Dancing Suzuki
Published: 30th November 2007
Author: Johnno White
Feast your eyes on the all-new Suzuki RM-Z450
SUZUKI is now in its fourth year of building 450 strokers, the first year was 2005 and when it finally came out... because it was released late it was pretty trick but didn’t take off as well as Suzuki would have liked. In 2006 it was modified slightly and became more popular round the paddock but still not as popular as some of its competitors, but then in 2007 it seemed that Suzuki was now one of the front runners in the 450 trend but now for 2008 I think you will see even more than ever because the new RM-Z450 is the dog’s danglers and the closest your going to get to a factory bike without actually buying a factory bike.
The new model has undergone some serious surgery, starting with a completely new frame and swingarm, similar to that of its little brother the RMZ-250F, to give the rider a more comfortable ride and help make the bike turn faster and handle much better generally.
Cosmetically, it has received a complete facelift too and gets a totally new look with different fender and number board, new shaped rad scoops, new seat and air box, and new rear fender.
One of the trickest looking changes is the new petrol tank which, for the first time ever on a production bike, is constructed out of aluminium instead of plastic. Even more surprisingly, it is the same weight as the plastic one of last year.
It is not purely a cosmetic thing though, and its primary function is to provide a better seal for the integrated fuel pump which feeds the most exciting change to the RM-Z450, and the one everyone is talking about, the electronic fuel injection system. Yes that’s right, EFI.
It is well-known fact that the 2008 RM-Z 450 is the first production Japanese motocross bike to come with fuel injection, so gone are the days of re-jetting your carb if you want to alter the fuelling on this baby.
Using technology borrowed directly from its hugely successful GSXR superbikes and road-race teams, and the LTZ450 Quad, the EFI unit is a battery-less system built by famed carb manufacturer Keihin and says Suzuki provided the benefits of instantaneous throttle response at all times, improved pick-up and power delivery, especially in the low to mid-range, and of course a regular, linear power delivery in all weather and atmospheric conditions.
The exhaust system has been changed too the new front or header pipe is very similar to the power bomb header that comes from FMF, this was done to offer more low down grunt, the foot rests have come with a new design with a mud protector added to the root of the foot rest mounting section to stop them clogging up in really bad muddy conditions, and to top all this off it comes with a set of wavy discs.
So enough of the technical, what was it like on the track?
Well we had to go to the impressive Valkenswaard GP circuit over in Holland to find out, and it is safe to say that the new RM-Z450 didn’t disappoint.
It was easy to ride straight off the bat and in particular I found the new chassis layout much more comfortable and better performing on the track than last year’s model.
The engine is more useable in just about every situation too thanks to the combination of the EFI and other mods, and especially the move to a five-speed gearbox instead of four-speed. Although I personally never felt the four-speeder had issues, a lot of riders just didn’t like it, and to be honest to move to five-speed was definitely the way to go and it has made the delivery of the power more useable becauseeach gear is just that bit longer.
The most noticeable and impressive thing on the engine side of things was the fuel injection though.
Because of the heavy sand and need to be quite hard on the throttle at first I struggled to tell any difference over the carburated models, but as I got more comfortable with the bike and its characteristics the benefits really became apparent.
Where it is really good is dropping down on the landing from a jump, say a drop-off or step down. Where with a carb fed engine you get the feeling the bike would bog a bit on landing and there is just that split second lag between you opening the throttle and engine reacting, with the fuel injection there is none of this. You can land from any height, carrying momentum or landing like a sack of spuds, hit the throttle and the power is instant, clean and with no flat spots at all. It’s a real confidence booster.
What was also really impressive was the injection systems ability to get the bike to run cleanly and still pull well out of corners in the taller gears.
Fifth was out of the question obviously but the bike would easily pull third and fourth gears out of slower corners with absolutely no problem at all and the throttle response was instantaneous and without any coughing and struggling that card-fed bikes suffer from. This allows you to not have to be so precise with your gear selection, and also lets you get away and maintain some forward motion if you do get it a bit wrong coming into a corner. The bike is also very hard to stall which is another plus point, while starting the bike, whether hot or cold, was an absolute doddle and this is definitely down to the fuel injection. Twenty minutes into a race when you’ve bitten the dust, you’re going to be thanking Suzuki for EFI without a doubt.
Handling wise, I found the new RM-Z 450 a pretty good all-rounder as always, but was noticeable more comfortable and forgiving out on the track, which I was really impressed with.
I usually find the front-end on most 450s sprung a bit hard and too fast on the rebound and the RM-Z450 is no different. I felt like it wanted to ride out of the loose stuff a bit too easily, but this is nothing a revalve or softer springs couldn’t change. The rear end, though, was sprung perfectly and tracked superbly through the corners, no doubt helped by the new permiter frame that definitely provides a sharper handling, more forgiving ride and better feedback to the rider. In sweeping stuff in particular it felt much improved.
The new ergonomics were a noticeable improvement too and made for a bike that felt just ever so slightly more compact, less bulky and easier to move around on, and when teamed with the new frame it created a very light, nimble feeling bike for a big 450.
The brakes worked good as you would expect nowadays and never suffered from fade all day, although I don’t think this is anything to do with the new wavy discs in particular, the brakes were just as strong previously, I think they are more for show despite Suzuki’s insistence that they stop fade and keep them cooler.
All-in-all, I was very impressed with the RM-Z 450 and the progression it has made over previous years, with the fuel injection and benefits that brings the particular stand-out. In fact, the only down side I could find to this bike was the lack of actual track time I got on it, just two 25-minute sessions. It would be nice to really put it through its paces in this country and on a track surface that really provides the opportunity to see how EFI really shapes up.
Anyway, as far as I’m concerned the new 2008 RM-Z 450 is a piece of motocross history in the making and I’m sure you will see a lot of these about on the track next season.
See T+MX News, Friday, November 30, 2007 for more pictures.