The 2015 Yamaha YZ250F is a slightly refined version of the 2014 model. Photography by Kit Palmer

Yamaha, not a company known to rest on its laurels, didn’t completely ignore its 2015 Yamaha YZ250F after giving it a major rebuild for the 2014 model year, the year it finally received fuel-injection and, like the YZ450F, Yamaha’s unique reversed cylinder configuration. And Yamaha hit the bull’s-eye with the all-new machine. It was a big hit for those lucky enough to ride one, and it was even the big winner in our 2014 250F motocross shootout. And an easy winner we might add, a lot of which had to do with its outstanding motor, solid chassis and suspension, and excellent ergonomics. It was an outstanding all-around package and one that is doing quite well on the outdoor National circuit right now in the hands of Jeremy Martin and Cooper Webb, as well as Christophe Pourcel.

Like last year (2014), the 2015 YZ250F inspires confidence with its stable chassis and nimble handling.

So it comes as no surprise that Yamaha made only minor refinements to the 2015 version, most of them to make the bike more durable.

In the all-important motor department, Yamaha pretty much left well enough alone. The only real performance-minded change it made was to the YZ’s ECU, recalibrating it a bit to readjust and improve power delivery.

Durability-wise, the piston and exhaust valves are slightly modified, and, in the 5-speed transmission, the gear stopper lever is changed to a solid roller from a ball-bearing type.

To make your life a little nicer with the YZ, there’s a new exhaust cam with a six-degree decompression angle change that is intended to make kicking over the bike a little simpler, and the throttle return spring is now softer for a 20-percent reduction in throttle-twist force, which means less work for your right arm.

Both the shock and the YZ’s well-liked KYB Speed-Sensitive System (SSS) fork have slightly firmer settings. The fork also holds 5cc more oil for improved balance.

Access to the air filter is now easier and quicker. The airbox cover bolts have been replaced by quarter-turn Dzus fasteners.

In the looks department, the YZ has new embedded graphics on the tank shrouds and the rims are now black on both the blue and white models. The chain is also gold-colored.

Yamaha gave nothing away in the horsepower department but managed to improve power delivery.

We recently got the chance to spend a quick day at Glen Helen Raceway riding the 2015 Yamaha YZ250F and our first impression was, as we expected, a good one.

The ‘14 mill is without question the best all-around production motor in its class; it is aggressive and has tons of pulling power across the board. Amazingly, the small changes to the ‘15’s motor are noticeable, albeit slightly. The updated mapping gives the new YZ a more refined and smoother delivery and a wee bit meatier pull from mid to top compared to our still fairly fresh 2014 YZ250F. Otherwise, the ’15 motor feels a lot like it did last year but mainly with a little better control and feel.

The YZ250F retains its well-respected KYB SSS fork that now has a slightly stiffer setting.

We definitely noticed the lighter—but not too sensitive—throttle pull. With less resistance, it gives the sensation that the bike lighter in weight. It also helps reduce rider fatigue.

Starting the bike also takes a little less effort.

We were impressed with the ‘14’s suspension and even more so with the ’15’s. Although the difference is subtle, you can feel how it’s slightly stiffer overall now, which our faster test riders favored, though our lighter riders feel that the fork might be a little too stiff out of the box. The initial stroke of the SSS fork, however, is generally plush and offers excellent feel overall, especially mid-stroke. Bottoming resistance is still top notch. The shock works just as well as the fork and performs best with the sag set at 105mm.

It's the same powerful motor as before but with a smoother delivery.

Like last year, the YZ feels light and narrow between your legs and is predictable and easy to maneuver on the track. Frame responds well to rider feedback and the pegs are large and provide plenty of footing. The handlebars are also fully adjustable, adding to the bike’s excellent feel. Brakes are again strong. They are among the best in the business.

In a nutshell, the 2015 Yamaha YZ250F is a slightly improved version of the ’14 YZ. In this case, however, “slightly” is as just good as “majorly” since the YZ250F was already the best in its class. Although Yamaha didn’t make a lot of changes to the ‘15, from what we can tell so far, the changes they did make are indeed all for the better.

Both the blue and white versions of the YZ250F come with black rims

 

By Cycle News Staff

Comments