HITS:

-Improved turning prowess

-Better low-end pull and throttle response

-Excellent suspension

-Tougher, longer lasting graphics

-Good brakes

-Pro Taper handlebars

MISSES:

-Black engine cases look worn out quickly

-Turning still not as precise as other bikes

-Like always the blue plastic tends to look a little worn out

            When Yamaha first went to an aluminum chassis a few years ago, it was met with some mixed reviews. Some claimed it just didn’t turn that great, while other raved about the sharp handling and agile turning prowess. After two years, though, Yamaha has decided that it is time for some changes, and for 2008 the big YZF received some refinements to both the chassis and motor that Yamaha hopes will help it move ahead in the ever-important four-stroke wars. In fact, over the past few months, the Yamaha Factory team has actually been running the ’08 chassis with great success. Grant Langston has won numerous races aboard it and just recently the championship, while his younger teammate Josh Hill has had a few top-five finishes aboard the bike. Needless to say, they must be doing something right.

            Like we mentioned, there were some pretty significant changes done to the chassis, which is where we will begin. The majority of the improvements were centered around the steering head and steering stem. Both were shortened 5mm to allow for enhanced handling on nearly any track condition. The forks also received a new outer fork tube and revised internals for improved dampening and a much smoother ride. While in the back of the bike, the linkage ratio was revised to help further complement the different steering head and front fork action. As for the engine, Yamaha made a few minor adjustments to the intake ports as well as exhaust cams to help improve low-end torque and throttle response at the low- to mid-rpm range. And like the YZ250F that we tested last month, the 450 also received black engine cases. Perhaps one of the most noticeable changes is the exhaust system, which is all-new for ’08, and features a drastically shorter and lighter muffler that despite what you might think, helps to reduce noise. The new wider diameter titanium header pipe also helps to improve power of the big bike and compliments the new muffler nicely. Other notable changes done to the bike include a new lighter YZ250F-inspired front caliper, which helps to reduce un-sprung weight and improve suspension action. Also, like the 250f, the 450 received new Dunlop tires, and wider footpegs. As the cherry on top, the YZF also comes standard with high quality Pro Taper bars.

            Last year, we liked the YZ450F, however, in our opinion there were a few things that needed to be fix in order for it to step towards the front of the ultra-competitive 450cc four-stroke class. Over the last couple years, the big YZF had a little trouble in the turns. It wouldn’t necessarily corner horribly; it just wanted to push slightly. For 2008, the bike is much better. The improvements done to the chassis are noticeable, and for the most part improve the bike’s cornering abilities. Unlike how we felt about the turning characteristics of the YZ450F in previous years, we have never had much to complain about with the suspension, and this year’s 450 is more of the same. We rode the bike at the jumpy, rutty, and sometimes rough Perris Raceway in Southern California, and we never had much to complain about, as it handled nearly anything that we could throw at it. We did mess with the clickers slightly, but ultimately the changes that we did make didn’t amount to much more than simple rider preference. As for the engine, the old YZ450F needed a little help with low-end pull and throttle response—it just didn’t have much of a hit. This year, the bike has that, but not too much, as Yamaha has managed to give the bike more low-end grunt while still keeping it easy to ride. This year’s YZ450F still doesn’t have rip-your-arms-off power, but it does have enough to get you into trouble if you’re not careful. Moving onto the new brakes, bringing the bike to a stop isn’t a problem, and despite the smaller, lighter front brake system, we didn’t experience any braking action that was less than what we expected from Yamaha. Finally, as a small side note, even though we haven’t had much time on the bike yet, we can tell you that the black engine cases—while they do look cool—don’t last very long. And after only one day of riding, the black was left severely scratched.

CONCLUSION

            After getting some time on the new YZ450F it’s easy to see why Langston and Hill have been doing so well with the new chassis underneath them. The bike is an improvement over previous years in both the handling and engine departments, and as a whole, the small refinements definitely add up and make a difference throughout the entire bike.

SPECS:

Engine Type                   449cc liquid-cooled DOHC 4-Stroke 5 titanium valves

Bore x Stroke                  95.0 x 63.4mm

Compression Ratio          12.3:1

Carburetion                     FCR-MX39 X 1

Ignition                           CDI

Transmission                  Constant-mesh 5-speed; multiplate wet clutch

Suspension/Front            Speed-Sensitive System inverted fork; fully adjustable, 11.8-inch travel

Suspension/Rear             Fully adjustable single shock; 12.3-inch travel

Brake/Front                     Hydraulic single disc brake, 250mm

Brake/Rear                      Hydraulic single disc brake, 245mm

Tire/Front                        80/100-19-51M

Tire/Rear                         120/80-19-62M

L x W x H                       86.4, 32.5, 51.4 inches

Seat Height                      38.9 inches

Wheelbase                       58.8 inches

Ground Clearance            14.7 inches

Fuel Capacity                   1.8 gallons

Color                                Team Yamaha blue/white; white/red

Price                                 $7,099 (blue/white); $7,199 (white/red)