork. Front wheel travel is 300mm (11.8').
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twin chamber design means the damper unit is in a separate structure which prevents aerated fork oil from entering the inner damper assembly & degrading its damping abilities
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the inner damper is pressurized, it also eliminates bubbles forming in the oil
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'Speed Sensitive' design means the damping force is controlled by piston speed, not position in the fork
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low friction fork seals provide reduced stiction for a smoother stroke
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fork adjustments include: 20-way compression damping & 20-way rebound damping
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optional fork springs are available through Genuine Yamaha parts
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Fork also features a Transfer Control Valve (TCV).
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TCV enhances damping from mid to full stroke & improves bottoming characteristics
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TCV offers more precise control throughout the full suspension stroke
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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'
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Large 'wrap-around' plastic fork protectors.
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provide excellent protection from dirt, mud & stone chips
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'self-supporting' design reduces friction for smoother stroke
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Monocross link rear suspension features a fully adjustable, Kayaba, piggyback shock which provides 315mm (12.4') of wheel travel.
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features separate adjusters for high- and low-speed compression damping
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adjustments include: spring preload, 20-way rebound damping, 20-way low-speed compression damping & 2 turns of high speed compression damping
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damper rod is 18 mm in diameter
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Kashima coating (friction reducer) is used in the shock body & sub tank to reduce friction & improve suspension performance
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piggyback shock utilizes a full rebound oil lock system for excellent suspension function & great ride quality
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270 mm floating front 'wave-style' disc brake with Nissin twin piston caliper.
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'wave' style rotor (disc) reduces weight, improves cooling (more surface area) & improves styling
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braking performance is excellent with great feel & control
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'Shorty' front brake lever is adjustable for various hand sizes.
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245 mm rear 'wave-style' disc brake with single piston caliper.
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integrated master cylinder (fluid reservoir is integrated into the top of the master cylinder)
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'wave' style rotor (disc) reduces weight, improves cooling (more surface area) & improves styling
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strong stopping power with excellent feel & control
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Rugged, plastic rear caliper & lower rear disc protectors / guards.
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Lightweight, Sun Star rear sprocket.
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increases the contact area between the sprocket & chain rollers
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reduces the load on the chain & increases service life of chain & sprocket
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Lightweight, D.I.D. 21' front and 19' rear rims & premium Dunlop tires.
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provide excellent durability
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reduces unsprung weight for optimal suspension performance & handling
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'Flat-design' seat features multi density foam.
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provides good initial softness / comfort and then increases the firmness as more pressure is applied
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'pebble' finish on the top and side surfaces provides excellent rider grip & durability
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Seat, handlebar & fuel tank ergonomics provide excellent freedom of movement for the rider.
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Details
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Slim design, modern aggressive bodywork allows easy rider movements
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Lightweight YZ250F/450F based wide footpegs provide excellent grip & ground clearance
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Rugged chain guide helps prevent the chain from de-railing and also helps to protect the rear sprocket.
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Serrated rear brake lever and folding shift lever tip
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Stainless steel, inner clutch cable provides excellent strength, smooth action and long life
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Heavy-duty chain
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E10 friendly fuel system components
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