The cream of the crop. The crème de la crème . The premier class.
But some say the 450cc dirt bike ruined Motocross and Supercross. Wherever you lie, 450s remain the elite pro racing standard when it comes to off-road and MX track riding, thus those who must, get one, whether or not they can handle the power, torque and speed.
Speaking of speed. How fast does a 450cc dirt bike go?
We'll just say fast. Super fast. Like all engine sizes, it really depends but a 450 contains so much hidden power you can get these high-end rides moving fast at the gatedrop, the finish line and everywhere in between
What Is a 450cc Dirt Bike?
Every would-be dirt bike racer aspires to the 450 class. It used to be the 250 class, but many, many years ago the 2-strokes got canned in favor of all 4-stroke dirt bikes so the once 250 premier class turned into the "lites" class giving way to the powerful 450 premier class. Just about every sanctioned pro dirt bike racing event - Motocross, Supercross, GNCC, MXGP (even Arenacross) - drops a 450 class gate. Some industry folk say the 450 bikes pose way too much power for the smaller tracks resulting in a lot of unnecessary injuries on Supercross tracks. Indeed, a beginner should not start on a 450 bike and many weekend warriors find them simply too powerful for their liking.
The 450cc equals a unit of volume to describe the size of the cylinder bore. The larger the bore the more fuel and air mixture allowed which generates power. Torque and acceleration define these bikes but the overall speed still cannot compare to that of the common street bike. In other words, fast but not that fast.
Factors Influencing the Speed Capabilities of a 450
A stock 450 dirt bike roars off the showroom floor. It requires finesse, agility and determination to master. For someone graduating from the 250 class, a stock 450 probably offers enough authority to challenge their skill levels. Equip one with a load of aftermarket parts it no longer resembles the now mediocre offering you rode off the showroom floor.
A new exhaust, clutch, handlebars, wheels and intake system join forces to lighten the load and boost power to turn this machine into a rocket. Add race fuel... well, never mind, most riders will never tame this wild beast to enjoy the burst you get from special gas. Modern 450s come with electronic tuning allowing you to make further adjustments, called mapping, to the engine's fuel injection and ignition systems that optimize performance and increase power, among other things. Changing the sprockets (more teeth in the front, less in the rear) also contributes to overall top speed.
A rider's weight plays a role as does their riding skills. If you ever wonder why the pros seem so persnickety about fine tuning their dirt bikes, understand that at the highest level a few pounds makes a difference.
But so does terrain. When discussing the top speed of a 450 dirt bike the biggest obstacle lies in the soil or lack thereof. The preferred loam of a Motocross track that helps riders stay on four wheels and enjoy everything a Motocross track offers, rightly slows you down, unlike a hard pack desert trail which lets you rail, at least on a straightway. However, to truly achieve the top speed of a 450, you need pavement.
You can get going pretty fast riding down hill on a 450cc dirt bike
450cc Dirt Bike Top Speed
Now that you know what affects, positively and negatively, the top speed of a 450 dirt bike expect, on average, to reach between 80 and 90 mph under ideal dirt riding conditions for an expert rider meaning a level dirt path on dry hardpacked soil. Rider experience and skill also comes into play as weekend warriors used to moderate speeds probably cannot handle, nor have the upgrade in equipment to effectively control their bike at these speeds.
On pavement, speeds easily exceed 100 mph especially with aftermarket performance parts installed.
Remember, even with aftermarket parts a dirt bike's overall performance lies in the amount of torque and power to the ground which helps with traction and control. Top speed indeed plays a role in who crosses the checkers first but those who learn to go slower ultimately go faster, even faster than someone who breaks the dirt bike sound barrier.
If you have the need for speed, consider a date with Tom Cruise or look into any number of motorcycles often referred to as crotch rockets.
