Suzuki RMX450Z Dirtbike | First Ride

New But Not Enough

Those of us with a taste for dirt have been anticipating Suzuki's off-road 450 for quite some time. Considering the excellence of the yellow brand's recent motocross machines, we were fully expecting to be blown away by the enduro version.

Unfortunately, something went wrong while transforming the RM-Z450 into the RMX450Z. After a few hundred miles on the new bike, a few things became clear. As sold, the four-stroke single feels corked-up and suffers from fueling foibles, while the fork and shock are lightly sprung and heavily damped, resulting in peculiar, harsh handling.

The enduro is fed by the same Keihin fuel-injection system as the 'crosser, yet runs strangely, popping and fizzling down low. Lean fueling coupled with a light flywheel make stalling a constant problem. Add to that a range of clutch engagement so wide that it makes complete disengagement difficult, and you've got a recipe for frustration. Thankfully the RMX is equipped with an electric starter, so you won't wear out your kicking leg.

Once things are spinning the fueling cleans up, and the engine pleases with the same long-pulling power as its progenitor. Despite the bunged-up exhaust, the bike has a healthy bottom end and robust midrange. On the trail, the RMX has a light feel similar to that of the RM-Z, but harsh damping causes the front end to deflect. The mismatched suspension creates a bike that's too softly sprung to be ridden aggressively over jumps yet too stiffly valved to hit rocks, roots, logs and other trail obstacles. Ride the bike slowly on a tight trail and it will stall. Rev it out on a fast fire road and the front wheel gets flighty.

The one range in which the RMX shines is at 20-40 mph. Here, the suspension starts to feel active and there is enough momentum to overcome deflection issues. The engine is in its happy place with plenty of power above and below. If that's the type of riding you do most, then you're in luck. Too bad the 1.6-gallon fuel tank is only good for about 45 miles.

The RMX450Z might not be the best 450cc trailbike we've ridden this year, but it is the only new one. Our hat's off to Suzuki for unveiling a fresh new dirtbike while the other Japanese manufacturers are cowering in the corner. The RMX has its weaknesses, but considering how much RMZ DNA it received, you know it has its strengths, too.


Price $8399
Engine type l-c single
Valve train DOHC, 4v
Displacement 449cc
Transmission 5-speed
Frame Aluminum twin-spar
Front suspension 47mm Showa 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, 250mm disc
Rear brake Nissin one-piston caliper, 240mm disc
Front tire 80/100-21
Rear tire 110/100-18
Seat height 37.6 in.
Wheelbase 58.3 in.
Fuel capacity 1.6 gal.
Claimed dry weight 262 lbs.

Verdict 3 out of 5 stars
There's a great bike in there somewhere, but no motorcycle should need this much work.

Suzuki RMX450Z Motorcycle

** They say: ** "A hard-core motocrosser for the trail."
We say: "Maybe the soft-core version would be less offensive?"
A lot of RM-Z450 motocrosser went into the RMX450Z enduro, unfortunately including the tiny fuel tank. Different cams and fuel-injection mapping are the major engine changes.