450s Four Ways

Want To Go Racing But Afraid You Can't Afford It? There's No Cheaper Way Than To Start With A Dirtbike.

By: Aaron Frank, Ari Henning, Brian Catterson, Marty Estes, Tim Carrithers, Photography by Kevin Wing, Ryan Keefe

Cheap racing. Of all the oxymorons, that's arguably the most moronic. Racing is the fastest way to turn money into noise. Always has been, always will be. And as you climb the rungs of competitiveness, it only gets more expensive. Want to beat the guy who blew his inheritance on engine work? Better cash in your 401K plan--and never mind that pesky penalty for early withdrawal.

Then again, racing motorcycles is about the most exciting thing a person can do. And there are some forms of racing that, if not exactly cheap, are certainly less expensive than others.

Consider the four motorcycles shown here. Never mind that two race on dirt, one on pavement and one on a bit of each--they all started out as 450cc motocrossers, which sell for around $7500. Change the wheels and tires, maybe make some engine, brake and suspension mods, and you're still looking at being ready to race for under 10 grand. And that's if you start with a new dirtbike--you could save thousands by using a used one.

Don't be put off by the state-of-the-art hardware shown here. These bikes are pure eye candy, chosen as much to entice you into reading this story as for their relevance. But do note that there is one from each of the Big Four Japanese manufacturers, so you can campaign whatever brand you'd like. And know that you don't have to modify your bike nearly as much as these to get started. Or at all: You can in fact dip your toe into the competitive waters on a factory-fresh motocrosser--and not just in motocross. There's nothing to stop you from racing a stock MX bike off-road, whether that's in an enduro, hare scrambles or desert race. Likewise, many dirt-track clubs have a Knobby class and supermoto sanctioning bodies typically have a Sportsman class for bikes with dirtbike-sized wheels. Spoon on a set of street tires and you could even roadrace in the Singles class.

Perhaps best of all, you could conceivably take part in all four of these racing disciplines with one bike and a few sets of wheels--harking back to the glory days of the AMA Grand National Championship, when racers rode the same bike in dirt-track and roadraces. That's good whether you're an old guy racing just for fun or a young gun aspiring to future greatness.

How do you get started? Just turn the page...

Motocrosser To Off-Road Racer In 46 Easy Steps
1 Suzuki RM-Z450 Off-Road Racer

Though converting a motocrosser into an off-road racer is a far subtler transformation than the other three bikes in this story, it still takes a significant effort--especially to compete at the national level. Motocross bikes are built without compromise and roll off showroom floors bare bones. Light weight is paramount, with explosive acceleration and stiff suspension capable of absorbing supercross-style triple jumps and whoop sections. Thus they're often too much bike for off-road racing, which throws a whole different set of obstacles at you, such as rocks, tree roots and river crossings.

This 2009 Suzuki RM-Z450 is campaigned in both the Grand National Cross Country (GNCC) series on the East Coast and the World Off-Road Championship Series (WORCS) in the West. In general, GNCCs feature tighter, more technical woods riding than WORCS races, which are faster and typically held on extended motocross tracks. If you're interesting in trying off-road racing, there are organizations in every part of the country running everything from timed enduros to hare scrambles to long-distance desert races.

Because Suzuki doesn't have a dedicated off-road bike in its lineup, the factory team has no choice but to start with a motocrosser. The other Japanese manufacturers all offer enduro models(Honda CRF450X, Yamaha WR450F, Kawasaki KLX450R), but because these are better suited for amateur trail riders than professional racers, prepping them for serious competition can take even more work. Their engines have to pass noise and emissions standards; their suspensions are tuned for mellow trail work; their wide-ratio transmissions are too widely spaced for tighter courses; and they're heavier and less powerful (as many as 10 horsepower down) than their motocross counterparts.

To build a motorcycle capable of winning at the highest levels of off-road racing, Suzuki carefully modifies the RM-Z to enhance performance yet retain reliability. Significant effort is spent trying to get the right kind of power to the ground. In addition to a Pro-X piston and mild headwork, the fuel-injection mapping and FMF exhaust are changed depending on conditions. A Hinson clutch helps the bike survive the oft-grueling races, which can run as long as 3 hours. An IMS gas tank holds 1 gallon more than stock, with a dry-break system for quick fill-ups. RG3 re-valves the suspension and provides a shock link with a revised leverage ratio to improve compliance and bump absorption. RG3 triple clamps with 1.5mm less offset increase trail for greater stability, while a GPR steering stabilizer keeps the Renthal handlebar pointed in the right direction. A plethora of aftermarket bits protect the RM-Z's engine and chassis from brushes with Mother Earth.

An all-too-short test ride on GNCC racer Charlie Mullins' factory RM-Z showed this to be one of the most confidence-inspiring dirtbikes we've ridden. The mildly massaged motor is plenty fast, with power everywhere you need it. But it's the suspension action and cornering that really blew us away. Where stock 450cc MXers have a "see-saw-like" feel over jumps and bumps, the factory RM-Z is much more stable and controlled, marrying plush with firm. As is often the case, a lot of little stuff really adds up. The factory team's testing and attention to detail created a bike that's versatile yet supremely capable.

Not to mention expensive, and $14,000 is a lot of dough to go racing. But depending on your weight and skill level, you'll likely achieve appreciable results by leaving the motor stock. Adding weight to the flywheel can help tame power delivery for tighter/more technical conditions, and adding a quieter slip-on silencer with a spark arrestor is absolutely necessary. Having the suspension re-sprung/re-valved is money well spent, and if you want to keep engine fluids where they belong and the brake rotors straight, you'll need guards. Granted, without the fancy factory bits your bike won't perform like Mullins', but unless you ride like him, it won't matter one bit.

Suzuki RM-Z450 Off-Road Racer
What You Need

Re-done suspension, quieter silencer/spark arrestor, heavier flywheel, larger gas tank, engine/chassis guards

What A Pro Needs
Motor work, full exhaust, recalibrated EFI, heavy-duty clutch, personalized bars/clamps/controls/seat, gearing, tires with flat-proof inserts

How much?
$10,000 to get dirty
$14,000+ to run with Mullins & Co.

By Aaron Frank, Ari Henning, Brian Catterson, Marty Estes, Tim Carrithers
Enjoyed this Post? Subscribe to our RSS Feed, or use your favorite social media to recommend us to friends and colleagues!

*Please enter your username

*Please enter your password

*Please enter your comments
Not Registered?Signup Here
(1024 character limit)
  • Motorcyclist Online