2022 Yamaha Two-Stroke Motocross Range

Yamaha effectively invented the modern era of four-stroke motocross machines at the beginning of this century with the YZ400F, YZ426F then YZ450F and YZ250F that heralded a quantum shift in the development direction of the motocross scene. All the other Japanese brands followed suit and all but Yamaha eventually gave up making full-size two-stroke motorcycles of any description, some still make a couple of two-stroke powered junior machines but for the big boys the cupboard is largely bare unless you want to go European.

While Yamaha have continued to produce and sell their legendary YZ125 and YZ250 two-strokes, it is fair to say that they have not put much R&D resources behind the two-bangers and over the last decade. The YZ machines have largely rolled on from year to year virtually untouched, save for a minor tweak here and there. Conversely the Europeans have continually developed their two-strokes but much of that development has been focussed on enduro racing rather than motocross, with major investments in the switch to fuel-injection for Enduro, but their motocross machines all remain carburettor fed.

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2022 Yamaha YZ125

For model year 2022 though Yamaha have come through for the big boys with an essentially all-new YZ125, the first full change in more than 15 years for the ring-dinger that got so many people first started on dirt-bikes.

The liquid-cooled 125cc two-stroke engine has been thoroughly reworked to produce more power. Every functional part of the 2022 YZ125 engine is new, including the cylinder body, cylinder head, piston, piston pin, connecting rod, crankcase and expansion chamber.

It all adds up to increased power across the mid- to high-rpm range. Enhancing fuelling and power delivery, a new high-precision Hitachi Astemo Keihin PWK38S carburettor with throttle position sensor and 3D-map-controlled CDI unit provide clean, crisp throttle response and superior rideability. A new intake design with VForce4 carbon reed valve leads to a more efficient draw of air into the engine for an improved feeling of power in the low rpm range.

To match increased engine performance, an updated lightweight braking system features larger front pistons, a more rigid caliper, a redesigned 270mm front rotor with a 30% increase in pad contact area and higher friction pad material, all combining to provide exceptional braking power and feel.

A redesigned rear rotor maintains the same braking power while dropping outer diameter from 245mm to 240mm, reducing unsprung weight without compromising performance.

Taking the YZ125’s category-defining suspension and handling characteristics to a new level, front and rear suspension damping has been revised to further improve bump absorption and cornering performance. KYB suspension includes an inverted front fork, now with new fork internals for more precise damping.

A new flatter seat and more narrow fuel tank design, along with smoothly integrated body panels and slimmer radiator shroud width all combine to enable greater freedom of movement forward and back, allowing the rider to easily shift body weight for increased control and confidence.

YZ125 will be available in Team Yamaha Blue or Monster Energy Yamaha Racing Edition with premium embedded graphics to ensure outstanding durability and scratch resistance. Availability for both models are due in Q4 2021 with Ride Away Pricing – $10,799 for Team Yamaha Blue and $10,899 for Monster Energy Yamaha Racing Edition.

2022 Yamaha YZ125 at a glance

• Redesigned liquid-cooled Yamaha Power Valve System (YPVS) 125cc two-stroke engine boasts more power in the mid- to high-range for increased usability over the previous model
• New high-precision Hitachi Astemo Keihin PWK38S carburettor features throttle position sensor and 3D-map-controlled CDI unit resulting in crisp throttle response and superior rideability
• New straight intake design improves feeling of power in the low rpm range
• New shorter, lighter muffler
• High performance brake setup features more rigid front caliper, larger front pistons and redesigned rotors with increased pad contact area for exceptional stopping power and feel, along with less unsprung weight
• Improved rider ergonomics with a narrower tank, flatter seat and slimmer radiator shrouds offering greater freedom of movement
• Fully adjustable KYB inverted front fork now includes a leaf spring in the mid-speed valve for increased performance and comfort
• Revised fully adjustable KYB rear shock features reduced-friction Kashima Coat internals
• Race-proven, highly developed forged aluminium semi-double cradle frame
• Removable aluminium rear subframe constructed of square-section tubing for reduced weight
• Lightweight finely tuned chassis for nimble handling, more control and less rider fatigue
• Revised six-speed, close-ratio transmission has wider transmission gear tooth width and new, optimised gear ratios for maximum performance
• New lightweight rear sprocket design
• New lightweight chain
• High-capacity radiator features a 10-row core with blacked-out louvres to deliver maximum cooling and aggressive looks
• Lightweight aluminium handlebar with two-position adjustable handlebar clamp
• Adjustable clutch lever with cable adjuster
• New premium graphics are now embedded for improved durability and scratch resistance
• Race-developed Bridgestone Battlecross X20 tyres

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2022 Yamaha YZ250

While the 125 scores an all-new engine the YZ250 continues with its high-revving but reliable powerplant but that is now fed via straighter intake design, allowing a more efficient intake path to the engine for a better feeling of power in the low rpm range.

Rider ergonomics have come in for attention, a more narrow fuel tank, flatter seat, slimmer radiator shrouds and new side covers all contribute to greater freedom of movement front to back and easier weight transfer.

The YZ250’s already renowned suspension and handling performance takes another step forward with revised front and rear suspension damping to enhance bump absorption and cornering agility.

An updated brake setup includes a more rigid front caliper, larger front pistons, a redesigned 270 mm front rotor with a 30% increase in pad contact area and higher friction pad material, all combining to provide exceptional braking power and feel.

A redesigned rear rotor maintains the same braking power while dropping outer diameter from 245mm to 240mm, further reducing unsprung weight.

Wrapping up the package, a premium new Yamaha Blue and dark blue embedded graphics scheme provides outstanding durability and scratch resistance while accentuating the YZ’s racing pedigree. The 2022 YZ250 will also be available in Monster Energy Yamaha Racing Edition colour scheme.

The 2022 YZ250 retains the fast and fun liquid-cooled YPVS-equipped 249cc two-stroke powerplant, the compact chassis, highly developed lightweight aluminium frame, and the intuitive handling character and usability that’s made it a favourite among competitive motocross racers and recreational riders alike.

Availability is August 2021 with Ride Away Pricing – $12,099 for Team Yamaha Blue and $12,199 for Monster Energy Yamaha Racing Edition.

2022 Yamaha YZ250 at a glance

• Improved rider ergonomics with a narrow tank, flatter seat and slimmer radiator shrouds offering greater freedom of movement
• Advanced liquid-cooled YPVS-equipped 249cc two-stroke engine is lightweight, compact and fun, with a wide, hard-hitting powerband
• New straight intake design improves feeling of power in the low rpm range
• Advanced Hitachi Astemo Keihin PWK38S carburettor with power jet and throttle position sensor provides extra-crisp throttle response
• High performance brake setup features larger front pistons, more rigid caliper and redesigned rotors with increased pad contact area for exceptional stopping power and feel, along with less unsprung weight
• Fully adjustable KYB fork features the Speed-Sensitive System for precise handling and superb shock absorption
• Revised fully adjustable KYB rear shock features reduced-friction Kashima Coat internals
• Race-proven, highly developed forged aluminium semi-double cradle frame
• Removable aluminium rear subframe constructed of square-section tubing for reduced weight
• Finely tuned lightweight chassis and advanced suspension endow the YZ250 with class-leading handling
• Smooth-shifting, five-speed, close-ratio transmission ensures confident gear changes in all conditions
• New lightweight rear sprocket design
• New lightweight chain
• High-capacity radiator features a 10-row core with blacked-out louvres to deliver maximum cooling and aggressive looks
• Lightweight aluminium handlebar with two-position adjustable handlebar clamp
• Adjustable clutch lever with works-style cable adjuster
• Premium new graphics are now embedded for improved durability and scratch resistance
• Race-developed Dunlop Geomax MX33 tyres

Source: MCNews.com.au