Ryan Nitzen | October 22, 2023
How does the 2024 Suzuki RM-Z450 production bike stack up against Ken Roczen’s Progressive/Ecstar Suzuki? We got the chance to find out.
Ken Roczen’s “factory” Suzuki RM-Z450 is surprisingly easy to ride, much of which has to do with much-improved suspension.
Photography by Nitzen and Jesse Ziegler
Riding a factory bike is something we all dream about. Getting the opportunity to do so is a different story, but we got that opportunity just a few short days after the SuperMotocross finale in Los Angeles, California. Suzuki gave us the chance to ride Ken Roczen’s Progressive/Ecstar Suzuki race bike at Fox Raceway, located an hour-plus drive south of the LA Coliseum. And, to make things even more interesting, we got to compare it back-to-back with the 2024 Suzuki RM-Z450 production bike. Well, sort of production.
Order now and your 2024 Suzuki RM-Z450 will look like this. Even after all these years, the RM-Z is still an eye-catcher.
RM Army
As you probably know by now, the 2024 Suzuki RM-Z450 is like it was—again. It hasn’t changed since 2018, when it got its last major redo. Unfortunately, it wasn’t major enough, with Suzuki electing not to give it electric starting or putting it on a diet. Still, the RM-Z450 has a lot going for it, especially now that Suzuki has partnered with Pro Circuit as part of Suzuki’s RM Army Edition program. Order a 2024 RM-Z450 before the end of the year, and your Suzuki will be delivered with a full Pro Circuit exhaust system, complete with a carbon tip, and modified engine mapping, at no extra charge. (The RM-Z450 is already approximately $600-$1000 less expensive than most of its competitors, so Suzuki is dangling a pretty juicy carrot in front of you.) You’ll also get a full graphics kit to make it even juicier.
For this comparison, we rode the RM Army-kitted RM-Z450 with the PC exhaust system installed.
I’m no stranger to the RM-Z450, so it was easy for me to feel the difference between the RM Army bike and the stocker. The throttle is more responsive, and the power is throatier and cleaner throughout the rev range. A stock RM-Z feels sluggish in certain areas, like when you wick the throttle midway through a loamy corner. The PC exhaust system makes the RM-Z’s power come alive from top to bottom while still retaining its overall manageability, which is something the RM-Z450 is well-known for. The motor still feels extremely controllable but with more power across the board. No wonder people fork out large sums of money for aftermarket exhaust systems, but with the RM Army bike, it’s free—for now.
Roczen’s bike is tuned for comfort.
Unfortunately, a new exhaust system and graphics don’t do anything about the RM-Z450’s ongoing suspension woes. Since 2018, the RM-Z’s suspension has been unbalanced from the production line, with an overly stiff front end and a soft rear shock. On a deep and loamy track like Fox Raceway, it’s hard to get the forks to engage, so you can’t trust what the front end is going to do all the time. The rear end is soft, but at least it works well enough, and it’s more predictable. Overall, the Suzuki feels choppered out, and it pitches forward and back while in motion more than I like. The bike is still a sharp-handling machine and easy to maneuver, which we like, but it’s missing that much-needed balance.
The production Suzuki RM-Z450 still has its strong points. Turning is one of them.
Roczen’s Bike
Eventually, I moved over to Roczen’s bike, which still had dirt caked on it from the LA race. He runs an air fork versus the standard spring fork, and for our day at Fox Raceway, the Suzuki crew chose to go with the same settings that he used at the Chicagoland SMX race. Roczen’s been adamant about suspension all year and found some extra comfort with a new suspension tuner, Active Ride. Visually, it’s hard to tell the difference between Roczen’s fork and the stocker because there are no special coatings or flashy colors to be found. Only the trick fork caps with their air valves give it away.
One thing I noticed right away was the hot start button on the left handlebar; remember those? Just in case you forgot, since the Suzuki is still kickstart operated, the hot-start button acts as a choke, but instead of injecting more fuel into the cylinder when cold, it injects cool air into the cylinder to assist in kickstarting a hot motor. Stock triple clamps, a recessed kill switch, and standard-issue Renthal Twinwall bars complete Roczen’s cockpit.
The RM Army Edition comes fitted with a complete Pro Circuit exhaust system.
The engine and mapping are mainly handled by the wizards at Twisted Development. It’s no secret that Kenny likes an ultra-smooth power delivery, so the Twisted crew checked that box. Team sponsors like JE Pistons and Hinson Racing take care of the other major internals, while custom engine hangers hold the powerplant in place. Beefed-up radiators and a Boyesen Super Cooler help the bike stay cool in the heat, while a full Renthal drivetrain keeps things moving out back. A Pro Circuit Ti-6 Pro header and muffler finish off the motor mods.
You’ll find boot-eating titanium footpegs on his bike with grip tape to keep the legs planted. Roczen also fits his bike with half-waffle grips with donuts and a ribbed gripper seat cover from Guts Racing.
Roczen prefers pneumatic forks over the production’s spring forks.
Now The Fun Part
Contrary to what you might believe, Roczen’s bike isn’t a fire-breathing dragon. This isn’t what you’d expect from a “factory” race bike, right? Rather than trying to find tons more power, Roczen and his team said they actually “de-tuned” the engine to make it easier to ride. In fact, the 94-machine felt like it had less punch than our stock RM-Z. Sounds crazy, I know. Don’t get me wrong, Roczen’s bike still comes on strong in all the right places, but riding it gives you insight as to how Kenny can ride this bike at an all-out pace for 20 to 30 minutes. His bike feels responsive and noticeably light in the wrist. Engine braking is virtually non-existent and carrying roll speed into and through the corners was dramatically easier.
I found the transmission to be a bit tricky, as you had to click the bike into each gear with authority. It’s tuned this way on purpose so that he doesn’t accidentally bump the shift lever up or down a gear, or worse, into neutral, especially at the very worst time. Finding neutral is like a game of Where’s Waldo—first and second gears are pronounced, but that teeny gap in between is anything but.
Roczen’s bike makes strong and very useable power.
Kenny’s bike felt a bit longer and more stable than the standard RM-Z. Stability and comfort were the name of the game with Roczen’s Chicagoland setup, which was the most outdoorsy race on the SuperMotocross schedule, and I preferred this style over the pure Supercross option. The forks still felt firm but nowhere near as stiff as the stock units yet they were plush all the way through the stroke. The more you pushed the bike, the better the forks worked. It encourages you to ride it harder—the faster you go, the smoother it gets.
The rear shock felt glued to the ground, and I gelled with the bike right away despite being given a short window of time to ride the bike.
Roczen’s bike is proof that the RM-Z450 is still competitive with a little bit of tweaking.
Last Lap
I still praise the production Suzuki RM-Z450 for its comfortable ergos, razor-sharp handling, and manageable power. Unfortunately, an unbalanced chassis and manual kickstarting hold it back from its true potential. But in Ken Roczen’s case, he has the backing of a near-factory team to address every, well, most, of the RM-Z’s shortcomings. Kenny rode all the major brands during the off-season last year and chose the Suzuki. What does that tell you? That the RM-Z450 still has plenty of potential and riding Roczen’s bike certainly proves that. CN
We Ride Ken Roczen’s Race Bike + 2024 RM-Z450
RM-Z450
2024 Suzuki RM-Z450 RM Army Edition Specifications
| MSRP: |
$9199 |
| Engine Type |
4-stroke, single cylinder |
| Valvetrain: |
4-valve, DOHC |
| Cooling System: |
Liquid |
| Displacement |
449cc |
| Bore x Stroke |
96.0 x 62.1mm |
| Compression Ratio |
12.5:1 |
| Starting System |
Primary kickstarter with automatic decompressor |
| Fueling |
Fuel injection, 44mm throttle body |
| Lubrication |
Semi-dry sump |
| Clutch |
Wet multi-plate |
| Transmission |
5-speed constant mesh |
| Frame |
Aluminum twin-spar |
| Subframe |
Aluminum |
| Handlebar |
Renthal Fatbar |
| Front Suspension |
Showa Inverted telescopic, coil spring, oil damped, adjustable damping |
| Rear Suspension |
Showa BFRC-link type, coil spring, oil damped, adjustable |
| Front Wheel |
21 in. |
| Rear Wheel |
19 in. |
| Front Tire |
80/100-21, Bridgestone X30 |
| Rear Tire |
110/90-19, Bridgestone X30 |
| Front Brake |
Nissin, single 270mm |
| Wheelbase |
58.3 in. |
| Seat Height |
37.8 in. |
| Ground Clearance |
13 in. |
| Fuel Capacity |
1.7 gal. |
| Weight (curb) |
247 lbs. |
