Aprilia SXV 4.5

2007 Aprilia SXV First Ride

Aprilia includes supermoto as part of its off-road line. The SXV bikes are very similar to the RXV, but the differences are enough to warrant purchasing whichever bike based on your preferred style of riding.

SXV Supermoto

Admittedly, I don’t know much about the rapidly-progressing racing called supermoto. Though my interest in it has been high for awhile, especially with the increased popularity of the AMA series, I had never tried my throttle hand at it.

The faster journalists bitched up and down about the lack of a slipper clutch, but considering that those have only just started appearing on production sportbikes, that complaint seems a little premature. Not many manufacturers are even producing authentic supermoto bikes.

The sport has gained the most popularity in Europe, so it’s no coincidence that KTM, Husaberg, Sherco, Husqvarna, TM and now Aprilia. are the only real options for consumers looking to purchase a race-ready track weapon. American-made ATK is now offering a 450 Motard, but spotting one of those at the track will surely be a rarity. The majority of bikes on the American race scene are modified Japanese motocross bikes, but the Suzuki DR-Z400SM is the only one that is street legal in America and it’s not competitive on the racetrack.

While the speedy guys spent time between sessions discussing where the SXV falls short for high-level racing, I quietly pondered the value of these bikes for what they really are; a terrific platform for someone looking to enter the sport. Anyone who wants to try this kind of racing for amusement should skip dropping $8,399 (or $8,699 for the 5.5) and just buy a set of wheels that they can swap back and forth on their current dirt bike. But for those who supermoto on a regular basis and don’t want to spend a lot of time and money modifying their MXer, the SXVs are another viable option for taking it to the supermoto track.

Obvious differences in the requirements of enduro and supermoto racing have led to some significant changes. A stiffer 48mm fork, 17-inch wheels and oversized brakes are standard fare for Aprilia’s SM machines.

The SXV 4.5 and 5.5 are just as wicked looking as the enduro bikes, so you’ll look fast before ever laying rubber on the course. That was a comforting thing for a newbie like me, and fortunately there are more similarities than simple aesthetics. Nearly everything is just the same as the RVX bikes except for a few obvious areas of change.

As part of standard SM fare, the wheels have been changed to 17-inch rims to better suit the asphalt. Michelin knobbies have been ditched for a set of Dunlop Sportmax D208 meats, a 120/70-17 front and 180/55-17 rear. The motors are the same except for the ignition mapping which allows the revs to reach 12,500 rpm from the 450 and 12K from the 5.5, and an increased compression ratio of 13:1 (450) and 12.5:1 (550).

Transmission gearing has been lengthened to increase top speed in addition to a rear sprocket smaller by two teeth.

Traveling at a greater velocity means a necessity for more powerful braking. This comes by way of a 320mm front rotor with a radial-mount caliper. The rear unit is identical to the enduro model.

The supermoto version is more than 3 inches shorter at the seat and in terms of ground clearance, and combined with a beefier 48mm Marzocchi fork that better resists diving when you grab a handful of brake, it makes for a better platform for motard racing. The swingarm is also wider and can accept up to 6.5-inch wheels, an inch larger than stock, and the extended countershaft allows more chain clearance with a fat rear race tire installed.

The supermoto SXV models get basically the same treatment with their race kits as well. The major difference is in the exhaust. While the RXV system keeps the dual tailpipes, the supermoto kit eliminates the tail section of pipe completely, leaving a stubby, centrally exiting exhaust where the back of the airbox would normally be on a single-cylinder bike.

Power gains on the kitted bikes are a claimed 3.8 hp for the 450 and 4.5 hp on the 550.

The SXVs were very stable along the straight and settled through corners with precision. Holding your line is no problem on either the 450 or 550.

On the track I was relieved to find that supermoto isn’t as difficult as I had first imagined. Not that I was backing it in or anything, but I did reach my goal of scraping the pegs in a few corners. The SXV was stable and fearless while speeding down the back straight, and braking into corners was more predictable and responsive than in the dirt because of the consistent surface.

Riding the stock 550 was the most fun for me. The race-equipped 550 had a hell of a motor, but it took more effort to negotiate. Conversely, the 450 machines were easy as pie to flick around, but they lacked the fun factor when it came time to whack the throttle.

I could ride the stock 550 longer than any of the others and felt more rewarded with it each time I went out. It was also easier for my wobbly ass to settle into a line and hold it since the bike felt a bit heavier, though Aprilia still swears they’re the same 276 tank empty pounds. Its extra power and torquey delivery let me carry a taller gear that was just right for my lugging style.

Neither the SXV or RXV use a balance shaft, but the 180-degree firing pattern of the V-Twin motor produces less vibration than a single-cylinder big-bore. Vibes from the 450 were comparable to what you will get out of Singles with the same displacement, especially at high rpm.

Shifting the bikes was flaw in the machines we tested. Where the RXV was like butta’ rowing through the gears, the SXV didn’t want to upshift under a load, which is basically all the time on a supermoto track. The problems continued on the way back down the shift pattern. Approaching turns, a couple rapid taps on the shifter sends the rear end chattering towards the apex, and it gets worse the harder you push.

The addition of a slipper clutch would’ve alleviated this condition, but that didn’t stop Darryl Atkins, Aprilia’s U.S. supermoto racer, from laying down some fast laps with the back end hopping like a gold-spoked Buick in south-central L.A.

Factory rider Darryl Atkins was showing the newbies how to go fast in the dirt on slick tires. Actually, he was showing us how to go fast everywhere.

Perhaps the biggest flaw of the SXV has nothing to do with its performance, but the scope of its use. President Bush’s war critics should stop writing Dear Abby letters about a military withdrawal and start lobbying for the street-legalization of the SXV. If these babies were street-legal, the government would have no choice but to shift their defense budget towards increasing riot police here in the states.

This bike would turn every city in America into an urban playground. Hopping curbs, poppin’ wheelies, splitting lanes, terrorizing bike paths. Pedestrians, motorists, cyclists – no one would be safe.

Once people have experienced what it’s like to ride an SXV, traffic citations will shoot through the roof. Seriously, though, Aprilia does need to get on the bandwagon because the rest of the existing supermoto manufacturers have already realized the street potential of these machines.

In order to make as big of a wave possible in the American market, Aprilia already has bikes and service parts warehoused and ready to hit dealers this month, and several accessories are on the way. Such avant-garde design from the Italian company is refreshing, and anyone who can’t get excited about the bikes’ potential has a severely weak off-road pulse.

Watch for Aprilia to have a bigger presence in the American supermoto scene. SXV sales will reach even higher if a street-legal version arrives for 2008.

Aprilia has the guts to bring something different to the table, and it’s going to pay off big time. Born of a racing pedigree, the RXV and SXV are quickly building their competitive reputation across the pond, and with powerful, light, and well-mannered machines, that too will soon be expanding in the U.S. Not only does the Italian machine offer awesome performance capabilities, but owners will get the added bonus of possessing something different than the standard fare of Japanese and established European brands.

As a company, Aprilia’s three main goals for producing bikes are to achieve superiority in racing, design and innovation. After sampling these radical new creations, and considering that Aprilia has more than 50 riders competing in Italian supermoto and enduro racing alone, Aprilia’s Motorcycle Business Unit Director, Mariano Roman, pointed out something that was painfully clear to me by the end of the day.

This is a perfect blend of our intentions, he said.

And so it seems.

We hope you all think this bike is as cool as we do. Tell us why or why not in the forum .


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