2012 Suzuki RM-Z450 | Dirt

Object of Desire

If you could get an off-the-record response from professional motocross and supercross racers during the 2011 season, most would have agreed that the factory Suzuki RM-Z450 was the best bike out there. Despite being one of the smaller members of the Big Four Japanese manufacturers, the yellow team still threw down a whooping with regularity.

With such satisfactory performance, Suzuki has left the RM-Z450 essentially unchanged for 2012. New graphics, a red seat top and minor suspension adjustments are the only real changes. While it’s always exciting to see new models come with fresh technology and performance-enhancing tweaks, we don’t fault Suzuki for sticking with what it had. After all, the bike feels right, rides right and has more than proven its mettle on the racetrack.

To start with, the RM’s riding position is perfect for average-sized riders, although anyone taller than 6 feet may find it cramped. The bike feels slim between your knees, the handlebar bend is spot-on and the controls have just the right amount of resistance. When it comes time to make some noise and throw dirt, the exhaust note is reasonable, and the fuel-injection is perfect. The RM-Z comes with two plugs to snap into the wiring harness to either lean out or richen the fuel curve, but after trying the alternatives we decided the stock plug is best. In stock trim, the RM-Z is pleasantly smooth and controllable while offering a muscular bottom end. Power builds with revs, and the motor shines in the midrange.

Revving the engine moves things along nicely, but the power doesn’t get crazy near redline. It’s always tractable and easy to manage. The five-speed transmission is nicely spaced for the power, and shifting action is crisp and consistent and requires little thought. Handling is light and quick, and the 450 changes direction easily. When this basic platform was new in 2008, it was criticized as being somewhat nervous, but revised damping at both ends has remedied this issue. We wouldn’t call the suspension plush, but it works very well and resists bottoming on all but the biggest hits.

Some riders applauded the addition of some red to the color scheme. There are some very nice features on the bike, but none are as trick as the aluminum fuel tank. Suzuki’s reasoning behind the metal tank was added protection for the fuel pump, but we just think it looks trick!

No single aspect of the RM-Z450 is mind-blowing. All of the bike's characteristics are good, but what makes it shine is how well everything works together. If the power were more violent, perhaps the suspension and handling wouldn't be so confidence-inspiring. And maybe if the bike didn't turn so well, it would feel heavier. Fortunately, Suzuki didn't go crazy with any single facet of the bike, but instead was relentless in making a machine with systems that work together in harmony. The result is a highly functional motocrosser that's as relevant and competent as ever.

2012 Suzuki RM-Z250

If not for different colored numberplates, it would be difficult to tell the 2012 Suzuki RM-Z250 from its 450cc sibling. They both have premium Showa suspension, electronic fuel-injection and an aluminum fuel tank. The 250 and 450 even share similar power characteristics.

The smaller Suzuki pulls remarkably well from low rpm, and has a fat midrange where it likes to do business. It likes to rev and makes the lion’s share of its power up top, but unlike most 250s it’s not necessary to spin it to access the power. Riders stepping off of 450s had no problem adapting, and within a lap most found they could clear all the same jumps as on the bigger bike.

Throttle response is flawless, as any EFI system should be. The engine never hiccups or hesitates regardless of rider habits or track conditions. Starting wasn’t always consistent, however, and became more difficult as the air filter got dirty.

Where the 250 and 450 differ is in handling. The smaller bike is light, and feels that way in the air and in corners. Heavier, faster riders found the fork bottomed more than they liked, and going stiffer on the compression settings made the ride harsh over stutter-bumps without greatly improving bottoming. A small problem, but one aspiring Pros should be aware of. For the rest of us, this is a great 250cc four-stroke MXer that is fast, nimble, effective and, most of all, fun!


Aesthetic and minor suspension tweaks improve the existing RM-Z450 platform.
Honda CRF450R, Husqvarna TC449, Kawasaki KX450F, KTM 450 SX-F, Yamaha YZ450F.

Price $8399
Engine type l-c single
Displacement 449cc
Valve train DOHC, 4v
Bore x stroke 96.0 x 62.1mm
Compression ratio 12.5:1
Fuel system EFI
Clutch Wet, multi-plate
Transmission 5-speed
Claimed horsepower na
Claimed torque na
Frame Aluminum twin-spar
Front suspension Showa 47mm fork with adjustable compression and rebound damping
Rear suspension Showa shock with adjustable spring preload, high/low-speed compression and rebound damping
Front brake Nissin two-piston caliper, 240mm disc
Rear brake Nissin one-piston caliper, 240mm disc
Front tire 80/100-21 Bridgestone M403
Rear tire 110/90-19 Bridgestone M404
Rake/trail na
Seat height 37.6 in.
Wheelbase 58.9 in.
Fuel capacity 1.6 gal.
Claimed curb weight 249 lbs.
Colors Yellow
Available Now
Warranty na
Contact American Suzuki P.O. Box 1100 Brea, CA 92822 www.suzukicycles.com

VERDICT: 4 out of 5 stars.

**Largely unchanged, but still a big performer. **

They say: "World-class performance."
We say: "The results speak for themselves."
Need to change fueling to compliment a new pipe? Riders can alter the RM-Z450’s fuel curve by inserting a jumper plug in the wiring loom behind the front numberplate.