The 2009 Yamaha YZ450F is only slightly modified. The bike was great to begin with, and a few adjustments are nice, but will it be enough to compete against the all-new offerings from Kawasaki and Honda?
Attempting to shake down the minor changes to the 2009 Yamaha YZ450F is all the more difficult when trying not to get mowed down by a full gate of factory pros. Yamaha’s own Josh Hill and Jake Moss were joined by the likes of Ryan Villopoto, Brett Metcalfe, Josh Grant, Jake Weimer and Nico Izzi on our Thursday afternoon test session at Glen Helen. To help hold down the fort against this slew of hired guns, we had our own national pro on hand, the ridiculously fast and ultimate nice guy, Sean Collier. And since the small list of changes to Yamaha’s largest MX weapon is aimed at handling and rider adjustability, we tossed in two other testers of various size and skill.
Most things are still the same, like the usable spread of power dished out through the Tuning Fork’s five-valve, 449cc dual overhead cam motor. Top-end is especially impressive, but we couldn’t find a weak spot anywhere in the powerband. Gearing was close enough for the mountainous layout at GH, but shifting was a highlight this year with a noticeable lack of missed shifts and false neutrals thanks to a beefed up shift fork pin.
A new hydroformed swingarm creates a different feel in the rear end. The new unit is a piece of aluminum art compared to the old with a sleeker design and a noticeable lack of the linkage hole which cleans up the appearance. Many of our testers have found past Yamaha’s to steer heavily with the rear, though an updated front end on the 2008 model helped significantly. Early in the day some of our testers thought the new 450F still had a tendency to step the rear Bridgestone, but some adjustments to the shock’s high-speed compression as the track roughened up helped get things more planted.
“As a first impression, the chassis and handling on the YZ450F resemble the 2008 model with a few exceptions to the rear end,” says regular test monkey, Alvin Zalamea. “I felt like I had to ride the ’09 a bit different than last year’s model with my body positioning more up front over the bars in the attack position. The Yamaha’s straight-line stability still remains great, though; there is no headshake or twitch, which adds confidence in high-speed terrain.”
Also affecting the handling is the all-new top triple clamp which features 20mm of adjustability with the ProTaper handlebars. Off-set bar clamps can be spun to adjust 5mm fore and aft or the entire mounts can be shifted between two sets of holes which are 5mm apart. None of our testers preferred the bars shifted rearward, but placing them in the forward mounts with the rearward (stock) offset was a common change, even for our shortest rider. The extra room was welcome as was the increased bite on the tire, Bridgestone’s Yamaha-specific 403A.
As with the 2008 model, the 48mm speed-sensitive Kayaba fork is super supple. Our slowest rider appreciated the forgiving nature, but riders at the opposite end of the speed spectrum might find it a bit soft. Collier had to tinker with the shock sag settings and mentioned that he might go as far as to modify the chassis give the bike a more balanced feel under deceleration.
Our pro tester, Sean Collier, found the stock setup to be pretty close, but like most super-fast guys, individual tweaking will be required, especially with the Kayaba suspension.
“The 450’s fork is a bit on the soft side and has a tendency to dive upon hard braking coming into corners,” he notes. “It gives the bike a bit of an unbalanced feeling, causing the front end to want to push mid corner. I recommend setting the ride height at around 105 to 108 millimeters and or cutting the subframe five to 10mm.”
Our “normal” testers found the suspension/chassis package suitable and had a more positive feel for the stock setup.
“The whole package gives me confidence,” AZ says, “and Yamaha’s new rear end responded well in dealing with high-speed braking bumps. The rougher the track the better the bike worked.”
An active front end during massive braking can be blamed on the YZ-F’s incredible pinchers. The 250mm wave-style rotor up front is grabbed by a dual-piston caliper. Everyone agrees that the front binder provides exceptional feel, stopping power and resistance to fade, something Glen Helen’s massive hills would have triggered. The 245mm rear unit is nearly as good, but didn’t receive the praise afforded the front.
A lighter rear hub cuts unsprung weight by a claimed half-pound, and the new swingarm is said to knock off another quarter-pound. Overall, Yamaha claims the new 450F weighs 238 pounds with a full tank (1.8 gal), which is probably pretty dang close. The hub also gets a 3mm larger axle (25mm diameter) and switches to a three-bearing arrangement.
Like its little brother, the new clutch lever assembly is added for 10mm of adjustability. A new gold chain, gripper seat cover and black magnesium valve cover add more style along with updated graphics. Even though there isn’t much to crow about as far as technological gadgetry on this MX class bike, the minor changes to the 2009 YZ450F are thoughtful and appreciable by any rider’s standards. By the end of the day our pro rider was mostly comfortable with the handling, and dialed in the settings more to his liking. Though he speaks from a speedy perspective, he has enough faith that the Yammie is a good all-around machine to declare that “this bike will suit any rider.” Somewhere amidst negotiating Glen Helen’s high-speed obstacles and the even faster talent, the rest of our testers came to agree.
Let us know what you think about the 2009 Yamaha YZ450F in the MotoUSA Forum.