First Test: 2005 Suzuki RM-Z450

There's a saying: Better late than never. And we say: Better watch out for the late ones because they get to see what they're up against. Honda did it to Yamaha in the four-stroke MX wars, and now Suzuki is looking to do it to the rest of the field, Honda included. But first we'll look at why the bike was late.

Suzuki was making a bold statement about a year ago when they announced they were entering the most hotly contested class in the dirt bike market. The RM-Z was looking to upset the CRF450R, which has a stranglehold on the class, if not the entire MX market. Think about the time it takes to develop a bike and you'll realize Suzuki needed some serious hustle to get the bike done in time to be a 2005 model. Prototype bikes quickly appeared at test tracks and international races. And as fast as they appeared, they changed, showing the fast pace of testing at Suzuki. As early as late last summer, a picture appeared of the supposed "production" version of the RM-Z450. Yet we'd still see the Suzuki test guys out riding a bike that was slightly different. About this time the 2005 Honda CRF450R hit the magazine test circuit, and word spread like wildfire about how improved this machine was. Hence our Honda test's title "Moving Target" (Nov '04). Still in a flurry of testing, the Suzuki engineers were seen even more frequently, causing some to speculate that they were changing the bike even more. Press introductions for the bike were announced and then pushed back a "few" weeks so many times, we went ahead with our 2005 450cc four-stroke comparison fearing that the bike was going to get pushed back until 2006.

About this time the press release hit the newsroom proclaiming "RM-Zs rolling off the production line!" Damage control? We'd heard from Suzuki dealers that guys with deposits were taking back their money and heading over to Honda. With the press introduction still not set, it leaving us wondering: "Do they want the RM-Z in dealers before any press hits the streets? If so, is it because the Honda is a better bike?" All the while Suzuki Racing is continuing to race a "works" RM-Z even though the bike could qualify for the production rule, like the still-unreleased KTM SX 250 four-stroke did. If there was ever a bike with a rain cloud over its head, it was the RM-Z450—so much of a rain cloud that the day we finally received the bike, it was the first sunny day in So Cal in weeks and nearly every track available was underwater!

As you've surely read in our first impression, we were impressed with the bike right off the start. But sometimes it takes a little while to really shake things down, and that's what we did. The RM-Z has been at the track, nearly non-stop, since the introduction and we're still riding it, now back-to-back with the CRF for a full-blow comparison.

Right off the bat, the Suzuki takes a healthy boot of the kick-starter to get going. It feels like there is a high-ratio to get the motor spinning, and it is a high reach to get the full stroke. But with a strong swing the bike fires right up. And she's a throaty beast as well, with a pronounced bang when the throttle is cracked. You immediately get the feeling that the Suzuki is a much more traditional four-stroke than most of the other big-bores out there. It makes big-stroke power and torque from a very low rpm, and pulls smoothly. You feel the thumps as opposed to a revvey blur, and it gives you confidence about dipping into very low revs when coming out of turns. Power builds so smoothly that there isn't really a hit or surge through the entire power delivery. It takes a little while to go through the spread, and because of that, the Z has that great four-stroke hook-up. The bike gets traction on even the slickest surfaces.

A power spread like the RM-Z is good for working through a four-speed gearbox. With a first gear that is low enough for the tightest of turns, there is little need to be shifting much. Starts and most corners are second's chore. Third handles a lot of corners and most straights, and fourth is for when the track opens up. We ran the bike on a high-speed GP course, and found that fourth gear's legs were plenty long enough for the fastest stuff you'd ever encounter on an MX track—even with stock gearing. This great power will have you pulling a gear high on a lot of turns, and here is where its superb clutch action comes into play.

The control and feel of the clutch are excellent, and that makes slipping out of a turn a simple task, and a common one too. We found ourselves doing this a lot, and the clutch seemed up to the abuse without so much as a squeak. Stalling wasn't an issue unless the idle was set really low, and the bike would usually fire right up. But in a crash, where you might have to go to the hot-start button, you'll lose time since it is still on the carb. A bar-mounted hot-start lever would be our first aftermarket purchase.

The interesting thing about the RM-Z is that it has exactly the four-stroke power that we thought Suzuki wouldn't make. We were expecting a more rev-oriented power spread and an aggressive delivery, things that the RM-Z is not. It may not feel like it makes a ton of power, but sometimes a spread like this can be very deceiving. It isn't slow! Mellow to a point and exciting for sure, but also one of the most rideable four-strokes on the track.

Moving on to the chassis and handling, the RM-Z continues to impress. We guessed wrong and thought the bike would keep with the Suzuki trend, setting standards for a light-feeling bike, perhaps on the twitchy side. The Suzuki is light at 233 pounds on our scale (without gas), but it isn't what we'd call feathery on the track. It has a planted feel and combined with the thumps of power, it has some mass to it. But the RM-Z's weight feels consistent and doesn't get heavier as the rpms go up. The crank's placement seems to have struck a good balance.

Yet another surprising trait of the RM-Z is stability. When we were testing on the wet, rutted track of Racetown 395, the bike didn't have the opportunity to shake its head. On our GP course it had every opportunity on the fast, choppy straights, but the front end stayed calm. This finding was backed up at I-5 MX. Turning was even more surprising; it was even better than the stability. We've always liked the RM line's effortless turning, but with the four-stroke motor holding things down, it is even better. This could be one of the best-turning bikes ever. It is not as light as a two-stroke RM, but then there aren't many bikes that are this stable and controlled in corners, either. The front end is very planted, and steering control is great. It is also seemingly unaffected by ruts. The larger 90/100-21 front Bridgestone helps things out here by gripping in places thinner tires don't. A small sacrifice in weight feel is worth the added grip. And both front and rear tires performed exceptionally and showed astonishing durability.

Suspension set-up is extremely important with the RM-Z; the ride height is especially vital. The handling we just raved about can go right out the window if you're just a few clicks off on compression or let the sag ride too low (104mm is recommended). Another crucial setting is on the fork height. The line on the top of the tube should be 3mm above the top clamp, lowering the bike in the front. Suzuki found in testing that this was the ideal setting, and most of our test riders agreed.

Overall the Showa suspenders do a great job of providing a plush, controlled ride. On soft terrain they are magical. They're plenty stiff so bottoming isn't a big concern. The initial stroke is compliant without being very harsh. On harder terrain, the initial stroke gives a bit more feel to the rider and you notice the bottoming a little more when the ground doesn't give. The shock has a tendency to use up the stroke quickly. A little extra high-speed compression helped. Any time the bike started to dance around or feel stiff, we found it was riding too low in the rear. The best cure was to check the sag or stiffen the compression to hold the bike up higher in the stroke. Opening up the rebound damping was also an option, but it wasn't as effective. Our ideal settings for riders in the 180 pound range was between 4 to 8 clicks out on shock compression, 2 to 2 1/8; on high-speed and always close to 9 out on rebound. The fork was less critical and we ran 7 on compression and 9 on rebound.

If you can't tell already, we really like the bike! So with such a good bike, what was the real reason for the delay? Evidently it was production issues and making sure the durability of the final pieces was up to standard. Most of the parts were done many months ago, waiting on the last bits that weren't ready. And with a crowded production line pumping out a lot of other very-important bikes—like the GSXRs—it is hard to slip any dirt bike in, even one as important to Suzuki as the RM-Z. Then, making sure there will be spare parts available shortly after the bike is released to dealers. Sure, there was some damage control going on due to its late arrival, but it wasn't to the level our speculation led us to believe. The RM-Z is good enough that we're out right now racing it against the CRF to see where it stacks up. An impossible challenge? Some might say as impossible as building the best motocross bike in a year's time.

Opinions

At first I was skeptical about riding the RM-Z, knowing that it was a first year aluminum frame for a Suzuki dirt bike. It brought back memories of the '97 CR250, which I thought was the most ill-handling bike ever. Honda is now on its 4th generation frame, and finally, after a lot of trial and error, they have worked things out with aluminum. Knowing how long that took, I was extremely surprised at how well the RM-Z handled its first time around. After three days of fine-tuning the suspension—finally with a little help from Karel—the RM-Z was amazing. The suspension settings were particularly sensitive; one click up or down made a big difference. Another thing that really stuck out was the front brake. It seemed to stop the bike better because of the larger front tire. I really have nothing bad to say about the RM-Z. My only question is: How's the durability?
Tod Sciacqua 5'8"/ 170lb./ Vet Pro

As you can read in the test, I was the biggest skeptic about this bike. Especially watching from the outside and comparing what was happening to what I'd seem before. But boy was I wrong, and now I feel like eating crow, but I like it! Cause I really like this bike and for a lot of the reasons I thought I hate the RM-Z. I've found most RMs to be aggressive bikes, demanding a ton of rider attention, never allowing me to relax while riding. This is exactly what the RM-Z 450 isn't. Starting with the engine and carrying through to the chassis, it is one of the easiest bikes to ride fast on. I can ride it substantially longer than other bikes without getting tired. I don't seem to have to shift much. Very little clutching. Doesn't matter where you want to turn, the bike does it. Traction on the slipperiest places makes jumping safer for me. The only time I didn't like it was when the suspension was off, but you quickly know something is wrong and then you fix it.
Jimmy Lewis 5'10"/190lb./Vet Pro