--The handling on the YZ seems to come under scrutiny for its turning. We have had turning issues with our bike as well. They were easily remedied by playing with the ride height. First by getting the sag setting dialed for the rider, typically between 100-105mm, then on some circumstances by playing with the fork height in the tripleclamp. That is why these bikes are adjustable, you know. There is not one magical setting that everyone settled on but we seemed pretty happy for riders in the 170-190 pound range with closer to 105mm of sag and the stock fork position at all of the tracks we rode. The whole time we were within one click of stock on all the clickers. After that we rarely fiddled with the bike, track-to-track.
--The suspension has a very plush feel and really good control of its stroke. It bottoms only when you'd expect it to and even pro riders were able to push pretty hard on the stock setup. Smaller and lighter riders seemed happiest with less compression damping and more rebound damping to settle the bike and definitely had to play with it more to get happy with the turning. This is one bike that definitely has a zone where it really shines when you dial in your setting. Luckily for most of our riders, that zone is really close to stock.
What's Not:
--Honestly there is very little to complain about outright on this Yamaha. To go straight to the coating wearing off the clutch side cover would tell you how dialed everything else is, so we'll start there. The coating wears off the clutch cover on the first muddy ride!
--Some riders were still able to get less-than-smooth shifting to rear its head. Though definitely better than last year, a few of our testers got a long shift, or a slight reluctance between second and third gear and the overall action is definitely not the best ever when compared to other bikes.
--The muffler is tuned into the package of the bike. Yes, you change that muffler and you are opening a new can of worms and we are pretty sure that a fair amount of the turning issues you hear about with YZ450s comes from the bike having an aggressive low end snap. (Also, the majority of turning complaints come from riders who do not know what setting the sag means.) Yamaha has tuned the bike to run strong with a mechanically restrictive muffler. If you take that off (and we have played with other mufflers and exhaust systems), you will also have to play with your chassis setup, guaranteed. Not to mention the jetting on some of the more free flowing systems. In the past we've had the best luck with the quieter offerings from the aftermarket.
--Since the YZ is so willing to go a gear high, and as a rider you get used to riding it like this, sometimes you can get some hesitation at big throttle openings and low-low RPM. Why do we notice this? Because before there was not a real solution to this, now there is Fuel Injection and you can get away with this kind of throttle wackiness on FI bikes. On the carbureted Yamaha, you notice this slight stumble. Answer: Slip a little clutch or downshift, maybe you are truthfully a gear too high.
What it is:
The 2009 Yamaha YZ450F is a great motocross bike. It is ready to race for all levels of riders and it is doing it with a sensible sound output to help keep tracks with sound issues out of trouble. To top it off the power is easy to use and the bike gets great traction. Matched with excellent suspension, riders savvy with setup can get the bike to do whatever they want it to do, adding the adjustable tripleclamp makes it even more versatile. Overall it is a package that isn't specific to any type or style of rider and seemed to satisfy all of our testers.
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