Kawasaki’s KX250F has long been a top contender in the 250 class motocrossers since its release, with each year bringing new improvements to keep it at the top of the pack. A stout mix of race-bred suspensions and aggressive aerodynamics, the KX250F stands out on any track, whether pavement or dirt.
With its blazing speed, lightning-fast throttle response, knobby tires, and super-agile handling, there’s no denying this bike is up for any racecourse in the world. It’s no surprise that it has taken home more Supercross, and Pro Motocross wins than all other OEMs combined.
So what makes the KX250F different from all the other motocross bikes out there? Is it up to the task of putting the monster-truck feel on a bike? Let’s explore these questions and common queries that tag along as we review the KX250F going over its key specifications and features.
About Kawasaki KX250F
The Kawasaki KX250F is a motocross motorcycle produced by Kawasaki that belongs to its factory edition of the KX 250. The bike has been in production since 2004, and it is still rolling off the production lines to this day.
KX250F has undergone several revisions throughout its production history, each of which has been a favorite of off-road enthusiasts for years. The motorcycle made its public debut at the 2003 Tokyo Motorcycle Show. It was then launched in 2004 as a 2005 model, as one of several four-stroke motocross bikes released by the Japanese motorcycle manufacturers that year.
The Kawasaki KX250F was an immediate success in sales and racing results due to its astounding speed. It won the 2004 AMA Supercross Lites West championship with Ernesto Fonseca, followed by another Lites West title for Michael Byrne in 2005 and a 2006 AMA Motocross Lites championship for Ryan Villopoto.
This bike consistently receives high praise for its excellent handling among its many modern features, largely thanks to its frame geometry, which is incredibly rigid and lightweight due to its single backbone design and high-tensile steel. As such, it provides the rider with quick transitions through bumps and corners, which is rarely the case with many other motocross bikes today.
If you’re wondering what distinguishes it from KX 250, Kawasaki’s classic dirt bike, the main difference is its fuel injection system. The KX250F has a Keihin 44mm throttle body injection system, while the standard KX 250 has a Keihin 28mm carburetor. On the whole, the bikes are very similar.
Kawasaki KX250F Specs & Features:
Kawasaki’s KX250F has evolved through several versions since its debut, with each adding a few new features. Following is a breakdown of the KX 250’s key features for 2022.
The 2022 KX250F has a 4-stroke, DOHC, liquid-cooled, single-cylinder, 4-valve engine that produces a maximum power output of 39.5 hp. It employs Kawasaki’s KIPS technology, enabling variable intake port timing for increased power and torque. Its new cylinders and pistons have improved handling over last year’s model.
The KX250F’s Digital CDI ignition system is fully adjustable to suit any track conditions. You can adjust the ignition advance curve in three stages using optional parts. It’s also possible to fine-tune the ignition timing by moving the sensor on the crankcase.
The KX250F features a fuel injection system with dual injectors, with an injector, mounted in each throttle body. The second injector sits downstream, closing to the intake valve, and assists with atomizing the air/fuel mixture.
Injection “staging” delivers a precise fuel mixture for ultimate power. The DFI coupler connects the secondary injector to the ECU and allows for a “staged” fuel injection system. Its ECU can deliver a precise fuel mixture independent of engine rpm and throttle position using the two injectors.
Transmission and Drivetrain
The KX250F features a five-speed transmission and light-action, multi-disc wet clutch with a coil spring instead of the steel plate-spring used on most motocross machines. This design improves the feel and reduces engine stalls when idling.
An additional benefit is a slimmer clutch cover that contributes to the KX250F’s slim chassis profile. Two steel and six friction plates make up this cable-operated system for better heat dissipation. And it uses a 120-link, 520-pitch chain for its final drive.
The 250F features petal disc brakes front and rear, with 270mm discs at the front and a larger 240mm at the rear. You can expect greater braking power and a better brake feel with these discs.
Its semi-floating front disc brake features a lightweight, rigid dual-piston caliper with a radial-pump master cylinder. Also, the 250F features hydraulic clutch actuation.
KX250F’s front has a 48mm inverted telescopic coil-spring fork with 23-way compression damping and 20-way rebound damping. In contrast, the rear boasts New Uni-Trak with dual-range forks with 2.25 turns high-speed, compression damping, 38-way rebound damping, and adjustable preload.
Wheels and Tires
The KX250F wheels are lightweight and robust, with the smallest front hub in the series to date. Likewise, the rear one is compact and lighter, with the spokes changed from two to three-cross, unlike the previous year’s make.
Excel makes its aluminum alloy rims, which also makes hubs for Kawasaki’s racing team. It uses knobby Dunlop Geomax MX51 tires. The front tire size is 80/100-21 51M, and the rear tire size is 100/90-19 57M.
The Kawasaki KX 250 stands out among motocross bikes because of its 85.8 inches overall length. Its height from the bottom of the handlebars to the top is 49.8 inches. It stands 32.3 inches wide with a wheelbase of 1,485 mm.
The ground clearance is 13.2 inches, and the turning radius is 3.8 m. Its seat height is 37.4 inches, the dry weight is 226.4 lbs, and it can hold 1.64 gals of fuel.
The KX250F has an aluminum perimeter frame and swingarm tough enough to take a beating. Its cast aluminum rear has a reinforced steering head tube, tapered front edges, enlarged main spar, gusset-free cross members, and thickened central perimeter spars.
Cast aluminum makes up its rear subframe, coupling with the engine mount in the front, creating a single structure for optimal strength and rigidity.
KLCM (Kawasaki Launch Control Mode)
The KX250F is the first production motocross bike to feature Kawasaki’s KLCM (Kawasaki Launch Control Mode). The system offers riders the ability to set specific engine rpm ranges, allowing the rider to select a launch rpm within that range.
When the rider engages the clutch and releases it, the engine will maintain that rpm range and not rev past it until the clutch is released. Thus, riders can start more confidently since their rear tire will not spin as much.
Kawasaki KX250F Top Speed
The KX250F can reach top speeds of around 100 miles per hour. However, on average, this bike gets about 84-89 miles per hour when out on the track. It depends on how high the rider can rev the engine, which is, as of yet, unspecified. Additionally, there are factors like the rider’s weight, ability, experience, weather conditions, terrain, etc.
In terms of mechanical factors, the main one is the gearing ratio, which determines the number of times the back wheel turns for every tire turn. A lower gearing ratio will result in higher speeds; however, this will also decrease acceleration and power. Then comes torque, which increases the bike’s acceleration and maximum speed as it increases.
How to Increase the Kawasaki KX250F Top Speed?
With a top speed of 100 mph, the KX250F is already a racing monster. However, that speed can often be challenging to reach when in stock condition. That’s why many riders choose to modify their machines to achieve the optimal speed every time.
Here are some practical recommendations you can follow if you want to increase the top speed of your KX250F without sacrificing its core performance.
Install an Aftermarket Exhaust System
The first step to increasing your top speed is adding an aftermarket exhaust system. Adding an aftermarket exhaust will increase the horsepower and torque output.
Performance gains from this upgrade are especially noticeable in the low-end powerband. This can help you accelerate out of corners and off jumps faster, but it will also make your engine lug more at slow speeds.
Tweak the Gearing
The KX250F’s stock gearing is 14/51, which means that the rear sprocket has 51 teeth, and the countershaft sprocket has 14 teeth. Changing the gearing changes the ratio between those two sprockets and, in turn, changes the top speed of your motorcycle.
KX250F’s have enough power to easily change the rear sprocket by a couple of teeth in either direction. You can increase top speed by changing your sprockets to a smaller ratio, say 15/51. But remember, if your bike is geared too high, it will not have enough torque to get out of its own way.
Add a Turbocharger
Consider adding a turbocharger to your KX250F if you seek significant speed increases. You can have this system installed at any authorized Kawasaki dealer or any shop experienced with installing turbocharger systems on motorcycles.
A turbocharger will enable you to significantly increase the amount of oxygen flowing through your engine without adding any additional weight to your bike.
Adjust the Suspension Settings
The suspension of a KX250F is tuned at the factory to provide optimal performance with a standard-sized rider. However, if you are heavier than average, you may want to increase the speed at which the forks and shock compress increase the bike’s top speed.
Your local motorcycle dealer can adjust the suspension settings for your weight, or you can do it yourself using a fork air pump, a shock air pump, and a small wrench. To ensure both shocks are adjusted evenly, use an adjustable wrench to turn the clickers in (hard) before making any adjustments. Make adjustments one at a time to see what effect each adjustment has on handling.
Remove the Rev-Limiter
The rev-limiter on the KX250F is set to prevent the engine from spinning too rapidly and over-revving. The rev-limiter cuts out the spark at the top of each revolution. You can safely remove this rev limiter to maximize the bike’s power and increase top speed.
Kawasaki KX250F – Pros and Cons:
The KX250F is a well-rounded motocross bike with many pro features and few cons. Listed below are some pros and cons of this widely used dirt bike.
- Handling: The KX250F has a reputation for excellent handling, which is not surprising given its position as one of the lightest bikes in the class.
Its narrow and compact frames incorporate Kawasaki’s Ergo-Fit technology, allowing easy weight transfer from front to rear. The suspension and chassis are well balanced, with the ability to quickly absorb bumps and maintain traction on various surfaces.
The stock settings are on the soft side, but dialing them in for your weight and riding style will easily yield a well-balanced bike. It’s easier to handle than some of its faster competitors with decent power.
- Power Delivery: The KX250F is a highly potent power plant, and the 2022 version delivers an even broader spread of power with a wider range of useable energy. It doesn’t have a “hit” like some of the other bikes in this class, but it pulls hard off the bottom and revs cleanly to redline.
Its almost linear, controllable power delivery makes this bike easy to manage in tight or technical areas. It’s also a very smooth motor, with no stutters or hiccups anywhere in the rev range.
- Throttle Response: Since the earlier makes, the instant throttle response has always been a strong point of the KX250F. The power comes on with a smooth but rapid surge, and it feels like the engine has almost no flywheel effect at all. It feels like a two-stroke ride, but it pulls much harder than any 250 two-stroke can.
- Launch Control Mode: KX250F’s KLCM launch control mode can help riders avoid skidding off the road during hard starts. The handlebar switch activates the system by pushing the start button hidden within the bike’s ECU. Upon activation, it promptly restricts engine rpm to approximately 9000 rpm until you shift into the second gear.
- Soft Front Brake: The KX250F’s front brake is a little soft—not spine-wrenching like the old Honda CRF450’s but not much power for such a light bike. The lack of feel doesn’t help either, so you may often have to squeeze hard to get a good bite on the rotor. A Brembo master cylinder could cure this problem.
- Bulky Radiator: The radiator shrouds are a little bulky and could use more trimming, but the bike is still relatively slim. You may not have any problems getting stuck on logs or rocks in the woods, but the radiators do make it a little challenging to pick the bike up off the ground when you stall it since they point out wide.
- Dirt Build-Up on Airbox Side Cover: The airbox side cover is a handy feature, but dirt gets caught between the cover and the frame. This buildup often causes an irritating rattle when you ride over rough terrain until you pop it off and remove the dirt buildup.
Below you will find answers to some commonly asked questions about Kawasaki’s KX250F.
Is a KX250F a good beginner bike?
No. A KX250F is a good motorcycle, but it is not a beginner bike. It’s a race-oriented off-road motorcycle having four-stroke power with a lot of torque, which means relatively quick acceleration on the street. You will need extensive motorcycle experience to control this acceleration on the road.
How much does a Kawasaki KX250F cost?
In the USA, the Kawasaki KX250F has a Manufacturer’s Suggested Retail Price (MSRP) of $7,999. However, you can get it from several dealerships for as low as $7,400.
Is a KX250F a good trail bike?
Ans. The KX250F is a good trail bike. Its 19″ rear wheel is the same size as most street bikes (for comparison, the larger offroad bikes have 21″ front wheels and 19″ rear wheels). It’s not much broader than a street bike, so it’s easy to fit on narrow trails.
Is the KX250F a race bike?
The short answer is yes. The KX250F, like the KX 450F, is a race bike, and, overall, it’s a decent one. That said, if your goal is to ride or race motocross—not just own a motocross bike—the 250F is the best choice.
What are the height and weight of KX250F?
The bike’s height is 49.8 inches from the ground to its handlebars. It weighs 226.4 pounds curb weight and as much as 237 pounds when fueled up.
Overall, it’s undeniable that the KX250F is an excellent option for serious motocross racers and hard-working riders. If you have the budget and can accommodate the bike’s weight and size, then the KX250F should be at the top of your list.
The bike does indeed have all the performance features you need to win races, including its race-bred suspensions, the power to send you to third gear before you know it, and hot styling that will turn heads wherever you are.
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