Toying With The Competition: The YZ250F

For the second time in recent years Yamaha has turned the motocross industry upside down, this time with the introduction of the 125cc-class legal YZ250F four-stroke. Yamaha first slapped the competition in the face back in ’98 when it introduced the incredibly successful YZ400F¿which not only won the 250cc National championship that year with Doug Henry aboard, but also sold out before it even hit the dealership floors! The major success of the YZ426F, coupled with superb new YZ125 and YZ250 two-strokes, helped Yamaha dethrone Honda as the number one off-road motorcycle manufacturer in the world.

But back to the bike we’re testing! If the long waiting lists at dealerships around the world are any indication, the YZ250F is yet another stepping stone in Yamaha’s quest to achieve an “untouchable” status in the off-road marketplace. Can you imagine the looks on the top executive’s and engineers’ faces at Honda, Kawasaki, and Suzuki when news of the YZ250F got out? Before any of them could even make a serious run at the YZ426F, Yamaha raised the bar even higher with another high performance, four-stroke MX bike! What could possibly be next? A four-stroke YZ150F to compete in the 80cc class? We wouldn’t be surprised!

Word of the new 250 first reached the TransWorld MX offices in late March, but it wasn’t until the Yamaha Dealer Show a few months later that the factory would confirm its existence. Yamaha of Troy’s Ernesto Fonseca began showing up at Glen Helen’s Thursday practice sessions shortly thereafter, and watching him blow by some of the top motocrossers in the country had our entire staff questioning the fairness of the 250cc four-stroke in the 125cc class. How could a 250cc motor be legal in the 125cc class?

[IMAGE 2]The rule allowing thumpers up to 250cc in the 125cc division has been around since ’97, just like the 250cc-class rule that allows four-strokes up to 550cc.Why on earth would the AMA pass such rules? Basically, the rules were made to encourage EPA-friendly four-stroke engine development amongst the factories, safeguarding the sport’s future in this time of extreme environmental awareness.

Like it or not, it’s our bet that dirty burning two-strokes are running on borrowed time. But why are thumpers allowed extra displacement over their premix-burning counterparts? It’s simple: the extra displacement makes up for the inherent differences between two-stroke and traditional four-stroke engine design¿with traditional being the operative word. Yamaha caught the industry off guard with its highly competitive five-valve motor design, but penalizing the manufacturer for pushing the envelope of four-stroke technology would be even less fair than the original rule itself.


With a four-stroke savvy rider aboard, the YZ250F enjoys some significant advantages on certain tracks, but don’t think that the bike will automatically put you on top of the podium. Fast, choppy, hard-packed tracks are the YZ250F’s forte. On hard-packed surfaces, a two-stroke 125 will light the rear tire up as soon as the motor hits the powerband, but the 250F has very tractable power that allows it to hook up and accelerate on even the slickest of surfaces.

Decompression braking also allows a good four-stroke rider to carry substantially more corner speed through off-camberr and/or slick corners. The comparatively mellow powerband allows you to get on the gas much sooner than a two-stroke, resulting in much quicker lap times if the bike is ridden correctly.

Due to the torque and impressive over-rev of the YZ250F motor, the bike also shines in perfect traction situations. In places that a 125 needs liberal amounts of clutch work to keep it on the pipe, the 250F will pull hard with no clutch work at all! Part of this is due to the torque of the motor, and part is due to the fact that a good four-stroke rider won’t allow the motor to fall under about 10,000 RPM, even in the corners. The YZ250F revs to 13,500 rpms, and that’s where it should be ridden just about all the time. This isn’t your typical slow revving four-stroke¿it demands to be ridden wide open like a two-stroke 125.

The YZ250F does have its weak points: tight tracks or sandy or muddy conditions, to be exact. It’s not that the bike can’t get in and out of tight corners quickly, but the 250F tends to struggle when entering tight corners and in off-throttle situations. Furthermore, while a two-stroke 125 will glide across the top of the sand when you let off of the throttle, the four-stroke¿due to its decompression braking¿will push the front wheel down into the soft surface. In soft sand conditions, the 250F has a heavy, clumsy feel that can wear you out. This same characteristic also surfaces in deep mud.

[IMAGE 3]The YZ250F is about 20 pounds heavier than a 125, and this is its biggest disadvantage on tighter tracks. A 125 can be manhandled in and out of tight corners and, thanks to its snappy powerband, is a bit easier to navigate around supercross-style tracks. Here’s where we contradict ourselves: There’s no question that it takes less effort to get in and out of the tight corners on a 125, but thanks to the high-revving, torquey motor of the YZ250F, it is much easier to get over jumps directly out of corners on the thumper. Where we struggled on a 125 to shift into second or third gear before the takeoff of a jump, we would let the 250F rev its brains out and it would easily get us over any tricky jump section. As a side note, Fonseca told us that he could hit all of the jumps on the gnarly Yamaha SX track from the inside lines, just like Jeremy McGrath does on his two-stroke YZ250.

Because of the YZ250F’s extra weight, Yamaha opted to use the same linkage, swingarm, shock and forks that come on the two-stroke YZ250. This allowed Yamaha to skimp a bit on suspension development for the YZ250F, but lucky for Yamaha (and all of us), the suspension works better on the 250F than it does on the YZ250. The 250F practically glides over choppy, rough, square-edged sections. G-outs and deep whoops are about the YZF’s only downfalls, which is mainly due to the four-stroke’s extra weight.

For average 125cc riders, the stock suspension settings are nearly spot-on, but our testers stiffened the forks up three clicks on compression, and one click on rebound. We added a 1/4 turn of high-speed and two clicks of low speed compression to the shock, and slowed the rebound one click. Faster and heavier racers will want to go to the optional heavy 5.0 spring on the rear and the heavy 0.45 springs in the front.

As much as we hate to admit it, it’s tough to find negative things to write about the YZ250F. Sure, we could pick it apart by saying the side panels are too hard to put backgrounds on, or that the grips are too fat, but let’s face it¿this bike rules! The negative traits that we did list are minor compared to all of the great things about the bike that we were able to come up with. Thanks to the torquey, high-revving motor¿along with the great handling chassis¿the YZ250F is super-easy and unbelievably fun to ride. As far as racing goes, don’t be surprised to see one, if not two, YZ250Fs sporting the number-one plate in 2002. To be blunt, this is the best production bike we have ever ridden.