MotorcycleDaily.com has received permission from our friends at Solo Moto, a Spanish motorcycle magazine, to provide the following riding impression of Suzuki’s new RM-Z450. The copyright of the English-language version of this riding impression belongs to Solo Moto, and cannot be reprinted, or republished, without written authorization.
Suzuki chose the motorcycle world championship circuit of Valkensvaard, in the Netherlands, to introduce what promises to be their most exciting release of the year, the RM-Z450 motocross machine. The bike uses a completely new chassis that has evolved from several previous designs after extensive testing with their official World MX Championship team. Since this is Suzuki’s first model in the 450 class, the only reference we have is the bike that made Kevin Strijbos a repeated winner. Although a world championship bike cannot be compared with a commercially available model, the RM-Z450 demonstrates Suzuki’s experience as a strong competitor. This is especially clear when looking at the chassis and the engine, which is probably one of the most powerful models in this category.
Everything in this bike is new, but what makes it clearly stand out from the crowd is the spectacular aluminum chassis that is at the heart of the design. In fact, the design is fairly different from what Suzuki has done with other RM bikes and the only common feature seems to be the front fender.
Suzuki has worked hard to come up with a winning formula. Even though they found inspiration in their successful two-stroke model, they have ventured further ahead. The motor has been designed with an emphasis on broad power delivery and compact size. This, in combination with the light chassis, make the RM-Z450 a strong but easy to control bike, in line with what is one of the distinguishing features of Suzuki’s less powerful models.
A Great Engine
Suzuki has worked hard at reducing the size and weight of the engine. In order to do so, they developed proprietary systems such as the SASS and the SAVS. The “Suzuki Advanced Sump System” (SASS) improves the oil flow by optimizing the performance and the space available. One distinguishing feature is the cavities of the screws on the cylinder head, which are used to drive oil up from the oil sump. On the other hand, the “Suzuki Active Vent System” (SAVS) improves the engine’s internal ventilation. The system has been designed with the aim of reducing piston pressure on the down stroke, thus improving the performance of the motor. Other features of this new engine are the titanium valves, the magnesium engine covers, and the automatic decompression valve. The transmission uses a four-speed gear box, a fairly common feature in this type of bike.
The carburetor is a Keihin FCR with a 40 mm (1.47 inch) diffuser and a TPS (throttle position sensor). Actually, the carburetor is where we see one of the bike’s downsides, since it is here and not on the handlebar where the hot start button is located. As other motorcycle manufacturers already know, this is not the most convenient location when trying to start a bike.
Finally, we should mention the exhaust system, which is designed with a titanium header and an aluminum muffler.
A Light Bike
At first sight, the RM-Z450 is a very narrow bike with a very flat seat. This design actually makes it easier to move around on the bike. The Suzuki chassis, tank, plastic body and radiator shrouds create a very clean and efficient design.
Designed with the comfort of the rider in mind, the bike includes titanium foot pegs and Renthal Fatbar handlebars. This is actually one of the unique features of the RM-Z450 chassis, since other manufacturers who use Renthal handlebars on their production bikes never feature the higher-end, stronger, Fatbar model.
One of the most original innovations in the plastic components of the bike is the longitudinal reinforcement in the rear fender, something rarely seen before.
The RM-Z450’s chassis has a twin-spar aluminum design built using a variety of techniques – the steering head is forged while the rear shock mounts are extruded. Overall, the different sections of the chassis seem to have large, strong cross-sections.
The forks and shock are by Showa. The forks feature tubes with a 47 mm diameter (1.85 inches) while the rear shock absorber has a 50 mm (1.96 inches) piston and a connecting rod with a diameter of 18 mm (0.70 inches).
Brakes are by Nissin, as is the case with many other Suzuki motorcycles. The front end brake line is made of Kevlar, which allows it to be smaller and more wear resistant. The front disk only needs four screws instead of the usual five or six.
The rear brake features Nissin´s new caliper, lighter and smaller than previous models.
According to Suzuki, Bridgestone designed the tires specifically for the RM-Z450.
Great Performance!
The first time we took the RM-Z450 onto the track, we were delighted by the awesome power of the engine. It not only sounds great, but offers a huge spread of power. There was no problem short shifting if we did not feel like reving out the gears.
The chassis took some getting used to. In fact, the faster we went the better it felt. It seemed to us that the bike had better control the more weight we put over the front end and the more aggressively we rode it.
The front end seemed a bit unstable, especially when taking corners with choppy ground, where the front tire didn’t want to bite. On the other hand, when exiting a corner, the bike handled pretty well and was stable enough to rocket down the next straight without letting off the gas.
We think that, with more time to experiment with suspension settings, including front and rear ride height, we could make the front end feel more planted.
In conclusion, a very powerful engine and a new aluminum chassis make the RM-Z450 a very competitive motorcycle, but at the same time this bike seems to work best with an aggressive, experienced rider.
If rider and motorcycle manage to work as a team, then the RM-Z450 is definitely a resounding success for Suzuki.
The RM-Z450 should be available at Suzuki dealers in the U.S. soon at an MSRP of $6,499. Take a look at Suzuki’s web site here for additional details and specifications.
