2013 Suzuki RM-Z450

Name: 2013 Suzuki RM-Z450
Brand: Suzuki

Long regarded as the leader of the 450cc motocross pack, the 2013 Suzuki RM-Z450 has come in for a bit of refinement with the competition hot at its heels

Suzuki’s RM-Z450, on its release in 2005, was a little bit behind the rest of the competition. You see, Suzuki had waited a couple of years after the likes of Yamaha released their new generation of 450 motocrossers.

With the new age of 450cc four-stroke bikes seeing off the last of the two-stroke 250s, most manufacturers concerted their development efforts solely on the four-strokes. This made it no easy task to produce a standout motocross bike for the major Japanese manufacturers as they went head-to-head – along with KTM – in the MX1 category.

But from the RM-Zs first release it proved not to be lacking and hit the track vying for the rights to be the class leader, winning many domestic and international titles over the past seven years.

In the face of some seriously hot new competition of late like Kawasaki’s ground-breaking KX450, Yamaha’s radical YZ450F and Honda’s all-new CR45-F, the question has been just what will Suzuki do next with its fifth generation of the RM-Z 450.

Over the last few years we have seen a constant and calculated evolution of the RM-Z and, as far as changes go for the 2013 model, there are again plenty of them. The main points of difference are in the engine, forks, exhaust and frame. Elsewhere, there are a host of updates spread across the bike, each as small and significant as the rest.

The powerhouse 449cc four-stroke engine has a lighter crank/conrod/piston unit. The drop in reciprocating weight makes for a faster spinning, more receptive throttle response. That’s combined with improved combustion efficiency in the top end with a new intake camshaft design, faster processing ECU, revised intake tract and new coil. Elsewhere, another change contributing to the engine improvement is a better oil filtration system for improved oil quality and life.

They may only seem like a few small changes, but together they make for a good deal of improvement on what was, arguably, the leading 450 motocross bike in terms of performance and reliability.

Throttle response from idle is everything Suzuki has set out to make it. The RM-Z really hauls off the line and has a beautifully linear delivery right the way through its useable range. It pulls hard low in the rev range and is really tractable. It made me a better rider than I am in the deep filth of a wet, muddy track. In riding conditions that demand for a high level of control from front and rear wheels, the level of traction and control shone out as the strong point of the RM-Z package.

The fuel-injection system derived from the GSX-R sports bikes is faultless. The added tuneability – through removable couplers allowing fueling to be changed tool-free between lean, standard and rich – is something most riders wont seek to play with, but is something club and amateur level riders will benefit from. There is also a small change in the gearbox with a slightly reshaped shift-cam for better changes. The five-speed box is positive in its changes and with a good spread through the range.

A much quieter exhaust, thanks to a redesigned muffler internals and a slightly longer pipe, has not only made the RM-Z quiter, but Suzuki says it has also contributed to the increase of power and torque from the bottom end to the mid-range. No longer is a quieter bike a less powerful bike!

Just as well as the power delivery makes for a user-friendly ride, does the chassis. The biggest change is the adoption of Showa’s Single Function Fork (SFF), first released a couple of years ago on the Kawasaki KX450F.

The Showa SFF runs the spring in the right leg and rebound damping in the left tube. There are two reasons why this system is said to be better: by separating damper and spring there is less friction in the fork thus improving actuation, and there is a weight saving by running the two components in each fork leg.

The steering is pin-point accurate on the RM-Z, and is just as good as the braking package. The feel and power of the front brake is excellent, and there is plenty of rear brake – something that can be hit and miss between motocrossers.

The size of the RM-Z is deceiving at first. It’s packaged tightly around the frame spars and top of the engine so you can get your legs hard around the edges. The ride triangle is set very neutral out from the bars and up on the pegs. You don’t feel like you are standing down in the bike or up over the bars. At my six-foot it is just the way I like it. To tailor things slightly I’d prefer a slightly wider and taller bar to get my shoulders up a bit higher.

When it comes down to choosing a 450 MX bike, you might have heard the ‘pick a colour, they are all the same’ spiel all too often. It’d be nice if it was true as it makes choosing a lot easier, but all the bikes on the market are distinctly different in what they have on offer to a rider.

What the RM-Z has seems to be a perfect balance: a rider-friendly nature, but it is in no way the mild one of the class. It has handling and engine performance that is hard to beat. The RM-Z has been updated to keep it at the head of the field – something that is proven to work as Davi Millsaps leads the 2013 AMA SX title after a dominant season to date.

The $11,790 bike oozes performance and rideability – two things that’ll ensure that the RM-Z continues to be a winner in sales and on the track.