Yamaha 2017: Off-Road Models are Back, Big and bLU

Like ite motocross sister, the 2017 Yamaha YZ250FX gets the most primping in Yamaha’s 2017 off-road lineup.

Who would’ve ever thought there would come a day when Yamaha would have more off-road specific competition models on offer than all three of their Japanese rivals combined?

That’s a testament to just how busy Yamaha has been in revamping its entire dirtbike range over the past three years, most recently with the introduction of its WR450F, YZ450FX and YZ250X two-stroke, all three hot on the heels of all-new WR250F and YZ250FX models. The YZ250FX is so popular that it is the number-one selling closed-course country off-road model regardless of displacement category, according to Yamaha.

But Yamaha wasn’t about to rest on that laurel, and since it was combing through the 2017 Yamaha YZ250F anyway, why not take advantage of those updates for the YZ250FX as well?

Sounds like a good idea to us. After all, the motocrosser begat the off-roader, although there are numerous features that differentiate the FX, such as electric starting, different transmission ratios, a different ECU and suspension tuning, and 18-inch rear wheel. For 2017, the YZ250FX receives more changes than the YZ250F, but those changes actually pull the two machines a little closer together in terms of their overall specifications.

Mechanically speaking, the YZ250FX is now closer to the YZ250F than before. Its liquid-cooled, fuel-injected, DOHC, 249cc Single already shared the same 77.0 x 53.6mm bore and stroke, and the same 13.5:1 compression ratio, but for 2017 Yamaha updated the FX engine to more closely mirror the YZ250F, starting with the swap to the same Bridge-box design piston, which shaves weight by 10%. The piston pin also receives Diamond-like Coating (DLC), and its underside is now cooled by an oil jet. Down below, the crankshaft now receives thrust washers to help reduce lateral crankshaft movement at high rpm. The crankshaft and counterbalancer have also been rebalanced to help give the engine a smoother, more predictable power delivery. Like the 250F, the FX also gets a new steel connecting rod with more nickel in the mix for better high-rpm reliability.

One FX specific change to the engine involves taking something away rather than adding it: For 2017 the YZ250FX (and YZ450FX) will be delivered from the factory sans kickstarter and kickstart mechanism. That means no backup is in place should your FX’s battery fail, but Yamaha is confident that its battery and starter system are up to the task of lighting off the bike as needed, and ditching the kick starter and required gears shaves a none-too-insignificant 1.74 lbs. off each machine. That’s a big difference, considering that the electric starter and larger generator added 18 lbs. of weight to the original FX when compared to the motocrosser.

Beyond that, the 2017 250FX gets the same engine changes as the 2017 YZ250F, and for the same reasons. To boost top-end power, the FX gets the new reversed cylinder head with revised intake and exhaust port shapes, and the intake side now boasts an even straighter angle to give the incoming fuel charge a straighter shot into the combustion chamber. The effective length of the intake tract has also been reduced via a 15mm shorter air funnel above the F’s 44mm Keihin throttle body. The intake side of the throttle body has also been altered to match the shape of the intake port for improved air flow.

To help fill the new cylinder head more efficiently, the FX features more aggressive intake and exhaust camshafts. Yamaha has also increased the diameter and changed the shape of the 250F’s wraparound mid pipe in an attempt to boost top-end performance even more. The FX’s ECU has also been retuned, and it now features a more progressive rev limiter to give the engine a better overrev feeling and a less abrupt cutoff at its 14,000 rpm redline.

The YZ250FX’s clutch and five-speed transmission have also been refined. The cable-operated clutch receives a new bushing to give a lighter and smoother feel, and the second-, third- and fourth gears have been beefed up for increased strength. Yamaha engineers also opted for a different shift lever shape and material to give the transmission a smoother shift feel.

The YZ250FX’s bilateral beam chassis is also changed to give it a better flex character in the off-road environment. The forged swingarm pivot sections are now wider, increasing the total width of the frame by 12mm, and the engine mounts feature different shapes and material than the 2016. The upper mounts are still aluminum, but the lower mounts are now made of steel.

The YZ250FX’s fully adjustable 48mm KYB coil spring fork with Speed Sensitive damping has also been revised for 2016, including new fork tubes that are thicker in some spots along with new fork seals and a new fork scraper to protect against fouling by foreign materials. Front suspension travel is 12.2 inches. Out back, a fully adjustable KYB monoshock with a massive 50mm piston inside its piggyback reservoir delivers 12.4 inches of travel through a rising-rate linkage system. The suspension settings at both ends has been revised to balance the suspension performance with the upgraded chassis.

Also like the YZ250F, the YZ250FX gets a new air filter cover that better guards its quarter-turn Dsuz fasteners from being snagged by boots and knee guards and falling off the machine.

The 2017 YZ250FX also gets a new 270mm front brake (up from 250mm last year), and there has been a change to the 245mm rotor out back. The rear rotor is made of a new material that provides better heat resistance than the previous rotor. Other new features include a heavy-duty plastic skid place to protect the lower frame from rocks, roots and other objects, and a new fuel level sensor and warning light to indicate when the fuel level is getting low; these features were pirated from the WR250F.

The 2017 YZ250FX’s suggested retail price is $7999, and it will hit dealer showroom floors in August.

The rest of the 2017 Yamaha off-road lineup returns with minimal changes. The YZ450FX is back with new graphics and revised suspension settings. The 450FX’s 48mm KYB Speed Sensitive fork also receives the new oil seals for enhanced durability as well as the redesigned air filter cover and the WR-style fuel-level sensor and warning indicator. The 450FX will retail for $8999 and hit dealerships nationwide in August.

The 2017 Yamaha WR450F returns with new graphics and will retail for $9099. Ditto for the 2017 WR250F, which will retail for $8099. Both machines will be available in July. The 2017 YZ250X two-stroke will receive new graphics and will retail for $7499. It will be available in August. All of Yamaha’s off-road models will be available in blue/white. No optional color scheme will be offered as it is on the motocrossers.