For the upcoming Supercross and outdoor motocross seasons Suzuki continues to campaign its proven 2014 RM-Z450 ($8699). Sporting nothing more than yellow side panels and a re-flashed computer designed to make the engine easier to start, can Suzuki’s venerable platform still run with the more recently overhauled machines in the 450 class?
Swing a leg over the Yellow bike and you’ll find it’s no featherweight. Glancing at the spec sheet reveals that it weighs 249 pounds with its 1.6 gallon aluminum fuel cell filled to the brim. It certainly feels a bit porky at a standstill—a feeling accentuated when you boot the kickstart lever. Although engineers attempted to make the engine easier to fire, it still takes a strong and well-timed kick to get lit on the first try. Occasionally it takes two, sometimes three tries, along with the use of the right-thumb actuated hot-start lever, if the engine is already warm. The starting procedure certainly isn’t terrible but could be improved.
“It seemed a little hard to start,” confirms our lady tester and three-time X Game gold medalist, Vicki Golden. “It felt like it had a lot of compression kicking through the stroke.”
Despite its hefty feel in motion the RM-Z serves up tremendous agility. Pick a line and the Suzuki complies immediately, tracking exactly where the rider points it. If you’re a rider who has a hard time negotiating ruts than this is the machine for you. Another big plus is the grip served up from the OE–fitted Bridgestone M403/M404 tire combo.
“It handles phenomenally through ruts,” says Golden. “Especially the long ones—you don’t even notice the ruts are there. It just goes right through them.”
(Top) Although the Suzuki is a little porky on the scales with wheels turning it feels much more agile than what the spec chart leads you to believe. (Center) The engine in the RM-Z is responsive and punchy and we love being able to adjust the powerband with its included and easy to change plastic couplers. (Bottom) One of the biggest attributes of the RM-Z’s engine is how smooth it generates power from bottom to top.
You’d think that a bike this agile might be a bit nervous but on a moderately bumpy track it is not. Handling is neutral—never turning more or less than what the rider inputs through the controls. The motorcycle’s ergonomics function well and it is easy to shift your body fore and aft across the seat and the flat radiator shrouds don’t get hung up on your boots or knee braces.
“I feel the ergonomics are really good,” said 5’5” Golden. “I fit me just right. I always prefer something a little bit smaller but I didn’t have a problem with it.”
Introduced on the ’13 machine, the Showa-supplied Single Function Fork splits bump absorption and damping duties between fork legs. The right leg houses the coil spring (1.0 kg/mm—same spring rate as the RM-Z250) with a preload adjuster atop the fork cap allowing for ride height adjustment based on rider weight or handling preference. The left leg houses the damping cartridge and can be fine-tuned via the compression (fork cap) and rebound adjuster (bottom of fork leg).
The new fork offers a distinctly different feel from a conventional dual coil spring or air fork, the main benefit being it is lighter and more responsive to the terrain. With the addition of spring preload adjustment we found that the fork responds best when the spring has tension on it (adding preload) and the compression damping circuit is set in the middle of the range, allowing it to move more freely. Fork action can then be fine-tuned however the damping circuits are sensitive to adjustment with just one click netting a big result.
The gas-charged shock remains conventional in design and retains its 5.7 kg/mm spring rate (compared to the softer 5.5 kg/mm on the RM-Z250) but it works offering excellent chassis control and a good range of adjustment too.
Preload: 5 (Turns in)
Compression: 7 (Turns out)
Low-Speed Compression: 10
High-Speed Compression: 1.75
Power-wise we’re big fans of the way in which the RM-Z’s engine puts power to the dirt. It barks off corners with a smooth but deliberate spread of propulsion from idle to the rev limiter. Throttle response is instant but not overly sensitive making it a fairly non-intimidating 450 to ride. The engine’s powerband can be tailored further using one of two supplied plastic couplers installed underneath the left radiator shroud. Fitting the ‘white’ coupler leans the engine slightly, resulting in punchier and more rev happy engine response. This will benefit aggressive riders or when riding in sand or deep, loamy terrain. Contrarily, vet riders or those that ride on slick hard pack might prefer the ‘grey’ coupler which reduces throttle response slightly and helps maintain rear wheel traction. It’s a great setting for use during a long, 30-plus minute grand prix style race or any other type of competition in which you don’t want the bike’s power to ‘wear you out’. However for normal riding on a groomed track we prefer the stock map.
(Top) With its neutral handling and power characteristics the RM-Z450 is a easy bike to get acclimated to. (Center) The RM-Z’s ergonomics are well thought-out and functioned well for both our testers. (Bottom) We love that Suzuki sticks with Bridgestone’s fantastic M403 and M404 tires as they offer excellent grip and durability.
“The power is phenomenal—every gear—the power is always right there,” she says. “And it’s smooth power. It’s not super aggressive and it just made the bike easy to ride.”
We also appreciate the precise engagement and works-style feel of the yellow bike’s five-speed gearbox. Though clutch lever pull isn’t the lightest, it has a responsive feel which works great during launches or when trying to modulate engine power through tight turns.
RM-Zs have developed a reputation for their strong braking components amongst the Japanese machines and the ’14 version continues to impress. Although the brakes don’t have the lever sensitivity of that pesky Orange brand they are still powerful—you just need to get used to not having a whole lot of brake feel to discover it. The rear brake, however, has a slightly mushy feel—a quality that some riders might appreciate while others won’t.
Despite being the oldest platform in the 450 class the RM-Z is still one heck of a motorcycle. With its sharp handling and versatile motor performance it’s a bike that’s easy to get used to and one that makes you feel like a pro on tight rutty tracks. If Suzuki could improve the settings of the SFF fork and drop a few pounds there’s no doubt that it would have a winner on its hands for years to come.
- Turns on a dime—predictably
- Smooth, strong engine power that is easily tune-able with supplied couplers
- Precise gear engagement with short shift lever throws
- Could weigh less
- SFF fork is tricky to set-up
- Still a bit finicky to start
Bore x Stroke: 96.0mm x 62.1mm
Compression Ratio: 12.5:1
Fuel Delivery: Fuel-injection
Clutch: Wet multi-plate, cable actuation
Front Suspension: Showa Seperate Function (SFF)fork; Six-position preload, nine-position compression and 12-position rebound damping adjustment; 12.2 in. travel
Rear Suspension: Showa gas-charged, 12-position compression, step-less high-speed and 12-position rebound damping adjustment
Front Brake: 240mm disc, double-piston caliper
Rear Brake: 240mm disc, single-piston caliper
Handlebar: Renthal Fatbar
Tires: Bridgestone 80/100-21 M403, 110/90-19 M404
Weight: 249 lbs.
Wheelbase: 58.9 in.
Length: 86.2 in.
Width: 32.7 in.
Ground Clearance: 12.8 in.
Seat Height: 37.6 in.
Fuel Capacity: 1.6 gal.