2015 Yamaha YZ 250 F
JUST ARRIVED - IN THE SHOWROOM
YAMAHA'S BEST SELLING SET UP! YZ250F, POWERFUL 250CC FOUR-STROKE EFI ENGINE, READY TO HIT THE TRACK!
SOME LIGHT SCUFFS ON PLASTICS
The fuel injected 2015 YZ250F offers excellent power and amazing cornering performance thanks to exhaustive mass centralization efforts and a compact chassis design. Balancing the three essential elements of an ultimate motocrosser: easy cornering, lightweight & compactness and a deep, useable power band, the YZ250F has the response and depth of power that the competition can't match!
Power: "Reversed" liquid-cooled, 250cc, DOHC, 4-valve (titanium), 4-stroke, single with fuel injection. The engine has been tuned for excellent "drivability and controllability" and delivers a broad, easy to use power band with excellent power characteristics in the mid to upper rpm range.
Performance: Innovative circular exhaust system. The header pipe exits from the rear of the engine and then winds its way around the cylinder body before turning to the rear of the bike. This design ensures the correct tuned header length, maximizes the exhaust pulse effect and centralizes mass by moving weight closer to the centre line of the bike.
Frame: Compact "Bilateral Beam" aluminum frame centralizes mass for exceptional handling. The benefit of this frame is reduced weight, optimum rigidity balance and excellent mass centralization.
- Revised piston
- Revised shift cam stopper
- Revised return spring on throttle body
- New ECU settings
- New quick release fasteners on the air box cover
- Optimized fork settings
- Black Excel rims
- The design goals for the fuel injected YZ250F are a balance of easy cornering, lightweight and compact feeling thanks to excellent mass centralization. The fuel injected engine features a wide, controllable power band that sets the standard in the 250 class.
- "Reversed" liquid-cooled, 250cc, DOHC, 4-valve (titanium), 4-stroke, single with fuel injection. The engine has been tuned for excellent "drivability and controllability" and delivers a broad, easy to use power band with excellent power characteristics in the mid to upper rpm range.
- YZ450F based engine design features a rearward slanting cylinder that is "reversed" compared to traditional designs. The FI throttle body and air box are front mounted and provide a straight intake path, while the exhaust exits from the rear of the cylinder. This design is used to centralize mass for excellent handling and a light feel. The other major benefit is the straight shot intake system which maximizes power output.
- The "reversed" design allows for a straight intake path into the cylinder, providing maximum intake flow and efficiency for excellent power. The front positioned intake means that engine heat will have less "heating effect" on the incoming fuel charge (cooler fuel helps increase power). The most important benefit of this design is mass centralization which improves both handling and suspension performance.
- Compact 4-valve cylinder head features a 13.5:1 compression ratio. The intake valves are 31mm in diameter while the exhaust valves are 25mm, with a 23.75 degree valve angle for a compact combustion chamber design. The 4-valve design offers optimum flow and improved power.
- Lightweight titanium valves (intake & exhaust) and load-reduced oval valve springs reduce reciprocating mass for less friction, faster-revving and smoother-hitting power delivery across the rev range.
- Automatic cam chain tensioner reduces maintenance while special cam chain "sliders" reduce internal frictional losses.
- High performance, light weight hollow intake and exhaust camshafts enhance this unique engine design and offer broad power especially in the mid to high rpm range.
- The lightweight aluminum cylinder features a ceramic composite coating applied directly to the aluminum block, eliminating the need for a liner or sleeve. The ceramic coating insures faster, more uniform heat dissipation, reduced friction and a longer service life.
- Special cylinder design features cutaways that allow the air "trapped" under the piston to enter a side chamber (or cutaway) to reduce horsepower-robbing "pumping losses."
- The crankcase also utilizes cutaways to reduce "pumping losses". The crankcase cutaways match the cutaways in the cylinder for maximum efficiency.
- Revised lightweight, short-skirt, forged aluminum piston features a single compression ring and a special designed oil control ring design that increases the surface contact area for better sealing. This 2-ring design benefits include decreased sliding resistance, reduced weight and improved horsepower.
- Piston oil cooler utilizes a pinpoint nozzle that directs oil to the desired portion of the cylinder and underside of the piston, which reduces piston, cylinder and rod temperatures for great durability.
- Lightweight gear driven counterbalancer shaft reduces vibration for improved rider comfort and less rider fatigue.
- The crankcase features a tri-axis layout for the crank, main and drive axles. This tri-axis design keeps the crankcase more compact while also centralizing mass for excellent handling. All of the shafts are positioned low in the cases to maintain a low centre of gravity.
- Revised 5-speed transmission utilizes a 2-bar shift guide system, a revised shift cam stopper lever and a 14mm shift shaft. The benefit is smooth, positive shifts and good durability in the event of a crash. Overall, the transmission is well matched to engine output and reduces "driving force" losses.
- Heavy duty multi-plate (wet) clutch.
- Quick-access, lightweight magnesium outer clutch cover for fast, easy clutch maintenance.
- 44mm Keihin throttle body fuel injection system is a battery-less design. The 10-hole injector and 16 degree spray pattern maximizes fuel atomization for more complete combustion and excellent power delivery. The benefits of fuel injection include constant ongoing adjustments to insure the optimum fuel - air ratio regardless of outside air temperature and altitude. Other benefits include improved starting and improved throttle response. There is also a cold start knob which also doubles as an idle adjuster too.
- Revised return spring on throttle body for less fatigue during long motos or extended riding periods.
- The injector spray pattern, spray direction and the distance to the intake valves have been optimized, while the specially designed straight intake tract helps to maximize the benefits of the FI system and overall power output.
- New ECU settings for both ignition timing and the FI system settings.
- Optional, compact, hand held "YZ Power Tuner" allows tailoring of both fuel injection settings and ignition mapping. Nine (9) different setting points can be accessed for both the FI map and the ignition map. Maps can be stored and shared with other Power Tuners if desired.
- Forward mounted air box features a flat style, washable, dual-stage, foam air filter which is easily accessible without removing the tank or seat. New quick release, no tools required, fasteners on the air box cover for faster servicing.
- Wet sump lubrication system reduces weight, allows for more compact engine cases and eases maintenance.
- Oil volume in the engine has been optimized to reduce weight and oil drag related power losses.
- Compact, lightweight in-tank electric fuel pump.
- Maintenance-free transistor-controlled digital ignition (TCI) ensures fast starts and great performance at all rpms.
- High capacity ACM (alternating current magneto) is used to eliminate the need for a battery.
- Automatic decompression system ensures easy starts in any gear.
- Wrap-around exhaust system exits from the rear of the engine and circles around the cylinder body before turning to the rear of the bike. This design ensures the optimum tuned header length, maximizes the exhaust "pulse effect" and centralizes mass by moving weight closer to the centre line of the bike.
- Re-packable lightweight aluminum / stainless steel muffler (aka silencer) sound output is 94dba to meet the current AMA and CMRC sound regulations.
- Compact, lightweight, single core, dual radiators provide outstanding cooling efficiency.
- Special "G" sensor system will shut down the fuel injection system if the bike lies on its side for more than 10 seconds to help prevent costly engine damage. There is no special procedure to re-start the bike... just kick it and go.
- Works-style race-spec "barrel adjuster" for on-the-fly clutch lever free play adjustments.
- Easy access oil filter.
- Compact, lightweight "Bilateral Beam" aluminum frame centralizes mass for exceptional handling. The frame is made up of forged, cast and extruded aluminum parts providing outstanding strength, an optimum rigidity balance and shock absorbing qualities that contribute to exceptional cornering. This frame is compact and offers excellent "rider - machine communication" (a.k.a. feedback). The engineers have optimized the balance between strength, rigidity and flex. The key goal of the chassis is faster and easier cornering ... one of the main keys to winning races.
- Lightweight, tapered aluminum swingarm is produced using "hydro forming", a special method that uses high pressure liquid to form shapes. The chain puller notches have been revised for ease of use.
- Lightweight detachable rear sub frame is constructed of square-section, lightweight aluminum pipe with no bends. The detachable design allows easy access when servicing rear suspension components.
- Cast aluminum upper triple clamp. The handle bar clamps are rubber mounted for improved rider comfort.
- Adjustable handlebar clamps offer a total of 4 different handlebar positions with an adjustment range of 30mm, to suit a wide variety of riders.
- 48mm, adjustable, inverted, Kayaba cartridge fork offers 310mm (12.2") of wheel travel. Inner tubes feature a special surface treatment for smooth performance. Settings have been optimized for '15. Front fork adjustments include: 20-way compression damping and 20-way rebound damping. Optional fork springs are available through Genuine Yamaha parts.
- The fork features a twin-chamber, "Speed Sensitive System" design meaning the damper unit is in a separate structure which prevents aerated fork oil from entering the inner damper assembly and reducing its damping abilities. Since the inner damper is pressurized, it also eliminates bubbles forming in the oil.
- The 48mm inverted KYB fork also features a Transfer Control Valve (TCV). The TCV enhances the damping force from mid to full stroke and improves bottoming characteristics. The benefit of TCV is more precise control throughout the full suspension stroke. The 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. The "self-supporting" design reduces friction for smoother fork operation.
- Monocross link rear suspension system features a fully adjustable, large capacity, Kayaba piggyback shock which provides 315mm (12.4") of wheel travel and features separate adjusters for high- and low-speed compression damping. The shock is in-line with the center axis of the bike for excellent control. Shock adjustments include: spring preload, 30-way rebound damping, 20-way low-speed compression damping and 2 turns of high speed compression damping.
- 250mm floating front "wave-style" disc reduces weight, improves cooling and adds style too. The disc is squeezed by a compact Nissin twin piston caliper fitted with lightweight aluminum pistons.
- "Shorty style" adjustable front brake lever can be adjusted to fit various hand sizes.
- 245mm rear disc brake features a "wave-style" disc. The rear disc is squeezed by a single piston compact Nissin caliper.
- Lightweight, compact, integrated Nissin rear master cylinder (fluid reservoir is integrated into the top of the master cylinder) provides strong stopping power with excellent feel and control.
- The rear caliper and the lower portion of the wave style disc are protected by heavy duty plastic protectors.
- Lightweight, plastic resin 7.5 litre fuel tank is located under the seat, once again reducing the centre of gravity and centralizing mass for exceptional handling performance. The fuel tank is able to flip backwards 180 degrees (flip onto its back) without disconnecting the fuel line for easier servicing under the tank.
- Compact body work reduces weight and enhances the lightweight feel and look of the YZ250F. This "minimal design" bodywork is a flat design, allowing for fast, easy rider movements and provides a natural and roomy riding position. Minimal design aids in keeping the body looking good throughout the life of the machine.
- Graphics are impregnated directly into the plastic rad shrouds. They will not peel off or get damaged by pressure washing.
- The seat design is flat for easy rider movements and features a "cap cover" to access the fuel cap. There is no fuel cap visible with this design. The fuel filler "cap cover" snaps into place, via grommets. The non-slip seat cover material resists clogging with dirt or mud to ensure long lasting good looks.
- Rugged, 21" front and 19" rear black Excel rims provide exceptional durability and help reduce unsprung weight for optimal suspension performance and handling.
- 22mm front axle increases overall front end rigidity.
- Large 25mm rear axle and a hub design which features a second bearing on the sprocket side for increased rigidity and durability.
- Clutch cable features integrated silicone grease in the cable and a Teflon liner for smooth cable operation.
- Convenient oil level sight glass window
- Lightweight, extra wide foot pegs provide excellent grip and ground clearance.
- Folding shift lever tip helps prevent damage.
- Lightweight chain guide / support helps reduce chance of chain derailment and also helps protect the rear sprocket.
- Heavy duty rubber swingarm protector
- Heavy duty DID 520 drive chain
- Easy access Power Tuner and Yamaha Diagnostic tool connectors
- E10 friendly fuel system components
- Engine: 4-stroke, liquid-cooled, DOHC, 4-valve (titanium), single
- Displacement: 250cc
- Bore and Stroke: 77 x 53.6 mm
- Compression Ratio: 13.5:1
- Fuel Delivery: 44 mm Keihin throttle body F.I.
- Lubrication: Wet sump
- Ignition / Starting: TCI / Kick
- Transmission: 5-speed
- Final Drive: Chain
- Suspension (Front): Adj. 48 mm, inverted fork / 310 mm (12.2 in.) travel
- Suspension (Rear): Fully adj. Monocross / 315 mm (12.4 in.) travel
- Brakes (Front): 250 mm, floating disc / twin piston caliper
- Brakes (Rear): 245 mm disc / single piston caliper
- Tires (Front): 80/100-21
- Tires (Rear): 100/90-19
- Length: 2,165 mm (85.2 in.)
- Width: 825 mm (32.5 in.)
- Height: 1,280 mm (50.4 in.)
- Wheelbase: 1,475 mm (58.1 in.)
- Ground Clearance: 325 mm (12.8 in.)
- Seat Height: 965 mm (38 in.)
- Fuel Capacity: 7.5 L (1.7 imp. gal.)
- Wet Weight: 105 kg (231 lb.)
- Colour(s): Purplish White
- Engine Type
- 4-stroke, DOHC, 4-valve (titanium), single
- Bore and Stroke
- 77 x 53.6 mm
- Compression Ratio
- Fuel System
- 44 mm Keihin throttle body F.I.
- Front Suspension
- Adj. 48 mm, inverted fork / 310 mm (12.2 in.) travel
- Front Brakes
- 250 mm, floating disc / twin piston caliper
- Front Tire
- Rear Suspension
- Fully adj. Monocross / 315 mm (12.4 in.) travel
- Rear Brakes
- 245 mm disc / single piston caliper
- Rear Tire
- Dry Weight
- Curb Weight: 105 kg (231 lb.)
- Fuel Capacity
- 7.5 L (1.7 imp. gal.)
- 1,475 mm (58.1 in.)
- Ground Clearance
- 325 mm (12.8 in.)
- Seat Height
- 965 mm (38 in.)
- Final Drive
- Purplish White