Now if the bike was to be fuel injected engineers plans didn’t include any early technology weaknesses so they turned their heads towards GSX-R road racers and inspired their new creation on the fuel injection system found there. A complete success, the new implementation uses a specially created Keihin throttle body and offers greater low-to-mid range grunt. Feeding the engine is done through an internal pump which doesn’t require a battery.
But once the fuel has reached its resting place intervenes yet another factor which makes the engine offer better response down low, through the mid-range, and all the way to the top end: the new design of the combustion chamber. Also, the intake and exhaust valve angle guides have been narrowed and squish areas increased in order to achieve better air and fuel mixing and implicit a bigger bang in the cylinder.
Intake efficiency was taken to a whole new level due to the new intake port angle and cam timing, while the exhaust port and cam timing exploit better the engine’s bangs and gain even more performance.
Very ingeniously, the front fender has a sloped-down shape with the purpose of guiding the air current to the air ducts and offer better cooling. At the rear end, the fender comes with air intakes on each side, a deciding factor for intake effectiveness.
The next, best and natural choice was to mate the redesigned engine to a 5-speed transmission that will get the best out of it. That was also made possible through the link type shifting mechanism.
For 2009, Suzuki decided to go for the semi-dry-sump lubrication system featuring separate oil chambers for the tranny and crankshaft using the tranny as the oil sump. This leaves room for lowering the crankshaft, reducing the engine height and has the rider more in control with a lower center of gravity.
In what concerns the chassis, most pieces are made of aluminum and Suzuki focused on delivering a quick-handling and yet properly-accommodating machine.
They started with the frame which was built from an aluminum alloy making the piece light and yet rigid, perfect for closed-course competitions. The great balance achieved between these two features of the frame also gave it the needed sharpness in what concerns the way it performs.
Showa delivered the suspensions. A fully adjustable cartridge-style front fork does a perfect job in keeping the weight down and absorbing the shock of the bumps. At the rear end there is the same formula only that this time it applies on shock absorber which keeps things in control through tight corners and in bumpy situations. Also, much to do with the rider’s safety feel through corners has the aluminum-alloy swingarm.
Brake rotors were designed to cool easily and not from the water in the mud as they deflect that very easily thanks to their new racy shape.
Also dealing with mud are the footpegs which offer maximum clearance between the mounting bracket and footrest. Well positioned in place, the rider can now concentrate on winning rather than on not falling down the bike.
In 2005 Suzuki introduced the big four-stroke RM model, one that would show a whole different face of competitions, totally different of the two-stroke idea. The bike came with a totally new 449cc liquid-cooled, single-cylinder, four-stroke, DOHC, four-valve engine and a frame that was made out of aluminum instead of steel. A Keihin FCR40MX was the feeding unit for the new powerplant and it has done the job properly in the first years of manufacturing until in 2007 Suzuki announced that fuel injection will come to motocross.
For 2006, the Suzuki engine was slightly retuned for more power output in the low-and-mid rpm range and the intake port was redesigned. Carburetor was reset and the ignition map improved. The extra power allowed slightly taller gearing, smoothing power delivery and redesigned shift forks improve shifting feel. Suzuki also repositioned the hot start lever for ease of operating.
There was the need for more control during tight cornering and over bumps so the steering head was modified and the swingarm had 5 mm taller arms.
2008 brought fuel injection to motocross and all the goodies you’ve read in the intro and the bike sells on as a 2009 model year, being more advanced than any other Suzuki motocrosser before it.
Wherever he’ll be heading, the biggest RM will have to share the success with Honda’s late arrived 2009 CRF450R. Not only the red blast is new as next year’s model, but it relies on the Programmed Fuel Injection (PGM-FI) with 50mm throttle body to induct the fuel into the burning chamber of the liquid-cooled, 449cc, four-stroke motor. This makes the CRF even more powerful than previous model years and a close-ratio five-speed transmission is here to provide a gear for every riding situation. Like every MX bike of this manufacturer, the CRF450R comes with Honda Progressive Steering Damper and one-off racing frame, suspensions and brakes.
Yamaha has also introduced the 2009 motocross lineup, with the YZ450F on top of it. Strongly revised and with a background full of successes, this is definitely among the strongest opponents the RM-Z450 will have to face. Even though it isn’t fuel-injected, the 449cc liquid-cooled, four-stroke, DOHC engine has the advantage of featuring five titanium valves and that is enough to make the Suzuki raise a few question marks.
Kawasaki enters the competition with a totally redesigned engine that has the same characteristics as the Yamaha one, only that it has four valves. What makes it even more threatening for the subject of today’s review is the fact that its motor is also fuel injected and features Keihin throttle body. It seems that the Suzuki -Kawasaki union has yet a strong word on the motocross track as even though any collaboration between the two makers has stopped the plans have remained and, as you can see, results keep on showing.
Suzuki couldn’t leave such a radical revision pass without design changes that would mark the upgrade so it gave the RM-Z450 a new, more aggressive look.
Starting with the front fender, it has the sloped-down shape which is for cooling purposes, but makes the new RM look very stylish and ready to race. At the rear, the air intakes on both sides are for heighten intake efficiency and also stand out.
For 2009, we very much appreciate the way the fender blends in with the number plate, creating a harmonious angry looking thing. That look is being sustained by the side panels which share black and yellow color for an even more compact feel.
The seat is a two-tone color and if you can still spot the rear fender in the clouds of dust, you will surely appreciate its arrow-like design.
Yellow is the color of choice for Suzuki dirt bikes and the RM-Z450 makes no exception. But there are also stylish white number plates and the two-tone seat we’ve just mentioned.
Having worked quite hard at the 2009 RM-Z450, Suzuki gets us motivated to swing a leg over the bike and see what it can do. Well, it is hard to decide on what to start with between the way it handles and the way it accelerates, but these exact qualities set the Suzuki apart from the crowd.
The bike is very quick and response, feels light so it goes around the corners very well, especially with that grippy front end which never managed to lose the front wheel, not to mention the rider. Backed up by the very potent fuel-injected and liquid-cooled four-stroke engine, this machine is a real blast either you’re going out of corners and need that great amount of mid-range grunt or on the straight and over the whoops. The strong and yet smooth motor is easy to get accustomed with and although it doesn’t rev as hard as other 450s, it is a ripper.
What I’ve come to notice is the fact that Suzuki manages to establish the best fast in, fast out strategy as the well engineered chassis requires some heavy leaning and over the tank positioning and that’s pretty much it. As you go out of the corners, the durable clutch engages smoothly, leaving the engine to work its magic on that rear wheel and on the competition.
Shifting is also easy and precise and I must say that I didn’t even reached fifth more than twice as the engine is great fun and the track pretty demanding. In these conditions, the seat and footpegs must have the rider almost glued to them and riding the RM-Z450 makes you indeed feel like one with the machine. The handlebars are at quick reach so the rider is properly accommodated on Suzuki’s prod and joy.
Other units worthy of appreciation are the Showa suspensions. These make landing the easiest thing and bottoming resistance is quite rarely reached. The fully-adjustable cartridge-style front fork means serious business no matter how rough the terrain might be while the new shock absorber keeps the bike stable under hard acceleration (that means always) and at high speeds.
The hot start lever on the side of the handlebars is a great feature and while we’re here, applying the front brake seems like a good idea considering the new waved rotors that the bike gets for 2009. Braking performance is very reassuring both front and rear (you’ll apply both brakes instinctively, anyway) and stopping is fast and confidence inspiring.
Overall, the Suzuki RM-Z450 is a great step forward for the Japanese manufacturer and a great much expected step for dirt fans.
A 2009 Suzuki RM-Z450 comes with a price tag of $7,499. Considering Honda’s $7,599, Yamaha’s $7,399 and Kawasaki’s $7,549, the Suzuki situates on top of our preferences. You do the appreciation and choose from here.
One of the most highly competitive dirt bikes on the market today, the yellow blast has followed an ascended run in its short career until this time and we reckon that it has much to prove yet as it stands for innovation and advancement in a class where development and competition never end. There’s the Suzuki blowing away everything!
Engine and Transmission
Engine: 4-stroke, liquid-cooled, DOHC
Bore Stroke: 96.0 mm (3.780 in) x 62.1 mm (2.445 in)
Compression Ratio: 12.2 : 1
Fuel System: Fuel injection
Lubrication: Semi Dry sump
Ignition: Electronic ignition (CDI)
Transmission: 5-speed constant mesh
Final Drive: D.I.D 520MXV, 114 links
Chassis and Dimensions
Suspension Front: Telescopic, coil spring, oil damped
Suspension Rear: Link type, coil spring, oil damped
Brakes Front: Disc brake
Brakes Rear: Disc brake
Tires Front: 80/100-21
Tires Rear: 110/90-19
Overall Length: 2185 mm (86.0 in)
Overall Width: 830 mm (32.7 in)
Overall Height: 1260 mm (49.6 in)
Seat Height: 955 mm (37.6 in)
Ground Clearance: 350 mm (13.8 in)
Wheelbase: 1480 mm (58.3 in)
Curb Weight: 112 kg (247 lbs)
Fuel Tank Capacity: 6.2 L (1.6/1.4US/Imp gal)