2015 SUZUKI RM-Z450

Suzuki’s 2015 RM-Z450 has a host of long overdue changes. While the motor has always been strong and smooth, the new bike benefits from a significantly improved chassis. Basically, the frame has been redesigned to increase flex and give the rider better feel. This takes away the rigid feel and harshness of the previous bike. Second, Suzuki has tossed away the spring in the SFF fork (Separate Function Fork) and joined the air-fork game with the Showa SFF-AIR fork.

Similar to the one found on Kawasaki’s KX450F, the new Showa SFF-AIR fork gives the 2015 RM-Z450 a unique feel. Handling is improved over the previous bike, although there are some drawbacks. Frankly, initial setup is a chore. First, you have to find a balance between the inner and outer air chambers, then you have to dial in the compression and rebound damping.

Once set up, the new open-class Suzuki motocrosser handles fantastic, but the feel is totally different than with a traditional spring fork. The harshness of the previous bike’s design has been reduced, and in some situations, it can be dialed out completely. I preferred a stiffer setting, which still meant I could feel a bit harshness through my hands.

Engine upgrades, which include a longer kick-start lever, a redesigned de-compressor, and a revised exhaust camshaft, plus a new kick-gear ratio and starter idle gear, make the Suzook easier to start. These mods also allowed for removal of the hot-start lever. Cooling has also been improved, thanks to a more efficient water pump (with a redesigned cover and Y-type hose connector) that allows water to flow more between radiators. The gearbox also has been improved to make shifting less clunky than with the previous RM-Z450.

Last, the 2015 Suzuki RM-Z450 has Holeshot Assist Control. In A-Mode, the ignition timing is altered to prevent wheel slip. But after 1.2 seconds (or when you reach third gear), the system shuts off and the engine returns to normal ignition timing. An indicator light flashes slowly to tell the rider he’s in A-Mode. B-Mode advances ignition timing for more power off the line, and it returns to normal only if the throttle has been open for 4.5 seconds, you’ve reached fourth gear, or the throttle has been closed. B-Mode is best used to get out of the gate in a hurry, but the conditions must be tacky. A smooth track helps with traction, but skill and reaction time are still the determining factors when it comes to getting holeshots.

We’re glad to see American Suzuki bring a competitive 450 to the market, and we feel this updated bike will help lead the brand out of some recent. And once come to grips with the tuning of its new fork, the new 2015 RM-Z450 will lead some races as well.