SPY PHOTOS: 2018 YAMAHA YZ250F & YZ450F

On May 10, 2017 Last updated Jun 12, 2017

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This is the bike that started the four-stroke revolution for Yamaha. Doug Henry’s 1997 prototype YZ400F which lead to its production in 1998.

Yamaha Motor Corporation has unveiled their 2018 YZ450F with electric start—featuring the world’s first smartphone engine tuning app for a production motocross bike. An all-new engine, new frame, new bodywork and more changes are also major focal points of the extensive model redesign.

“The 2018 YZ450F with all-new technology, power and performance connects YZ riders to their bikes like never before and will launch Yamaha riders into the victory zone when bikes hit dealers in July,” said Mike Doughty, Yamaha’s General Manager of Motorcycle Operations. “With the all-new design and performance features of the 2018 model, the YZ450F enters a new era of advanced racing technology that brings the ultimate balance of power, confidence and customization to Yamaha riders.”

For 2018, the YZ450F now joins KTM, Husky and Honda in the push button electric start club.

The 2018 YZ450F utilizes an all-new engine design that features a new cylinder head, piston, camshaft profiles, cylinder geometry and more. The bilateral-beam aluminum frame is all-new with an optimized engine mounting position in hopes to improve the machine’s rigidity balance, improving cornering ability and traction.

WORLD’S FIRST PRODUCTION POWER TUNER APP

Smart phones are sure living up to their name. The YZ450F hass a Wi-Fi feature onboard that can connect to your Android or iPhone smartphone (after you have downloaded the app—which is free with purchase of bike). It allows you to adjust the ignition and fuel the mapping as well as many other features.

The 2018 YZ450F is the world’s first production motocross bike with a wireless smartphone based engine tuner. The all-new Yamaha Power Tuner iOS and Android App and communication control unit connects the rider with the bike like never before. The new Yamaha Power Tuner app can make fuel and ignition mapping changes – uploaded wirelessly to the bike via the onboard Wi-Fi system – for the ultimate in track-side tuning. A “Log” function allows you to make notes about your riding location, conditions, bike settings and more, giving you a baseline for future rides. The app can also monitor a range of information such as RPM, throttle position, engine coolant temperature and more. There is also a maintenance function with customizable trip meters to monitor run times for items you decide.

The new Yamaha Power Tuner app released with the 2018 YZ450F makes it possible to modify engine mapping in even greater detail than before. It also allows users to share settings among their team or with friends (along with other information) thus evolving the system into a tool that helps facilitate communication.

ALL-NEW ELECTRIC START

The 1.5 pound Lithium-Ion battery that powers the starter has a battery capacity of 13.2 volts.

Utilizing a compact starter motor and 1.5 pound lithium-ion battery, the 2018 YZ450F brings the convenience of push-button starting to the racetrack for effortless restarts under pressure and relaxed riding when the clock isn’t ticking.

NEW ENGINE

Yamaha’s rearward-slanted engine design has been updated with an all-new cylinder head, new cam profiles, new crankshaft, high-compression bridge-box piston design and much more.

For 2018, Yamaha has refined its distinct rearward-slanted cylinder design for the YZ450F engine – complete with a rear exhaust and forward-mounted downdraft intake system. The all-new cylinder head is lighter and the cylinder slant is more upright to work with the bike’s updated frame for optimized front weight distribution. Inside, the engine features new camshaft profiles, a new crankshaft, a stronger high-compression “bridge-box” piston design with a DLC-coated (Diamond-like Carbon) piston pin, and now breathes through a new 44mm Mikuni EFI throttle body.

The transmission and clutch have been overhauled for a more direct connection as well as enhanced durability. Revised gears with a wider surface area, updated clutch plates and a stiffer outer pressure plate all combine in hopes to boost controllability and durability.

The YZ450F radiators and exhaust have also been modified. The updated radiators are larger and angled more directly towards the incoming air stream for improved cooling under the most demanding race conditions. The wraparound exhaust pipe has a revised geometry for 2018. This layout moves the rear end of the exhaust pipe farther forward and enables a muffler position closer to the center of the mass.

Returning for the 2018 model, Yamaha’s Launch Control System (LCS) is integrated into the YZ450F.

NEW FRAME AND OPTIMIZED ERGONOMICS

The YZ450F frame has been completely redesigned for 2018.

The all-new compact bilateral beam frame has redesigned upper frame bracing and rear frame spars. The all-new engine mounts centralize mass and increase rigidity on lateral, horizontal and vertical axis.

Surrounding this fully redesigned chassis, the 2018 YZ450F feature new, lighter, compact, plastic bodywork from tip to tail. The radiator shrouds incorporate a new air duct with a concave shape that is narrower. The seat height has been reduced by 8mm towards the front and almost 20mm lower at the tail end.

EASILY TUNED KYB COIL SPRING SUSPENSION

The class leading KYB SSS forks have updated settings due to the new chassis.

The industry-leading, fully adjustable KYB coil spring-type fork with speed sensitive damping provides exceptional balance between handling and bump absorption for race-winning performance. The KYB shock boasts new damping characteristics to match the new chassis. The reservoir has been increased 30cc to increase damping control during long motos.

Available in either Team Yamaha Blue or White color schemes, complete with the onboard Communication Control Unit (CCU) and the Yamaha Smartphone Power Tuner app, the all-new 2018 YZ450F will arrive at Yamaha dealers starting in August 2017 with a MSRP of $9199.

BLUE RIMS FOR THE 2018 YZ250F

The conly visible changes to the 2018 Yamaha YZ250F are the graphics and the blue rims. Yamaha’s 2016 AMA West Coast Supercross and AMA Motocross Championship-winning YZ250F returns powered by its high-performance 250cc four-stroke, fuel injected engine with a forward position downdraft intake to deliver optimum engine power. The proven bilateral beam aluminum frame concentrates mass by moving key components like the fuel tank and exhaust muffler towards the center of the bike. An industry-leading, fully adjustable KYB spring-type front fork and a KYB rear shock combine to provide excellent handling characteristics. The 2018 YZ250F will begin arriving at Yamaha dealerships in July in both Team Yamaha Blue and White color schemes with a $7699 MSRP.