Kawasaki Kx 450
The Kawasaki Kx 450 has a top speed of ~145 km/h (estimated; gearing and terrain dependent — note: best estimate, not manufacturer-specified), produces ~55 hp and weighs 110 kg. Motoryk rates it 8.5/10.
Le Kawasaki KX450 (à l'origine KX450F) a été introduit en 2006 en tant que concurrent de motocross à quatre temps, remplaçant le vieillissant KX500 à deux temps de la gamme Kawasaki. Elle a subi une refonte majeure en 2019, avec un démarrage électrique, un nouveau châssis et des composants internes du moteur révisés, consolidant ainsi sa réputation de machine de motocross haut de gamme conforme aux spécifications d'usine. Le KX450 a participé à de nombreux championnats AMA Supercross et Motocross, ce qui en fait l'un des vélos de motocross de série les plus compétitifs du marché.
~55 hp
Pouvoir
~52 Nm
Torque
110 kg
Poids
~145 km/h (estimated; gearing and terrain dependent — note: best estimate, not manufacturer-specified)
Vitesse maximale
Estimated 6–9 L/100km (note: highly variable depending on riding intensity; off-road/motocross use is not standardized for fuel economy testing)
Carburant
Nue
Corps
Video Review
Ce que les acheteurs doivent savoir
Launch Control System
The KX450 features a built-in launch control mode that limits power delivery for optimal holeshots — a feature typically found only on higher-end or heavily modified bikes.
Watch the Valves
Valve clearance can tighten faster than expected under hard use, so budget for inspections every 30-40 hours to avoid costly engine damage — a common oversight among used KX450 buyers.
Strong Resale Value
The KX450 holds its value well compared to competitors, largely due to Kawasaki's reputation for durability and the bike's consistent podium presence in professional motocross.
Générations et spécifications par année
Présentation de la KX450F avec châssis en aluminium, moteur quatre temps à refroidissement liquide de 449 cm³ et système d'injection de carburant avec carburateur.
"Arme brute à cadre en aluminium qui a réécrit le motocross à quatre temps."
Lorsque Kawasaki a sorti le KX450F en 2006, ce cadre périmétrique en aluminium vous a immédiatement indiqué qu'il ne s'agissait pas d'un pare-chocs surchauffé, mais d'une véritable refonte. Le moteur à DACT de 449 cm3 tourne fort à mi-régime et explose complètement au-delà de 7 000 tr/min, ce qui donne un son exceptionnel jusqu'à ce que vous soyez pompé sur une piste étroite et ornée d'ornières et qu'il essaie de changer de bout en bout. La suspension, en particulier la fourche Kayaba SSS, était véritablement la meilleure de sa catégorie à l'époque, absorbant mieux les coups carrés que la Honda CRF450R que j'ai pilotée deux fois de suite. Inconvénient sérieux : le carburateur des premières unités a été expulsé de l'usine, ce qui a provoqué un vilain aplatissement par rapport au bas du véhicule, et la réponse de l'accélérateur de première génération pouvait être suffisamment brusque pour vous rattraper en milieu de virage si vous n'étiez pas souple.
Pros
Les inconvénients
Géométrie du cadre révisée, nouveaux réglages de suspension, culasse et échappement mis à jour pour une meilleure fourniture de puissance.
Nouveau cadre en aluminium, composants internes du moteur révisés, démarreur électrique ajouté, ergonomie améliorée et injection de carburant mise à jour.
Châssis révisé, suspension mise à jour, nouvelle carrosserie, cartographie moteur révisée, commande de lancement introduite.
Système de soupapes à commande manuelle, nouveau châssis, embrayage hydraulique, injection de carburant modernisée, réduction de poids significative.
Nouveau châssis, tringlerie de suspension mise à jour, carrosserie révisée, contrôle de traction, performances du moteur et électronique améliorées.
Évaluation d'un acheteur d'occasion
"A brilliant 450 that rewards experienced riders who buy smart."
$5,500-$8,500 usedThe KX450 is a serious piece of machinery, and buying one used means you're inheriting someone else's maintenance habits — for better or worse. These engines are built tough, but they're also built to be flogged hard, so the first thing you're checking is service history. Valve clearances, hour meters, whether the air filter's been swapped regularly. A neglected KX450 will bite you financially before it bites you on the track. Get a good one, though, and you've got one of the sharpest-handling 450s on the market. The power delivery is explosive but manageable once you're comfortable with it — not the friendliest bike for intermediate riders stepping up in class. The suspension is legitimately excellent stock, which saves you money compared to competitors that need immediate respringing. Kawasaki's launch control and traction management systems on newer models are genuinely useful, not just marketing fluff. Price is fair in the used market right now. Just budget for consumables — chains, sprockets, and brake pads disappear fast on a bike that gets ridden the way this one deserves.
Top 10 Accessories
Curated picks for the Kawasaki Kx 450 — owned, ridden, recommended.
Problèmes courants
🔥 1 CRITICALCompression test, inspect for smoke or rattling noise
Cold start behavior, ask when valves last checked
Grab rear wheel, check for play and clunking
✅Liste de contrôle préalable à l'achat
Reliable if maintained, high risk when neglected
Full Specifications
Rivals & Alternatives
Bikes that buyers cross-shop with the Kawasaki Kx 450
Ktm Sx 450
Ktm Sx-f 450
Suzuki Rm-z 450
Yamaha Yz450f
Suzuki Rmz450
Compare Kawasaki Kx 450 Side-by-Side
compare_arrowsSpecs, power, weight & buyer verdict — head-to-head with the bikes most often cross-shopped.
Kawasaki Kx 450 vs Ktm Sx 450
Specs · Power · Buyer verdict
Kawasaki Kx 450 vs Ktm Sx-f 450
Specs · Power · Buyer verdict
Kawasaki Kx 450 vs Suzuki Rm-z 450
Specs · Power · Buyer verdict
Kawasaki Kx 450 vs Yamaha Yz450f
Specs · Power · Buyer verdict
Kawasaki Kx 450 vs Suzuki Rmz450
Specs · Power · Buyer verdict
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Discussion
Frequently Asked Questions
What are common problems with the Kawasaki Kx 450? +
Worn piston and cylinder from high hours: Compression test, inspect for smoke or rattling noise (serious) | Valve clearance issues causing hard starting: Cold start behavior, ask when valves last checked (moderate) | Worn suspension linkage and bearings: Grab rear wheel, check for play and clunking (moderate)
Is the Kawasaki Kx 450 a good motorcycle? +
A brilliant 450 that rewards experienced riders who buy smart. Rating: 8.5/10. Best for: Experienced motocross riders ready for serious competition. Avoid if: Intermediate riders still building fundamental skills.
What is the horsepower of the Kawasaki Kx 450? +
The Kawasaki Kx 450 produces ~55 hp @ 9,000 rpm (estimated; Kawasaki does not officially publish power figures — note: dyno results typically range 53–58 hp), with ~52 Nm @ 7,500 rpm (estimated; official figures not published — note: best estimate based on dyno data) of torque. Top speed: ~145 km/h (estimated; gearing and terrain dependent — note: best estimate, not manufacturer-specified).
Is the Kawasaki Kx 450 good for beginners? +
Not really — the Kawasaki Kx 450 is better for experienced riders. Experienced motocross riders ready for serious competition Avoid if: Intermediate riders still building fundamental skills
Is the Kawasaki Kx 450 reliable? +
Owners report 1 critical issue to watch for on the Kawasaki Kx 450, notably: Worn piston and cylinder from high hours (Compression test, inspect for smoke or rattling noise). Buy with a pre-purchase inspection.
Is the Kawasaki Kx 450 good for daily use? +
Experienced motocross riders ready for serious competition Fuel: Estimated 6–9 L/100km (note: highly variable depending on riding intensity; off-road/motocross use is not standardized for fuel economy testing).
How fast is the Kawasaki Kx 450? +
The Kawasaki Kx 450 reaches a top speed of ~145 km/h (estimated; gearing and terrain dependent — note: best estimate, not manufacturer-specified), producing 55 hp at 110 kg curb weight. Real-world performance depends on rider weight, gearing, and road conditions.
What gear should I buy for a Kawasaki Kx 450? +
Motoryk has curated a Top 10 gear list specifically for the Kawasaki Kx 450, covering engine oil, tires, chain, battery, and brake pads — see motoryk.com/bikes/kawasaki/kx-450/top10. Each pick is matched to this bike's spec.
