- Kawasaki KX250
The KX 250 is a two-stroke dirt bike. It has been ridden to several AMA Motocross wins, including a number of titles.
Change Log
1998
1999
Liquid Cooled Engine with Kawasaki Integrated Power Valve System
* KIPS system controls exhaust port height for increased power and torque
* Increased flywheel effect helps the rear tire hook up
* The output shaft now has involute splines at the countershaft sprocket for less play, quicker acceleration and increased durabilityKeihin Power Jet PWK38S Carburetor with K-TRIC
* New "shorty" design places the mainjet closer to the cylinder for improved throttle response
* Kawasaki Throttle Responsive Ignition Control (K-TRIC) uses a sensor and alter ignition timing according to throttle position and engine speed for better throttle response and more power
* Power jet system uses an electronic solenoid to close a fuel passageway at high rpm to extend the power peak and increase top-end power at over-revAirbox and boot
* New airbox and stiffer connecting boot improve airflow around the shock to improve top-end power
UNI-TRAK Rear Suspension
* Cast aluminum section is redesigned for less unsprung weight and more rigidity
* Redesigned needle bearings and sleeves reduce unsprung weight and prevent incorrect assembly that can cause them to bind
* The shock now features both low- and high-speed compression damping adjustments
* The shock oil seal head assembly and adjuster cap changed to aluminum and the aluminum shock clevis is now lighter to reduce unsprung weight
* New triple-rate shock spring improves suspension action at full compression46 mm Upside Down Cartridge Fork
* New aluminum upper fork tubes are smaller in diameter at the upper clamping area (54 mm to 52 mm) for a plusher ride and less weight
* Stronger inner and outer fork tubes have more overlap to improve suspension action, especially on "slap-down" landings
* New rubber bottoming damper and 10 mm longer fork bottoming cone reduce bottoming
* New fork leg lowers with two-bolt axle clamps increase front end rigidity
* Several internal components changed to aluminumFront and Rear Disc Brakes
* New ceramic coating on backing of rear brake pads insulate them from heat
* Backing plates now thicker to prevent warping under extreme conditionsHigh Tensile Steel Perimeter Frame
* Upper frame rails lowered slightly to lower fuel tank and provide flatter seating position
* New aluminum rear sub-frameDetail Changes
* New graphics and restyled rear fender and radiator shrouds
* Flatter seat allows freer rider movement
* New handgrips offer better feel
* Rerouted clutch cable for easier pull
by: naudia vengeace from commerce texas2000
Liquid Cooled Engine with Kawasaki Integrated Power Valve System
* Revised porting for increased low-end and mid-range power
* Revised KIPS system controls exhaust port height for increased power and torque
* KIPS governor bearing size is larger for increased durabilityElectrofusion cylinder
* Improves heat transfer for consistent power output
* It is porous so it holds lubrication well
* It is hard so it resists abrasion and seizure
* Allows closer piston-to-cylinder clearances for more powerKeihin Power Jet PWK38S Carburetor with K-TRIC
* "Shorty" design places the mainjet and slide closer to the cylinder for improved throttle response
* Kawasaki Throttle Responsive Ignition Control (K-TRIC) uses a sensor and alter ignition timing according to throttle position and engine speed for better throttle response and more power
* Revised Power Jet system uses an electronic solenoid to close a fuel passageway at two separate rpm settings to extend the power peak and increase top-end power at over-revUNI-TRAK Rear Suspension
* Cast aluminum section is redesigned for less unsprung weight and more rigidity
* The shock now features both low- and high-speed compression damping adjustments
* Aluminum shock components reduce unsprung weight
* Triple-rate shock spring makes shock action even more progressive46 mm Upside Down Cartridge Fork
* New bladder system helps smooth out jolts and control bottoming
* New .43 kg/mm fork springs
* Polished internal surfaces for smooth action
* New piston assembly on the cartridge is speed sensitiveFront and Rear Disc Brakes
* Redesigned front brake caliper for better feel
* Improved dust seals at the rear brake lever and caliperHigh Tensile Steel Perimeter Frame
* Compact and quick handling
* Removable aluminum rear sub-frame for easy access to the rear shockDetail Changes
* New graphics
* Flat seat allows free rider movement
* New handlebar bend for increased rider comfort2001
2002
Higher Compression Ratio
2003
Fuel Mix, from 30:1, to 40:1 or 52.5:1
2004
2005
Even Suspension Layout
Larger Fuel Tank
Larger Radiator
Internal Spark Arrestor
Oppositional Combustion Chamber Layout
Third Gear Ratio Moved Up 0.012 Degrees
Combustion Rate Improved
Leading Fuel Line Made 2mm Wider for Enhanced Riding Capabilities
Angled Piston Improves Horsepower by 2HP
Riding Position Lowered for Easy Handling
King Hart Racing Chain is Stock
Wobbling at High Speeds is Reduced By Carefully Shaped Air-Intake Ports
An Extra large aftermarket Spark Plug is Stock
Spark Arrestor 1.2mm Wider
Heat Proof Radiator Tubes Increase Performance
Entire Exhaust System polished on inside for Lower fuel consumption
Radiator Capacity has Increased From 800mls to 1030mls.
Evolved Piston head shape Increases displacement by 4cc
0.25 Litre Engine enhanced by stronger fuel Jets
8 Litre Fuel tank is increased to 8.5 Litres
2006
Renthal aluminum handlebars.
New piston profile and muffler design.
New reed valve stopper to improve low-rpm response
New water-pump impeller
Petal-shaped brake discs
New rear shock w/dual compression adjustability
Kayaba AOS (Air-Oil-Separate) fork w/one-piece TCV sleeve
New graphics and seat cover
Wikimedia Foundation. 2010.
