250CC Liquid-Cooled DOHC 4-Valve Engine
A new engine offers YZ250F riders the best balance of high-rpm power with a broad, useable powerband. The new, higher-compression piston and new intake and exhaust valving delivers outstanding engine character with a focus on top-end power delivery. The cylinder is also lighter and angled more upright to improve mass-centralisation.
Aluminium Bilateral Beam Frame
The new compact bilateral beam frame is completely new to further refine the instinctive handling the YZ250F is known for. Larger upper frame bracing improves rigidity and durability, while wider rear frame spars and all-new engine mounts centralise mass for the best possible balance of bump absorption, stiffness and feeling of grip.
Smart Phone Tuning
Yamaha broke new ground with the YZ450F Power Tuner app by allowing convenience, flexibility and tunability via your iPhone or similar. Now the 250F can accept fuel and ignition timing changes instantly – you can upload them to the bike via the onboard WiFi system for the ultimate in track-side tuning and engine diagnostics.
Adjustable Engine Maps
Two-mode adjustable engine mapping allows the rider to adjust engine character with the push of a handlebar mounted button, making it easy to tune the YZ250F for changing track or weather conditions between motos.
Electric Starter System
Utilising a compact starter motor and ultra-lightweight lithium battery, the YZ250F brings the convenience of push-button starting to the racetrack, for effortless restarts under pressure, and relaxed riding when the clock isn’t ticking. Powered by a high-capacity and ultra-lightweight, four-cell lithium-ion battery, the system adds minimal weight.
Yamaha continues to use spring-type forks with refined, speed-sensitive damping to give industry-leading suspension performance straight out of the box. 2019 brings updated settings to match the updated frame and engine layout.
The transmission gears, dogs and shift mechanisms are designed to smooth gear changes and improve durability under the heavy demands of motocross racing, even with lighter gears and selector drum for 2019. The updated YZ250F also features a larger-diameter clutch to boost reliability even further under high-heat conditions.