The 2019 YZ85 gets a massive update, and utilises a newly designed 85cc liquid-cooled, 2-stroke heart featuring a case reed-valve intake and a mechanical Yamaha Power Valve System (YPVS). Combined with redesigned cylinder and head, crankcase, crankshaft, connecting rod, transmission, exhaust and CDI unit, the new YZ engine is said to provide broad tractable power across the rev range without losing peak power at high RPM.
In the frame department, the 2019 YZ85 scores a semi-double-cradle steel frame, removable subframe and redesigned aluminium swing-arm provide a nimble feel, confident handling and ease of maintenance. The ergonomics feature a flat, comfortable seat, four-position adjustable aluminium tapered handlebars and adjustable reach levers to provide comfort and ease of movement for a wide range of young rider sizes.
Braking has also been updated, with a new, stiffer front brake line with new routing improves braking feel, while wave-style brake discs offer improved self-cleaning and cooler-running performance. The 220mm front disc and 190mm rear disc are designed to deliver strong, precise stopping power Yamaha says.
The new YZ85 also features KYB®’s race-proven, fully adjustable 36mm coil spring fork with one-piece outer tubes and tapered shape to provide optimal rigidity balance. This provides exceptional handling, bump absorption and ease of set-up for race-winning performance. The KYB® fully adjustable link-type shock utilises specially designed damping characteristics to match the new chassis.
For 2019, the YZ250F boasts an all-new engine design that features an electric starter, a new cylinder head, piston, cam shaft profile, cylinder geometry, larger diameter clutch and more – all working together to deliver top notch power, with even more mid-top power.
Its bilateral beam frame is completely revamped with an optimized engine mounting position to improve the machine’s rigidity balance, which benefits cornering ability, and traction. Redesigned bodywork and ergonomics provide a lighter and more compact feel that bind rider and machine as one. The class leading KYB® suspension with updated internals provides the optimal balance between comfort and race-winning performance.
Along with all the above, and an addition we’ve suspected would filter down since last year’s YZ450F launch, is that the all-new 2019 YZ250F also comes standard with a Communication Control Unit (CCU) which allows riders to connect wirelessly to their bike, and tune it according to their preferences – all they need is a phone and the Yamaha Power Tuner app.
This works nicely with the two-mode adjustable engine mapping on the YZ250F, which allows the rider to adjust engine character with the push of a button, making it easy to tune the YZ250F for changing track or weather conditions.
As is the the way it seems the moto world is heading, Yamaha have included a compact starter motor and ultra-lightweight lithium-ion battery into the 2019 YZ250F. While it definitely brings the convenience of push-button starting for quick and effortless restarts under pressure and relaxed riding when the clock isn’t ticking, it seems the days are drawing closer when a kick starter won’t be needed anymore, and that’ll be a bit sad for those of us who enjoy kicking their bike into life.
Visually, surrounding the fully redesigned chassis of the the 2019 YZ250F is a new lighter, compact body from tip to tail. The radiator shrouds incorporate a new air duct with a concave shape that not only improves styling, but is also narrower for better knee grip and overall rider movement. The seat height has been reduced by 8mm towards the front and almost 20mm lower at the tail end, giving the rider better manoeuvrability on the bike.