For 2015, the Kawasaki KX250F gets more adjustability.
New for 2015, the Kawasaki KX250F receives updates to its Showa SFF forks, new oversized Braking rotors, updated engine tuning, and adjustable footpegs and handlebar clamps.
Here is what Kawasaki has to say about its new KX250F:
NEW KX250F FEATURES FOR 2015
*Revised valves settings in the Showa Separate Function Fork (SFF)
*Revised Uni-Trak® rear shock settings
*Adjustable footpegs and handlebar clamps
*New 270mm “oversized” front rotor, petal-style Braking rotors front/rear
*New Downstream Fuel Injector and revised ECU settings
*New Bridged Box piston
*New Magneto Rotor with increased inertia
*Lighter subframe
*New Factory styling
The new KX250F features a new Downstream Fuel Injector and revised ECU settings.
ENGINE
The 249cc motor receives a new, reinforced Bridged Box piston borrowed directly from the factory race bikes. Like the KX450F, the light and strong Bridged Box piston design for the KX250F has short skirts with reinforced external ribs for increased strength. Added reinforcement for 2015 increased the weight of the new piston but a new piston pin was lighter than last year’s model, contributing strength and reliability without any weight penalty.
The exhaust system employs a short header and resonator chamber to enhance low-end power and provide strong top-end power. It also has a short, KX450F high-volume muffler that assists with mass centralization and makes good power, yet its large cross section restricts noise levels to an AMA race-legal 94dB.
Further engine improvements include a new magneto rotor with greater inertia to match the increased acceleration performance. The standard rotor now weighs 9.5kg-cm², which is up from 9kg-cm² on the 2014 model.
The combined effects of the engine’s improvements in both throttle response and power under-the-curve mean better drive out of the corners and more grunt for steep inclines.
ENGINE ELECTRONICS
The Digital Fuel Injection (DFI®) system on the KX250F utilizes dual injectors that deliver a second squirt of fuel under acceleration to maximize the engine’s power and over-rev capability at high RPM. Introduced in 2012, this second injector is located upstream in the air duct, helping to create a wider and more potent powerband.
The dual injectors are both fine-atomizing injectors with four holes. The upstream injector disperses particles with a droplet size of 120µm, while the downstream injector was reduced to 75µm for 2015. With a finer size and wider spray pattern, the downstream injector contributes to a stronger low- to mid-range power, along with improved response and quicker acceleration. These enhancements were also thanks to revised ECU settings to match the injector and magneto rotor changes.
The ECU has three pre-programmed ignition maps that allow riders to quickly and easily change DFI settings without needing to access a laptop or electronic device. So engine maps can be quickly switched between the three settings – Standard, Hard (terrain) or Soft (terrain) – to suit riding conditions. This is achieved by simply replacing the DFI coupler cap located on the side of the steering head. No additional tools or accessories are needed to change between pre-programmed maps – simply swap the appropriate DFI Coupler cap to select your desired ignition mode and feel an immediate change in power.
The ECU is also fully reprogrammable, allowing custom maps to be created using the accessory Kawasaki Racing Software Calibration Kit: the same tool used by Kawasaki factory and privateer teams in AMA and FIM racing.
Additionally, the KX250F retains the factory Launch Control mode that was the first of its kind for any 250 motocross bike when introduced last year. The system works by retarding the ignition in first and second gears, which allows the tire to find grip in low traction situations, helping the rider maximize traction and get a good start.
Launch Control mode is activated by simply pressing a button on the handlebar when in neutral, first or second gear. Shifting into third gear automatically deactivates the system to return ignition timing to the stock setting. This high-tech system is most effective on concrete starting pads or other slippery surfaces.
BRAKES & SUSPENSION
Both the KX250F and 450F get oversized front-brake rotors.
The new 270mm “oversized” front Braking rotor easily corrals the increased speed of the Kawasaki KX250F, giving the rider stronger performance and more control. For 2015, both the front and 240mm rear rotors are a new factory-style petal disc that look stylish and shed dirt more easily.
The high-friction brake pads grip the new rotors via a pushrod-type front master cylinder that helps ensure strong braking force. The front brake was tuned to be particularly effective on initial bite and in its mid-stroke action to provide enhanced feel and control.
The rear rotor is mounted to a rib-less rear hub with butted spokes that reduce the unsprung weight. The axles have also been reduced in weight, saving 31 grams on the front and 32 grams rear, with all these changes helping riders achieve even more podium finishes this season.
In 2011, the Kawasaki KX250F was the first production motocross bike to feature the Showa Separate Function Fork (SFF Type 2), and for 2015 its valve settings have again been revised to improve damping for high-speed handling and stability, keeping the Kawasaki in front of its competitors.
The 48mm SFF forks on the KX250F separate the damping and bump absorption duties into the individual fork tubes. The right fork leg houses the spring, which is easy to adjust, while the left fork leg contains the damping components that achieve the best small- and large bump absorption in its segment. The SFF assembly also means there is room for the preload adjuster. This significantly simplifies the task of setting the fork preload and front-end height. So rather than disassemble the forks, as you would need to do with conventional forks, Kawasaki’s SFF system means front and rear preload and height can be set with the simple turn of a wrench.
Furthermore, the large fork tubes allow 30mm main- and 35mm sub-pistons that provide a smoother action and firm damping performance at lower internal pressure.
The Showa forks have a super-hard titanium coating on the inner fork tubes to prevent abrasion, just like the Kawasaki factory team bikes. This reduces sliding friction and initial stiction to improve overall fork action. Green anodized caps and a new silver finish on the outer fork tube compliments the package and adds Works-racer style.
Rear suspension duties are assigned to the Uni-Trak linkage and a Showa shock has firmer settings to match the front fork upgrades, providing the same high-speed handling and stability. The shock features high- and low-speed compression damping adjustment and there is also a self-lubricating alumite coating on the inner surface of the shock cylinder wall to avoid abrasion, reduce friction and smooth the suspension action. These features help increase rear-wheel traction and power transfer to the ground.
FRAME & BODYWORK
Adjustable footpegs and handlebar mounts are now found on the KX250F.
Continuing with the Kawasaki KX250F refinements, the slim aluminium perimeter frame receives the new lightweight subframe previously found on the KX450F for improved mass centralization. The frame features narrow main spars that give the rider better control and allow for greater movement in the saddle.
As an industry first for the 250 class, the increased adjustability of the KX250F extends to new, two-position, adjustable footpeg brackets that allow the rider to lower the position by 5mm, thereby lowering the center of gravity.
Like its big brother, the KX250F also has a new four-position upper triple clamp with two sets of handlebar mount slots. These offer the rider the choice of four bar positions, including 25mm forward, 15mm forward, standard or 10mm back. The result is the ultimate ergonomic adjustment for riders of many sizes and styles. When combined with the almost limitless ignition mapping capabilities, thanks to the optional KX FI Calibration Kit, the Kawasaki KX250F is uniquely able to adapt to almost any track, any surface conditions and any rider.
The KX250F also shares the enhanced factory styling of its 450F brethren, thanks to factory-style graphics and, new for 2015 are green anodized suspension adjusters, engine oil cap and generator cover plugs. Along with the black alumite-coated wheels, the KX250F has the distinctive Kawasaki look.
Owners will also appreciate embossed design on the clutch cover, which was designed to gradually reveal itself as contact from the rider’s boots gradually wears away the painted surface.
From its styling to the race-proven performance, all aspects of the 2015 Kawasaki KX250F have been addressed to increase its outright ability while also making it more accessible than ever. So whether you’re a weekend racer, or a track rider looking for a lightweight and capable mount, the 2015 KX250F has the ability to continue its reign over the 250F class.
2015 KX250F
TEAM GREEN SUPPORT PROGRAMS
With the introduction of another highly capable motorcycle, Kawasaki will continue to offer the same support to racers of all ages and levels that it has for more than 30 years. The Team Green support program has given riders the tools for success by providing technicians and support staff at selected events throughout the year. Team Green provides racers with unparalleled trackside support at no cost, while emergency parts are for sale for last-minute adjustments. When helping amateur athletes achieve success, Kawasaki never forgets its most important goal is to ensure a positive and enjoyable experience for every rider, while giving them the chance to win the race! For more information about Team Green, visit http://www.kawasaki.com/Racing_TeamGreen/Landing.aspx
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