We have already revealed the trick new YZ65 that made us yearn to be kids again, and now Yamaha unveil the next step on the MX ladder with the all-new YZ85 LW in both big and small wheel versions.
Like the new 2019 YZ250F which we also showcased today, the 2019 junior MX ace model is also new from the ground up – and the winning two-stroke is now fitted with Yamaha’s YPVS power valve system to improve performance.
Plus many of the new YZ85 parts are interchangeable with the smaller YZ65, making the step up even less hassle for your young gun’s mechanic and sponsor – also known as dad.
The outgoing model won the 2018 Australian Junior National title so it was alreayd on the pace but the new 2019 YZ85 is now fitted with a new engine complete with revised intake, exhaust and transmission. Add to that new front forks, anew swingarm, new wave-style brake rotors, adjustable ergonomics and more.
The 85cc liquid-cooled, two-stroke engine now features the Yamaha Power Valve System for broad, tractable power across the rev range without losing peak power at high rpm — improving driveability and reducing the need for frequent shifting.
A new cylinder head and longer connecting rod design work together to boost compression ratio for enhanced power
output.
A new crankcase design features a spacer-style reed valve intake for improved gas flow, which inhales through a 28mm Keihin flat-slide carburettor for seamless throttle response.
Matched to the improved output of the YPVS engine, the new expansion chamber optimises exhaust gas flow for enhanced power delivery, especially in the low- and mid-range.
Revised for 2019, the transmission increases the width of selected gears to provide enhanced gear engagement and smoother shifts.
Lightweight radiator has large cores and louvers, and the water pump features a cast aluminum (vs. resin) impeller for maximum cooling efficiency.
Airbox design ensures excellent air cleaning performance and easy maintenance.
Lightweight 36mm KYB inverted cartridge fork features 274mm of travel with compression and rebound damping adjustability with low-friction outer tubes and internals. For 2019, one-piece outer tubes and new settings offer enhanced performance across a range of conditions and rider abilities.
The rear suspension features fully adjustable Kayaba link-type shock with 282mm of travel and race tested compression valving. The progressive linkage-type design improves bottoming resistance, while updated settings improved bump absorption and bottoming resistance allowing racers to charge harder and improve lap times.
Redesigned swingarm features a new composite chain guide as well as updated chain adjusters for easier maintenance. The compact rear subframe is removable to allow easy maintenance.
For 2019, a new front brake line improves braking feel, while wave-style brake discs offer improved self-cleaning and cooler-running performance. The 220mm front disc and 190mm rear disc deliver strong, precise stopping power.
Lightweight 17-inch front and 14-inch rear rims are durable and reduce unsprung weight for optimal suspension performance.
New four-position adjustable handlebar mounts and taper-style handlebars allow the rider to tune the handlebar position to suit their size and preferences. The flat fuel tank, radiator shrouds, side panels and rear fender provide generous freedom of movement.
The new YZ85 comes in two variants with different sized wheels. The standard model with 17in front and 14in rear wheels is priced at $6799 and the LW model with 19in front and 16in rear wheels is priced at $7399 RRP inc GST.
Note that the changes made to this model mean that the race kit that was previously supplied to make the YZ85 competitive is no longer required. Race it straight from the crate from early August!
