2010 Kawasaki KX™250F

Additional Features

• Large front brake lever boot offers increased protection against debris
• New chain with thinner inner links provices 20 g in weight savings
• Large resin skid plate offers great protection with minimum weight
• Slim and compact 34 mm wide chain guide, utilizes a thick wear pad for longer life

Enhanced Durability and Reliability

• Big-end bearing widened from 18 to 19 mm; it features a thicker copper plating on its cage and a longer crank pin for increased reliability
• Revised oil pump rotors offer increased reliability and durability; a larger feed pump rotor size increases oil flow, while a smaller scavenge pump rotor reduces mechanical loss
• Electrofusion treatment on cylinder bore improves surface oil retention and the molybdenum coating on the cylinder bore surface helps resist scorching, further contributing to durability

Factory-style Components

• New thicker and more rigid front fender
• Rear caliper guard protects the caliper from damage
• Revised rear brake pad material offers stronger braking performance
• Ribless rear hub and butted spokes further reduce unsprung weight
• Renthal aluminum handlebar is standard equipment
• Rims are coated in Black alumite - just like the factory racers
• Factory-style graphics complement the KX250F's highly tuned performance and black plastic covers, triple clamps, number plates, and engine covers
• Front and rear petal disc brakes help reduce unsprung weight, and the wave shape helps clean the brake pads for more efficient braking performance
• New rim design with revised cross section offers both increased strength and lighter weight

Higher Performing, High-revving Engine

• Crank web design increases offsetting moment for a high crankshaft balance factor with the balance factor on par with the factory racers; resulting in reduced engine vibration, smoother power delivery and increased performance in the mid-high rpm range
• 249 cc, liquid-cooled, four-stroke, four-valve, single-cylinder DOHC engine delivers hard-hitting power from mid- to high-rpm
• Hot start system permits quick starting when the engine is hot; the hot start lever is unitized within the clutch lever assembly, reducing handlebar clutter
• Sprocket-style chain drive roller helps reduce the effect of driveline lash and engine braking for smoother and faster corner entries
• Race-experienced riders will be able to harness its high-rpm performance that extends way into the over-rev
• Engine tuned to achieve the widest possible torque band, so that traction efficiency is maximized through a greater percentage of the rev range

Increased Shifting Reliability

• Sub-frame is 1.3 pounds lighter via larger diameter tubing with thinner walls, yet still provides a secure mounting for the new silencer
• New design is 2.2 pounds lighter than previous model
• Swingarm pivot is located higher in the frame for improved rear wheel traction
• Frame has a new 6 mm slimmer overall width main spars shape, narrowing near the bend below the seat for a riding position then widening at the ankles to offer better grip
• Weight savings and rigidity balance aided by down tube with a smaller cast bracket that's now formed via a swaging (squeezing and hammering) process
• Rigidity increased by moving upper engine mounts to sides of the head cover
• Newly designed main, lower and gusset pieces around the fuel tank with revised cross sections

Lightweight and Effficient Top End

• Intake ports designed for peak performance at all rpm, especially in the high-rpm range
• The ultra-light valves have extremely thin valve stems on par with those found in supersport machines with the intake valves featuring thicker heads for increased strength
• Special coating applied to the intake port cores during the casting process gives the intake ports extremely smooth surfaces and optimum intake efficiency across the rev range
• Silicon coated head gasket provides excellent sealing
• Lightweight, highly rigid, titanium 31 mm intake and 25 mm exhaust valves reduce reciprocating weight and offer greater high-rpm reliability
• Cam chain tensioner spring reduces mechanical loss by approximately 30 percent
• Increased auto-decompressor spring preload on the exhaust cam for easier starting

New Piston

• New lighter, stronger piston shares the same design as the factory racers, with a revised profile with a shorter skirt, reinforced external ribs and the first mass-production use of a bridged-box bottom, featuring fully flush internal bracing
• Through a revised piston crown, combustion is improved and cylinder height was increased accordingly to maintain compression ratio at 13:2:1
• Shorter piston pin reduces reciprocating weight

New Stainless Steel Exhaust Pipe

• Silencer meets 99 dB AMA noise regulations
• Longer head and shorter mid secton on the tapered exhaust pipe for increased low-rpm performance
• Revised joint between the exhaust pipe and muffler for improved sealing and increased durability gained by using a rubber damper collar on the rear silencer mount
• New stainless steel construction features a revised shape and extra durability

Quick-turning Chassis

• Upper engine mounts on sides of the head cover, increasing rigidity
• The KX250F's slim and lightweight aluminum perimeter frame construction is composed of forged, extruded and cast parts
• Utilizes a new steering stem with lower rigidity for lighter handling
• Center of gravity and key dimensions such as swingarm pivot, output sprocket and rear axle locations designed to increase forward drive with minimal rear-end squat

Race-oriented Suspension

• Revised race-oriented suspension settings optimized front / rear balance, resulting in a flatter (less forward-leaning) chassis posture when riding
• Revised shock damping settings offer increase absorption performance and greater stability on corner entry thanks to reduced rear-end kicking
• Showa twin-chamber fork keeps oil and air in separate chambers for stable damping performance during long motos
• Features Kashima Coat on tank cylinder for reduced friction and smoother suspension action
• Further, revised damping settings and a less rigid steering stem offer improved action (smoother) and increased absorption performance
• Wrap-around Black fork tube guards provide greater protection for the inner tubes
• Super-hard titanium coating on the outer surface of the inner fork tubes reduces stiction and improves suspension action; the increased surface hardness of the Dark Navy Blue coating also helps prevent scratches and damage to the tubes
• Rear shock features dual compression adjustability, allowing high-speed and low-speed damping to be tuned separately
• Friction-reducing Kashima Coat on the inside of the outer fork tubes contributes to smoother suspension action, especially during the inital part of the stroke

Race-oriented Suspension Overview

• First mass production or a high performance piston featuring a bridged-box bottom
• Chassis balance and suspension settings aimed at race-experienced riders
• Quicker-turning chassis
• Durable stainless steel exhaust
• Increased engine performance and durability

Rider Interface

• Clutch cable boot features a large quick adjuster, making it easy for riders to adjust play in the clutch cable while on the fly
• Slim seat geatures firmer urethane which keeps its original shape longer
• Right side panel has an added passageway to aid in cooling the silencer
• Frame is wider at the ankles to offer better grip and narrows near the bend below the seat to allow a slim riding position
• Designed with rider ergonomics in mind, bodywork components offer the rider a slim interface, the natural position making it even easier for racers to go fast
• Side number plates also two-toned and contribute to the slim package
• 50 mm wide (front-to-rear) footpegs designed to offer grip and superb feel at the pegs
• Lightweight short-length grips feature a pattern designed to provide excellent grip
• Seat has a slip-resistant top surface for good grip when seated and smooth sides for excellent rider mobility
• Throttle grip has a one-piece collar that provides additional stability during throttle operation
• Formed using a double-injection molding process, the two-tone shrouds were fine-tuned to accommodate the new radiators, and feature a slightly slimmer design

Stronger Cooling

• Cylinder head water jacket routes coolant via the front of the cylinder head for even cooling
• New 10 mm thicker and 4 mm wider radiators have increased fin and tube pitch, are stronger, offer improved resistance to mud build-up and provide better cooling performance
• The stronger radiators mean the reinforcing brackets could be eliminated and overall weight reduced

Superior Rear-wheel Traction

• Swingarm features a revised cross-section, wall thickness and internal ribs for improved cornering performance, enabling lighter turn-in and tighter cornering
• Revised linkage ratios for the new Uni-Trak rear suspension to match new rear shock damping settings to achieve maximum rear wheel traction
• Alloy swingarm uses a cast front section, tapered hydroformed spars and forged chanin adjusters
• Uni-Trak® rear suspension system mounts the suspension arm below the swingarm, allowing a longer rear suspension stroke and more precise tuning