2018 SUZUKI RM-Z450: FULL TEST

Okay, “all new” might be pushing it a little, but the 2018 Suzuki RM-Z450 has significant changes internally and externally. Since getting fuel injection and a slight styling update back in 2008, the RM-Z450 has seen little to no changes in the styling department. In 2015 Suzuki made changes to the frame rigidity, equipped the bike with air forks and introduced the world to its S-HAC launch control system. Most people didn’t give the bike a second thought, because it looked so similar to the 2010 model. No one will make that mistake in 2018. The bike looks nothing like previous models and has updates to just about every category.kay, “all new” might be pushing it a little, but the 2018 Suzuki RM-Z450 has significant changes internally and externally. Since getting fuel injection and a slight styling update back in 2008, the RM-Z450 has seen little to no changes in the styling department. In 2015 Suzuki made changes to the frame rigidity, equipped the bike with air forks and introduced the world to its S-HAC launch control system. Most people didn’t give the bike a second thought, because it looked so similar to the 2010 model. No one will make that mistake in 2018. The bike looks nothing like previous models and has updates to just about every category.

POWERPLANT

The engine received targeted changes but nothing mind-blowing. It’s still a 449cc, liquid-cooled, four-valve, dual-overhead-cam engine equipped with fuel injection. The intake cam features a higher lift, and the cylinder intake port shape is changed to help mix the air and fuel for more efficient combustion. Piston casting is upgraded to include strengthening ribs near the wrist-pin bosses for durability. Suzuki also upgraded the entire intake system. The air-cleaner opening is 30 percent larger, and the intake boot features a more direct design for increased airflow into the throttle body. The 2018 RM-Z450 has a brand-new, unique-to-Suzuki throttle-body design with the fuel injector located on the bottom and fuel being fed by a new, higher-pressure fuel pump spraying fuel directly at the butterfly valve to improve atomization of air and fuel. All these changes were made to increase peak horsepower, improve throttle response down low and provide a stronger pull through the midrange. The Electronic Control Module (ECM) has a faster traction control management system for 2018 that helps fine-tune the engine output to deliver the best traction in all riding conditions. Suzuki Holeshot Assist Control (S-HAC), commonly referred to as “launch control,” returns on the 450 motocross model. S-HAC is similar to other manufacturers’ launch control systems in Mode-A, where it alters ignition timing to reduce wheelspin for a smoother delivery. Where S-HAC differs is Mode-B, delivering a more aggressive power for stronger acceleration. It turns off automatically after 4.5 seconds or when the rider shifts into fourth gear.

 

CHASSIS

The 2018 RM-Z450 features an all-new aluminum-alloy twin-spar frame. Suzuki has combined cast and extruded sections to achieve balanced front and rear weight distribution. The new main frame is just under 1 1/2 pounds lighter than the 2017 version. Made of thinner material, the new swingarm is 1/4-pound lighter and is designed to work with the flex characteristics of the new frame and subframe. The aluminum subframe rails have been moved inward to slim the bodywork, and also raised to allow more space for the larger air cleaner. They also feature a lighter hexagonal shape. Suzuki has introduced all-new Showa suspension components for 2018. Up front, the Triple Air fork has been replaced with a new-generation Showa coil-spring version that has larger inner tubes and rod pipes. With springs in both legs now, Showa has also incorporated the use of larger adjustable-damping cylinders for better handling. Incorporating technology from road racing, the RM-Z450 is now equipped with a Showa Balance-Free Rear Cushion (BFRC) rear shock. The BFRC uses a separate external damping circuit to improve the responsiveness in all types of conditions. As with the fork, this is the first time we have seen this component on a production Suzuki motocross model. Suzuki has also redesigned all the bodywork for 2018, giving this machine a much-needed facelift. The new styling has a much more aggressive look, with Suzuki’s signature yellow plastics incorporating blue into the scheme. It still has anodized black accent pieces and reinforced black rims. A new plastic tank replaces the aluminum model and is now slightly larger (holding 1.7 gallons of fuel) and a 1/2 pound lighter. The front brakes have been upgraded with a larger 270mm rotor, and the rear master cylinder was redesigned to tuck in tighter to the frame. The tires have also been updated for 2018 with Bridgestone Battlecross X30 models.

THE VERDICT

Suzuki faithful, don’t worry; it still has a familiar feel. We were actually surprised by how familiar it felt. The engine performance is improved across the entire power curve. The performance gains are similar to what an aftermarket exhaust and intake system would do for the 2017 model. We are definitely disappointed by the lack of an electric start. Hopefully Suzuki knows how important this feature is becoming to consumers. The new Showa spring fork has good, predictable action but was on the soft side for most test riders. We went in a couple clicks on compression—any more and it got a little harsh-feeling. We also slid the forks down in the clamps, making them close to flush, and slowed the rebound down for better overall balance. We recommend that faster riders or those weighing in the 200-pound range go up one spring rate. The Showa BFRC shock has a very busy feel and is sensitive to sag. Anything less than 104mm and test riders complained of a stinkbug feel. We found most riders were happy with around 105–108mm of sag. We also slowed the action down going in on rebound clickers. The nice thing about the new shock is that you can actually feel major differences with just a few clicker adjustments. Overall, the bike feels slimmer and slightly easier to maneuver, but is still heavier and bulkier than other bikes in its class. We like that Suzuki has finally updated the RM-Z450. All the changes are steps in the right direction and do not change the fact that Suzukis are still some of the best-cornering machines in the 450cc class.

HITS
• All-new aggressive styling
• Suspension components
• Increased engine performance
• Great cornering characteristics

MISSES
• Heavy
• No electric start
• Lacks adjustability

 

2018 SUZUKI RM-Z450
Engine type … 4-stroke, liquid-cooled,  single-cylinder, DOHC
Displacement … 449cc,
Bore & stroke … 96.0mm x 62.1mm
Fuel delivery … EFI
Fuel tank capacity … 1.7 gal
Lighting coil … No
Spark arrester … No
EPA legal … No
Running weight, no fuel … 240 lb.
Wheelbase … 1480mm (58.3″)
Ground clearance … 325mm (12.8″)
Seat height … 955mm (37.6″)
Tire size & type:
Front … 80/100-21 X30 Bridgestone
Rear … 110/90-19 X30 Bridgestone
Suspension:
Front … Inverted telescopic, coil spring, oil-damped
Rear … Link type, coil spring, oil-damped
Country of origin … Japan
Suggested retail price … $8899
Manufacturer … www.suzukicycles.com