Will the long overdue 2018 ZUK 450 be worth the wait?
It’s been overdue and talked about for several years but the proof is in the photos, it does exist, a new Suzuki RMZ Four-Fiddy.
The current RMZ450 turns on rails and handles very well…providing the track wis smooth. The chassis works but us stiff and does not absorb bumps well and transfers a tad too much of that back to the rider. Suspension work helps but is not a total fix.
To see Suzuki put an all-new chassis around an updated engine, could be a win win? The key is, were they able to retain the bike’s great turning while allowing the frame to offer a better and less rigid feel?
Key Changes
Increased Engine Performance
Improved Throttle Response with Higher Peak Power
Evolved Traction Management System Helps the Bike Hook Up
Updated Suzuki Holeshot Assist Control (S-HAC) Gets You Out Front
Advanced Cornering Performance
New Frame and Swingarm are Lighter with Excellent Strength
Refined Chassis Dimensions
Improved Coil-spring Fork Provides Great Performance and Easy Tuning
New Showa BFRC Rear Shock
Bridgestone X30 Tires
Improved Braking Performance
Larger Front Brake Increases Stopping Power and Feel
New, Compact Rear Master Cylinder is out of the Way of Mud and Boots
Functional Styling
Aggressive New Styling Blends Function with Suzuki Character
Narrow Cockpit Lets Rider Move with Ease for Maximum Racing Performance
Early reports stated the engine was going to be the same as the current model. The 2018 might have similar dimensions but it looks very much new, especially with new electronics and with what they call a traction management system and three-mode launch control. The head has been updated, intake tract, new throttle body FI injection. The list below is long. What Suzuki will be behind the times with is electric start. Thus far, all of the “new” Japanese motocrossers now feature electric start. Kawasaki, no, but there are no real changes to the 2018 KX450F.
Engine Features
• New 449cc liquid-cooled 4-stroke, 4-valve DOHC engine is the latest incarnation of Suzuki’s proven and reliable, fuel-injected powerplant
• The engine has higher peak horsepower with more torque at lower engine speeds for improved throttle response through the entire rev-range
• The cylinder head intake port shape is changed to tumble flow the fuel/air mixture by 25% to help increase power output.
• A 30% larger air cleaner opening is combined with a more direct air cleaner outlet tube path to the throttle body to increase air flow.
• Advanced fuel-injection system makes for extra-smooth power delivery, high fuel efficiency, and superb reliability.
• The RM-Z450 has a new, Suzuki-unique throttle body design with a relocated fuel injector fed by a new, higher-pressure fuel pump directly sprays fuel at the butterfly valve to improve atomization of the fuel/air charge.
• The new throttle body design eliminates complex control linkage so the rider feels a more direct connection to the engine.
• The intake camshaft profile is changed, including more valve lift that the prior model, increasing power at all engine speeds.
• The compact aluminum cylinder is finished with Suzuki Composite Electrochemical Material (SCEM) coating for durability, light weight and efficient heat transfer.
• The piston’s casting is ungraded to include strengthening ribs near the wrist pin bosses to match component reliability to the higher horsepower.
• Engine starting is simple and efficient due to a long kick starter lever, refined internal gears, larger air cleaner and breather system, plus an automatic decompression system that works precisely and efficiently (eliminating the need for a heavy and costly electric start system).
• The high-flow exhaust system complies with AMA sound regulations.
• New engine protectors help
The chassis is another element that is now has lighter frame and swingarm and is probably more forgiving without wrecking Suzuki’s great handling. The new frame claims to be 1.3 pounds lighter and the subframe is .25 pounds lighter. The subframe/chassis also slimmer overall including the bodywork. Overall the chassis is said to be slimmer for “spirited riding,” whatever that means. Below is the list of chassis features.
2018 Chassis
• The 2018 RM-Z450 features a new frame and swingarm design that continues the Suzuki’s reputation as the best handling motocrossers available.
• The new aluminum-alloy twin-spar frame combines cast and extruded sections to achieve superior front-and-rear weight distribution while balancing strength and weight.
• The new frame is 700 grams (1.32 lbs.) lighter to improve cornering performance and shock absorption while delivering stable handling.
• The new swingarm is assembled with thinner materials for 100 grams (0.25 lbs.) lower weight while cornering performance and handling stability is improved.
• The wheelbase is shorter and the frame head pipe is relocated to produce quick and nimble handling characteristics.
• New hexagonal aluminum rails are used on the sub-frame for lighter weight, a slimmer appearance and easier air-filter service.
• The sub-frame rails are moved inward to slim the bodywork, but are also raised to provide additional space for the larger air cleaner and the advanced BFRC shock absorber.
• Not only is the sub-frame thinner, but the all of the body work is slim to enable the RM-Z450 rider to move freely in the cockpit, especially during spirited riding.
• Inspired by the advanced suspension from the GSX-R1000R Superbike, the RM-Z450 has a new SHOWA Balance Free Rear Cushion (BFRC) shock absorber.
• The BFRC uses a separate, external damping circuit that improves the responsiveness of damping force to deliver excellent traction and better absorption over bumps.
• The fully adjustable BFRC controls damping so well during minute suspension movements that ride comfort is increased at lower speeds while stability is enhanced at higher speeds.
• New generation, improved SHOWA coil spring front fork has larger inner tubes and rod pipes for strength and durability. Front suspension tuning and maintenance is balanced and easy; a great benefit during frequent riding.
• Springs in each fork leg combine with larger, adjustable damping cylinders to deliver better response to the terrain and provide a strong feeling of control to the rider.
These days suspension is always a talking point and another OEM has ditched the air fork and back to a spring fork. The 2018 Zuk 450 will get a similar 49mm Showa spring fork that Honda runs on their 450 crosser. It’s a mass production of the very popular Showa Kit 49mm Spring Fork. Out back Suzuki is breaking some new ground with a new style shock for a production motocrosser. The SHOWA Balance Free Rear Cushion (BFRC) shock absorber, according to Suzuki, is based of the shock from the GSX-R1000 Superbike. It utilizes a separate external dampening circuit that is designed to be more responsive and provides more wheel to the ground traction.
Looking at the Suzuki, it is a NEW motorcycle and many Suzuki fans believe it was well overdue. Good to see Suzuki went all out and made a slew of changes and even introduced some new technology into a production bike. Remember, Suzuki was the first to sell an FI 450 motcrosser, but who remembers that? The 2018 RMZ450 looks promising, especially if they were able to retain the current machines turning ability into a new more forgiving and slimmer chassis. The claimed curb weight of 247 is not feather-light for a kickstart-only motocrosser but like we always say, its how light it feels not always what the scales say. Right now we have to look at photos but in the near future will can tell you exactly if the new spec RMZ450 works in the dirt.
