First Look: 2018 Yamaha YZ450F Dirt Bike

The calendar shows that it's not yet half-past 2017, but Yamaha is already kicking off the 2018 season with a very impressive new YZ450F motocross machine loaded with extensive and impressive changes. There's an all-new engine, new frame, upgraded suspension, slimmer bodywork and electric-start only, plus an industry first: a wireless smartphone-based engine tuning setup with on-board Wi-Fi that allows owners to tune their bike anywhere.

This groundbreaking Yamaha Power Tuner iOS and Android App and communication control unit can make EFI and ignition mapping changes wirelessly via an onboard Wi-Fi system for the ultimate in track-side tuning. Also, a "log" function allows riders to make notes about the day's riding location, conditions, bike settings and more to provide a baseline for future dirt bike rides. This app can also monitor a range of information such as RPM, throttle position, engine coolant temperature and more, plus a maintenance function with customizable trip meters to monitor run times.

Convenient tunability is a big plus, given that the basic engine package is a good one—and the new 449cc powerplant for 2018 looks to be very good indeed. The distinctive Yamaha single with its rearward-slanted cylinder design features an all-new, lighter cylinder head with improved air flow, and the cylinder slant is more upright to work with the bike’s updated frame for optimized weight distribution. More aggressive camshaft profiles, a new crankshaft, a stronger, high-compression “box bridge” piston design with a DLC-coated (Diamond-Like Carbon) piston pin, and new 44mm Mikuni throttle body are some of the major highlights. Upgrades were also made to the gearbox and clutch and now there’s also a compact starter motor located right behind the cylinder for convenient push-button starting—no kickstarter assembly! The starter’s powered by a high-capacity ultra-lightweight lithium-ion battery for minimal weight.

The engine mounts in an all-new aluminum bilateral beam frame with redesigned upper frame bracing, rear frame spars, steering head and all-new engine mounts to provide optimal bump absorption and effortless cornering. The next-gen suspension components include a fully adjustable KYB coil spring-type fork with speed sensitive damping, and the single KYB shock boasts new damping characteristics and a reservoir that’s up 30cc in capacity to increase damping control during long motos.

There’s also new, lighter, compact bodywork from tip to tail, and 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 8mm up front and almost 20mm at the tail end, giving the rider better maneuverability on the bike.

For 2018, the YZ450F will be available in either Team Yamaha Blue or White color schemes, and they will arrive at Yamaha dealers starting in August 2017 with a MSRP of $9,199.