Launch: Suzuki RMX450Z ADR version

It's like the first day of school again for Suzuki Australia. Five years after it first launched the RMX450Z enduro bike, based on the RM-Z450 motocrosser, the company has finally released a full ADR version of the bike, which puts it onto an equal footing with opposition like the Kawasaki KLX450R, Yamaha WR450F and Honda CRF450X. And it's generated some genuine excitement, rather than limiting the fanfare to states such as Victoria and Tasmania which offer a recreational registration scheme.

It's not a cheap exercise – the conversion to ADR-spec is completed by a Melbourne-based company – but Suzuki knew that the RMX450Z couldn't ever hope to achieve parity in the enduro stakes without it. And the company is confident that its 'full-flavour' RMX package will deliver them strong sales in years to come, with marketing boss Lewis Croft forecasting annual sales of "over 500, but under 1000" units for the $12,490 machine – just $500 more than the non-ADR version.

That is RMX250-esque type stuff for Suzuki. The RMX250 was the racy, road-legal two-stroke enduro bike that was sold in the late ’90s and early nougties, and was highly popular for its ability to weave its way through trees with a minimum of fuss. Suzuki sold about 2000 of them from 1998-2001.
Other than the addition of the ADR bits and bobs – chain guards, blinkers, etc – the RMX450Z hasn't changed from the original bike that was first launched in 2010.

Compared to the RM-Z450 motocross bike, the RMX scores a hinged airbox cover for easier filter changes, a plastic bashplate, sidestand, electric start and battery, and an 18-inch rear wheel. There's also a neat multi-function digital speedo, complete with a fuel level warning light. You won't find that on the motocross model.

Internally, the RMX and RM-Z differ in their cam timings, fuel intake, gear ratios and suspension settings. The aim for the RMX was to shift power to the bottom-end and mid-range for improved performance at lower revs.

In standard guise the RMX450Z is choked up with various restrictors, but to gain the full race-bred experience the bikes supplied for the Australian launch were derestricted and ready for competition.

For the 'relaunch' of the new-age RMX450Z, Suzuki enlisted the services of Mt Buller Motorcycle Adventures to take us on some of the finest bush trails around the base of – you guessed it -- Mt Buller. It's trail riding heaven with a variety of trails, river crossings, sinuous single track, steep climbs and sketchy descents – one of them my undoing… -- so how did the RMX handle them?

For someone who has minimal experience punting competition-bred 450cc enduro bikes through the bush, the RMZ was certainly a challenge for me, especially in the tighter terrain which we hit straight off the bat in the morning. Massively enjoying but I was tiring at a rapid rate of knots trying to keep the RMX tracking at a respectable pace. The bike also felt a bit top heavy as I couldn't get the front to bite as much as I'd like. And I stalled the bike a few times – the luxury of electric start cannot be underestimated!

However, once I backed off the compression a few clicks it became way less heavy-handed: the softer settings were far more in sync with my speed and ability, rather than the harder dosage I started out with. As a result, my confidence grew and the anxiety lessened, and my enjoyment levels went through the roof.

There are 23 clicks of rebound and compression adjustment on the RMX forks. It's competition-orientated alright with such close links to the RM-Z450, but bread-and-butter trailriders should not fall into the trap of believing the bike is too much for them: even some minor tinkering can make a huge difference to feel and balance.

I love the strapping engine with its aggressive throttle response and oodles of fuel-injected fed power – brilliant on open fire trails. Get the 449cc liquid-cooled single humming and only the steeliest terrain will make you second guess. As the RMX sits at the base of a hill, all ready for combat with its raspy exhaust note (in derstricted trim…) , it really puts a steep hill on notice rather than the other way around.

The mid-range is a delight and, with the internal gear ratios in the five-speed gearbox tweaked for enduro use, including a much shorter first gear and taller top gear, you're never far away from the sweet spot. Only the third gear ratios for the RM-Z450 and RMX450Z are remotely aligned, otherwise all the other gears are all totally different.

After the challenging morning in the tighter terrain, the chance to open the throttle on the RMX was most welcome. With the softer front end I was already more confident, and I also felt I was riding harder as well – with the RMX responing in kind. Despite its high level of tuneability for different skill levels, it's obvious the RMX works best when ridden hard – and some of the fast men on the launch, including hardened enduro riders, were proving that in spades.

Things were going swimmingly, but about two minutes before lunch the enjoyment evaporated for a couple of minutes when I lost the front end going down a rut-laden descent, crashed, and then cannoned into a log on the side of the track. It hurt. My Bikesales colleague Steve Martin was on the scene in seconds and picked up the (undamaged) RMX while I regained my senses. Nothing broken, and only some bruising to show for my effort.

The short blast after lunch factored in a bit of everything and, even though I was sore, I felt demonstrably faster on single track in particular. The RMX felt balanced and settled, my corner speed was higher, and the RMX was hardly breaking stride compared to my stuttering early morning 'campaign'. And animation is what the RMX does best.

Despite enjoying the pointing and shooting, I still deferred to the 'soft' way back to base at the Sawmill Settlement, with the hard option amounting to an extremely rut-laden 800-metre descent. I have no doubt that the Pirelli tyres fitted to the RMX on the launch, a MX32 front and XC mid soft rear, would have helped me out, but another crash would have sullied what had been an excellent day.

Without a motorcycle in my garage at present, I'd be more than happy to fill that space with an ADR-spec RMX450Z, as I only live five minutes from some awesome trails north of Melbourne.

This is a bike which loves to take fast and furious route, but with a level of refinement that doesn't exclude the trailriding set. And with ADR compliance, there's a whole new market beckoning for Suzuki's enduro flagship.

As well as the WR450F ($12,999), CRF450X ($11,590) and KLX450R ($10,999), other opposition for the RMX450Z includes the KTM 450EXC ($13,795) and Husqvarna FE450 ($14,095).

RMX450Z IN BIKE SHOWROOM

SECOND OPINION
I thought Suzuki was pretty brave launching the road-registerable RMX450Z at Mt Buller. It's steep, loose and aggressive single trails are the sort of thing that normally would suit a 250, while wearing the user of a big bike down. We didn’t start off with a gentle warm-up either, as it was straight in to the tight stuff. I have to admit that I was surprised at just how agile the Suzuki was but I knew I had a lot of power on tap to deal with. The power is all torque and easy to manage, but I found the suspension setup for the pro rider and a little stiff. At lunch I backed off the compression damping front and rear which suddenly transformed the bike. It became very plush and gave me a feeling of confidence just like a 250 would. The power delivery, the handling and the forgivingness of the chassis really came into their own on the way back to camp. The best part for me that rounded out a top day was the fire trails where the big Suzuki's neutral balance meant speedway slides were spectacular and easy. – Steve Martin

SPECS: SUZUKI RMX450Z
Engine: Liquid-cooled, DOHC, single-cylinder, four-valve four-stroke
Displacement: 449cc
Bore x stroke: 96 x 62.1mm
Fuel supply: Keihin fuel injection
Transmission: Five-speed
Front suspension: 47mm Showa
Rear suspension: Showa shock
Fuel capacity: 6.2 litres
Claimed wet weight: 123.5kg
Seat height: 950mm
Warranty: Six months
Retail price: $12,490