2010 Yamaha YZ250F First Ride

JC Hilderbrand | July 27, 2009
2010 Yamaha YZ250F Motorcycle Review
Riding the 2010 Yamaha YZ250F at Washougal MX Park proved to be a terrific match. The updated YZ-F is a very good machine – without succumbing to the fuel-injection craze.

There are times when even our best efforts at professional integrity falls to pieces. Usually these are our worst moments, but for a short time on the north side of the Washington/Oregon border, it was just the opposite. An overcast morning on our final day of riding left the heavily watered Washougal Motocross Park to fully soak, and we spent the better part of the early hours shooting photos and spinning laps through the deeply disced soil on the 2010 Yamaha YZ250F. As lunch neared, the majority of journalists had changed clothes and were departing to catch their flights, leaving the track mostly empty. As we ate, the sun broke through fully and flooded the scenic facility. It was the best condition the track had been in for two days, but every journalistic pursuit disappeared and I thought about nothing except hitting my lines on the best laps of motocross I’ve experienced.

So I ditched my testing duties for a few minutes, sue me. The fact of the matter is that the 2010 YZ250F was so much fun to ride and the track was so immaculate that for the final outing or two, I didn’t care one bit about keeping notes, just the pure fun of doing what we love. I had already spent a full day and a half trying to sort out the new YZ-F, and by that time it was clear enough that the ’10 version is much improved and vastly different from the 2009 offering. Yamaha claims to have sold over 60,000 YZ250F machines here in America since it was introduced in 2001. That number is only going to get bigger once the public gets a chance to check out the 2010 bike.

2010 Yamaha YZ250F Motorcycle Review2010 Yamaha YZ250F Motorcycle Review2010 Yamaha YZ250F Motorcycle Review
The bi-lateral beam chassis makes all the difference with the 2010 YZ250F.

Most notable is the new bi-lateral aluminum chassis. This twin-spar design is much like the rest of the Japanese bikes, but the frame spars are very small. Yamaha claims that the vertical rigidity is similar to the ’09, but twisting and horizontal rigidity are much increased. With morning and noon track prep, we never saw any bumps on the Washougal track, which made for a difficult time feeling out the chassis and suspension. However, we were able tell that the 27.5 degrees of rake and extra 3mm of trail combine with a relocated steering head pipe to make a better-handling machine. The steering head is 12mm lower and 7mm rearward compared to ’09. This brings more weight to the front end and the 250F provides more feedback to the rider and better bite – both of which were appreciated on Washougal’s notoriously deceiving dirt. Since the chassis is more cramped, the radiators were forced back towards the rider as well. To keep the midsection from bulging, the radiators were made thinner from side to side, but fatter front to back to keep the same capacity. An additional mounting point was added as well.

With the bi-lateral beam design, engineers no longer have to wrap the fuel tank around a backbone. The 1.7-gallon tank is now down inside the spars which helps lower the center of gravity and adds to the Yamaha’s nimble attitude. This bike definitely likes to turn sharply, and, taking into consideration the smooth track conditions, it still feels very stable. There was one square hole on the track and it was in a sweeping right-hander that led up the hill in a to a fourth-gear step-up. We hit that thing lap after lap and the bike never got out of control, but we’ll be looking for nastier conditions in future testing. Light handling takes less effort, and that’s what Yamaha engineers wanted to provide each and every YZ-F owner.

“We tried to focus on making this bike the fastest for an entire race,” emphasizes Product Planning Manager, Derek Brooks.

With that, the bike is supposed to be thinner this year, but it didn’t feel that way to us. The YZ-F definitely has a better rider layout and is more compact, but thinner never really came to mind – not fatter, just not thinner. A flatter seat makes getting around very easy and the foam actually seems a little wider throughout, but very comfortable. Like last year, the four optional handlebar placements are a nice way to tailor the fit, and with the steering head farther back this year, it’s more needed. For a 5’11” frame, we liked the bars in the Number 3 position (forward post holes, rear off-set clamp position). The bar mounts are 5mm taller, as are the footpegs. We tend to like small-feeling motocross bikes, and the Yamaha falls into that category with a cockpit not unlike a Honda. Gone is the long-and-low sensation.

Known for its forgiving Kayaba suspension, Yamaha wanted to keep its reputation as one of the most comfortable machines. The speed-sensitive KYB fork is updated with a new surface treatment on the piston rod, revised internal damping settings and different fork seals. There really isn’t much to talk about here. Overall the front end works very well. Without any hard impacts to speak of, we softened the front compression clickers two clicks and left it alone the rest of the time.

2010 Yamaha YZ250F Motorcycle Review
The Kayaba suspension still rides very nice, but then again, anything would have on the immaculate Washougal track.

Out back is a new KYB shock, and this piece has more of an active role in the new model changes. Internal specs are redone, of course, but the biggest change is that the spring position is 30mm lower than previously. This was a direct result of a new air intake tract which we’ll get to in a second. The shock is adjustable for high/low-speed compression, rebound and preload. Our settings were at 101mm preload and we eventually found that backing out the high-speed compression a bit helped the rear end squat a little more and let the bike track straighter. We also noticed better traction on the rear end, especially when trying to seat bounce into the whoops (which were really a long set of doubles).

Yamaha managed to boost the power but still retain some of that usable, non-fatiguing rider-friendly delivery we’ve come to expect from blue motocrossers. Much of this comes from the air delivery already mentioned. The air filter is moved 10mm to the left to straighten the intake boot (which has more room thanks to the lower shock spring). Faster, smoother air intake and a new venturi-shaped Keihin FCR MX37 carburetor call for more fuel, so the jetting has been richened. The main jet jumped from 178 to 180, pilot from 42 to 45, with a richer needle and an extra quarter-turn on the fuel screw. Valve spring retainers are now aluminum for a 30% weight reduction which leads to less spring load and lighter spring pressure. A new D-shape exhaust port helps suck out the spent exhaust and the motor as a whole breathes better, revs faster and produces more pop – but only the good kind. Our test bike backfired just once in two days.

2010 Yamaha YZ250F Motorcycle Review
Riding a YZ250F around the outside edge of a berm is completely optional. It has the handling and motor grunt to work the inside just as well, if not better.

Grunt out of corners is the best improvement, but honestly the entire powerband is more effective and fun. The Yamaha used to scream its lungs out but not really generate any over-rev power, but that’s changed this year with additional pull on top. Whether torquing around or revving the beans out of the 13.5:1 compression engine, the exhaust note is pleasant. The mid-pipe steps from 45mm to 50.8mm and the muffler is 50mm longer. However, the muffler core diameter has cinched down from 42.7mm to 41.3mm, and the space between core perforations jumped from 4mm to 5mm which smoothes the outlet of gas. New ignition mapping is set for the updated motor characteristics.

Tucking the motor into the new frame called for new mount points so it now has one on each side of the head rather than a single located in the middle. A new oil sight window is now located on the ignition cover rather than the crankcase putting it up higher. It provides a view into what is now 100cc less capacity thanks to a slimmer oil tank. Internal ratios for third and fourth gears are a tad taller equating to roughly half a tooth on the rear sprocket.

Protecting the mill is a new skidplate. We like the extra burliness of aluminum, but there’s no denying that it can be a problem if it bends in the wrong spot. Plastic bends back, and it also doesn’t interfere with the rigidity of the chassis. Yamaha cites the latter as a main reason for swapping to a new single-piece plastic unit. The new version has less material up around the water pump, but it provides better coverage for the frame rails.

2010 Yamaha YZ250F Motorcycle Review
New bodywork is angular, sleek and basically awesome. We never had any issues with the more compact layout and love the way this new version looks. The white/red option is especially nice, plus we like how the light plastic shows less wear over time.

Our major complaint about the Yamaha in years past seemed like an illogical grievance until you sampled the bike. The YZ250F has been a great all-around performer, but it lacked character, pizzazz, wow-factor – whatever. It has always been something of a plain-Jane. That’s different for 2010, and we couldn’t be happier. Yamaha finally got with the styling program and reshaped the bodywork for an aggressive figure. A KTM-ish front fender, Husky radiator shrouds (which never caught any boots) and a stinger rear fender combine with the minuscule twin frame spars to give the Yamaha dirt bike a very unique appearance. Engineers also put some giddy-up in the motor which is now lively straight off the bottom, and though it doesn’t feel like it revs further, it’s actually doing something in the upper RPM. Plus, the thing corners like a madman, so there’s plenty of character in the 2010 YZ250F.

Yamaha likes to take care of its YZ-F customers with things like a 30-day warranty, 13 million dollars of contingency, a full microfiche catalog and online owner’s manuals, not to mention a full line of GYTR parts (though we don’t know why most of those “better” parts aren’t already on production bikes). Putting its bike in the best light is what manufacturers’ media relations people get paid to do, and Yamaha might prove to have done the best job of it this year. There wasn’t a single thing we didn’t like during our ride, which makes us extra hungry for another shot at the bike with other brands on hand for comparison and some tracks that are in less than perfect shape. As it was, the sample was enough to show that Yamaha has definitely succeeded in the primary objective – making the 2010 YZ250F better than the previous model – and by sizeable margins.

JC Hilderbrand

Off-Road Editor| Articles | Hilde is holding down the fort at MotoUSA’s Southern Oregon HQ. With world-class dirt bike and ATV trails just minutes away, the hardest part is getting him to focus on the keyboard. Two wheels or four, it doesn’t matter to our Off-Road Editor so long as it goes like hell in the dirt.