How Fast Can a Motocross Bike Go? Dirt Bike Average Speeds by CC

Motocross bikes are fast and sometimes we don’t get to see how fast they can really go. When you’re standing side-track at an event, or wanting to ride a bike yourself, you might find that motocross bikes never race as fast at the bike will allow because most obstacles can not be taken at full speed. 

Motocross bikes can go at speeds of up to 100 miles an hour and more. Although they can match the speed of an on-road vehicle, motocross bikes are rarely driven at their top speed due to the rough and dangerous terrain they are built to ride on at more average speeds. 

With such exciting racing and riding conditions, the fastest bike isn’t always the best choice. The best riders choose their bike based on best fit, comfort, and their ability to manage the size of the bike and the power they give out. I bet that still doesn’t stop you from wanting to know how fast the bikes go! 

Read on below to find out more information on how fast motocross bikes can go. 

How Fast Can a Dirt Bike Go?

The capacity of a motorcycles engine, in other words how much power it has, is measured by cubic capacity (cc). Essentially, the greater the cc means more power to the bike, which means a faster bike.

Dirt bikes can start anywhere from 50cc and go as high as the rarely seen 685cc. 

Bikes starting at 50cc are usually for children aged between 3 and 7 as it’s a smaller made bike with a smaller engine with speeds of only up to 40mph. 

If you felt that you could handle speeds that exceed 110mph on a motocross track, you’d aim for the 685cc bike that you’ve probably never seen on a track before. And for good reason. Those kinds of speeds might be best left for road driving depending on your state laws and whether it’s legal. 

The best-known championship events host races for 250cc and 450cc bikes as anything over the 500cc range is too powerful even for the world’s best motocross racers. 

250cc bikes can get as fast as 55- 70mph while their big brother at 450cc can reach up to 87mph. 

Here is a simple list to break it down for you in terms of age and what bike size might suit dependent on your height. This table does not include all the dirt bike sizes that are available to you. 

This table is designed to be based on the average height and bike size for that height. It doesn’t take into consideration your experience level. Keep in mind that if you’re a first-time rider as an adult, you might want to start with a smaller cc bike, even if it’s recommended as a teenager’s model. 

Does the Size of a Dirt Bike Make it go Faster?

When choosing the size of your dirt bike you want to choose the size based on how it fits you and what your experience level is, not centered on how fast it might go. 

You could purchase the fastest bike in the store but if it’s too small or big for you, there’s not much point in having it is there? It’ll look nice in the garage though.

Adult bikes are typically in the 230cc to 450cc range while younger adults or children might ride anything from 50cc to 150cc. 

There are some details to take into consideration when discussing what makes a dirt bike go faster:

• The greater the cubic capacity (cc) the faster the bike.
• The lower the cc the slower the bike. 
• Some smaller dirt bikes can come with 110cc engines. 
• The heavier the load on the bike, the slower the bike performs. 

Motocross riders are some of the fittest sportsmen and athletes in the world. The physical and mental endurance they go through to perform well in a race is undeniably as rough as the trails they race on. 

Two-Stroke or Four-Stroke?

I feel it’s only right to mention something about two-stroke vs four-stroke dirt bikes. Depending on your riding style, both two-stroke and four-stroke dirt bikes have their advantages. 

Two-Stroke features:

• Hard hitting power band.
• Lighter than four-stroke engines.
• Because of their lightness, they typically accelerate faster than a four-stroke engine. 
• Can be harder to ride with more regular gear changes.
• Require pre-mixing of oil and fuel.

Four-Stroke:

• Has a smooth, and consistent power delivery.
• More durable than two-stroke as they don’t wear out as fast. 
• More complex design than the two-stroke engine.

What are the fastest Dirt Bikes in the World?

There are numerous companies that have designed and manufactured some of the best dirt bikes in the world. The bikes we’re about to list are irrefutably some of the best made and designed dirt bikes you will have come across. 

Here is a list of the fastest motocross bikes in the world:

KTM 450 SX-F 449cc

Ridden by world-class rider and champion motocross supercross racer Ryan Dungey, the KTM 450 SX-F provides top engine power and is one of the best dirt bike performers on today’s market. 

With speeds up to 123mph and immediate engine responsiveness, this 449cc engine is probably, as far as we know, the fastest motocross bike in the world. 

Beta 450RS

Reaching a maximum speed of 110mph, the Beta 450RS is high on the list of the fastest motocross bikes. 

The Beta 450RS takes just over 5 seconds to gain 60mph is street-legal in America’s 50 states. It has mirrors that can be folded in so if you’re using it for dirt bike riding no one would ever know it’s a street-legal bike. 

Honda XR 650cc

Also reaching speeds of up to 110mph, if fast is what you’re looking for, the Honda XR has you covered for speed. 

Designed in Japan, this four-stroke engine is built for racing long-range desert-type races. Although introduced in 2000 the Honda XR 650cc is still a much loved and sought-after dirt bike around the world. 

Conclusion

Although speed isn’t the most important component of motocross riding, it is useful to know some basic motocross sizes and average speed information. When choosing a bike, your size and height compared to the bike matters the most, not how fast the bike goes on paper. Remember, it’s not the size of the bike that counts but how you use it.