As always the makers of the fiercest atv’s will continue to evolve to corner the niche markets. Yamaha is no different and has stayed poised to tear into the competition. With the 2009 Yamaha line up comes a new and exciting breed that not only gets the working side of the family moving but for the younger, mild to wild group its as sporty as you can get with racks and four wheel drive.

Getting right into this model we noticed some additional equipment in the front lower part of the Grizzly 550’s frame. This is the comfort adding power steering unit that was first made public on the Grizzly 700. This little device is connected to the handle bars through a torsional bar which reads rider input and translates this back to the on board ECU for just the right amount of assist. Being that the steering is very light at low speed you might wonder how you will control this bear when the throttle is pinned. Not to worry because the dynamics of this steering allows it to fade the assist at higher speeds. This will allow the rider to maintain control and not get the twitchy feeling through the bars at faster speeds. You will most likely find the best use of this new power steering during rocky tight trails or when the differential is locked for supreme traction. It takes a little getting used to but when you realize the benefit you’ll never look back.

Looking at the 700cc sibling Yamaha developed the new engine in this Grizzly 550 and then some changes were made for awesome power for this lower displacement unit. Using this as a starting point the engineers revamped the head on the 558cc Grizzly for improved flow technology and overall performance. Matching the valve and combustion chambers to make a 558cc engine means getting more bottom end power and improved throttle response. Pushing fuel through the Yamaha fuel injection is made possible with the 40mm throttle body. This YFI is good for varying altitudes including 600 to 15,000. This means that where you ride isn’t a problem. Using things like reduction of the overall bore to 92mm, roller rockers, and ceramic composite plating of the cylinder make the engine run smooth and with less friction. If you look back at valve rockers in the past the stock stamped steel rockers created power-robbing friction. By adding roller rockers they not only reduced engine friction but created horsepower just by freeing up the overall system. This means higher rpm’s and a more reliable engine.

As far as the driveline is concerned getting the power to the ground is job one. The transmission or what Yamaha calls it’s Ultra-matic Transmission has became a very reliable design and that’s what you’ll find tucked into the frame on this model as well. The design includes a six-shoe set-up with a one way sprag clutch. This is why the Yamaha grizzly 550 has such a natural feeling engine braking. Keeping a constant tension on the belt the Ultra-matic Transmission will eliminate any lag felt in the throttle to movement relationship. Getting the power to the ground is an easy task for this wild animal as the traditional CVT drive sends the torque down to the wheels through traditional drive shafts. In the past Yamaha owners have experienced trouble with premature CV boot failure due to rocks, branches or the occasional root in the trail. Its bound to happen to all of us sometime. This has also caught the attention of the engineers and for 2009 the boots on these drive shafts are thicker and 200% stronger. The added strength in the A-Arm guards both front and rear and the positioning of them will also reduce the amount of tears or punctures to the CV drive boot as well. If crossing water is your favorite game then Yamaha has you in their sights. The CV enclosure is vented very well with the intake and exhaust snorkels coming right up to the highest point possible for the deep one. This doesn’t mean the new Grizzly 550 is a submarine but it does put your mind at ease for the one that’s deeper than the wheel is tall.

Getting the Yamaha Grizzly started is no problem and getting it up to speed isn’t either but one thing we have yet to cover is the ability to stop this carnivoran species. The brakes on the Grizzly have been revamped to get the most out of the stopping power. With both front and rear braking controls mounted on the bars it has become evident that the right side floorboard mounted foot brake will likely become lonely down there. Riding in the attack position you will find that controlling the Grizzly 550 is as easy as rear brakes on the left and front brakes on the right. Both control each end of the ATV individually. This is a great feature when the unsuspecting corner sneeks up and the message cannot be relayed to the foot before the hand figures it out!

There are a few other features that will make the diehard Grizzly fans happy and even a few that will draw attention away from competing brands. The digital control panel is very well intergrated directly in the riders sight and it includes things such as your speed, odometer reading, trip logs along with the time of day. There are other key elements such as the gear position, and fuel levels. There is even a diagnostic feature that helps the maintenance gear-head in the family figure out what exactly is wrong with the Grizzly should there be a problem. The seat has some additional foam installed for increased comfort and with a 23mm extension on the gate style shift lever, getting this beast into gear will not be an issue.

Overall the all new Grizzly 550 EFI PS is a great way to get into the sport of off road adventures. With a starting price of only $7,799 for the EPS model and $7,099 for the non EPS model there is room for any budget minded consumer that needs reliability and the power of the Yamaha name behind them!