How Fast Does a 40cc Dirt Bike Go? – Top Speed

Written by

James Stevens

Fact-checked by

Robert A. Verdin


How Fast Does A 40cc Dirt Bike Go

It’s amazing how fast dirt bikes can go, but as a parent or guardian, you want to think about your child’s safety. So how fast does a 40cc dirt bike go? The average speed of a 40cc dirt bike is 15 to 22 miles per hour, although some can reach up to 27 mph.

Just like other models with higher cc, there are factors that affect the speed of your 40cc dirt bike, such as its engine type, the kind of terrain, and the rider’s skill.

Thus, if you want to know all about the 40cc dirt bike and its top models, check out the discussion below!

Average Top Speed of 40cc Dirt Bikes


A 40cc dirt bike, also known as a pocket bike, is ideal for kids aged up to 13 or riders weighing 160 to 165 pounds.

Being a kid’s dirt bike, the average speed of a 40cc dirt bike is only 15 to 22 in mph. However, there are claims that this dirt bike can go as fast as 27 mph!

40cc Dirt Bikes’ Speed Based on Models and Engine Size

1. X-Pro 40cc mini dirt bike


This 40cc off-road mini bike features a 4-stroke engine with 100 RPM and a twist grip throttle. Lightweight and ideal for small kids, this bike can reach a full speed of 22 mph.

2. XtremepowerUS 40cc Pocket Dirt Bike


The XtremepowerUS 40cc Pocket Dirt Bike has a 4-stroke engine and offers stability for off-road riding, as it has low-pressure tires and a sturdy metal frame. Its top speed is 27 mph.

3. FRP DB003 40CC 4-Stroke Kids Dirt Off-Road Mini Dirt Bike


With a 4-stoke engine, the FRP DB003 40CC provides young riders with enough power and balance. Little riders can go as fast as 20 mph, and its compact size makes it easier to control and handle.

4. X-PRO Cyclone 40cc Kids Dirt Bike


Also featuring a 4-stroke engine, the X-PRO Cyclone 40cc Kids Dirt Bike is a gas-powered dirt bike that can handle riders up to 80 pounds. It has a seat height of 23.52 inches and a maximum speed of 22 mph.

5. 40cc Premium Gas Pocket Bike 2-Stroke


One of the rare 40cc dirt bikes with a 2-stroke engine, this model perfectly balances fuel economy and fast riding experience. FYI, it can reach over 30 mph and support up to 290 pounds.

Factors That Affect 40cc Dirt Bike Speed

1. Weight of the rider


If your kid is on the heavy side, they may not easily reach its top speed because the bike requires more power.

3. Type of terrain


If the rider wants to go faster or reach the 40cc dirt bike’s maximum speed, they must ride on smooth terrain or level ground such as a parking lot or driveway.

4. Engine type


Generally, a 2-stroke engine can reach a higher speed than its 4-stroke counterpart. In a 40cc bike, the former can go over 30 mph, whereas the latter can only reach 27 mph at most.

5. Rider’s skill


How fast a rider can go will eventually depend on their skills. If your child is a beginner, it’s safe to say that they can’t immediately reach the top speed of a 40cc dirt bike.

How to Reach the Top Speed of a 40cc Dirt Bike

1. Proper tire pressure

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Maintaining the right tire pressure for your child’s dirt bike will help make the ride smoother, ensuring better traction and stability.

2. Use the correct gas type


To properly power the engine for a high speed, always check what type of fuel your dirt bike requires, as there are several options available on the market, such as high-octane, low-octane, regular, mid-grade gas, etc.

In most cases, a 40cc dirt bike prefers such as high-octane gas.

3. Clean air filters


Proper dirt bike maintenance will allow the 40cc dirt bike to attain its optimal performance. An air filter without dust and dirt will let the engine run faster.

4. Upgrade exhaust system


Upgrading the 40cc dirt bike’s exhaust system will help improve gas flow, allowing your engine to run much smoother and faster. Typically, it will cause the dirt bike to increase its speed by 10 mph.


So how fast does a 40cc dirt bike go? To jog your memory, most can run 15 to 22 mph, with some exceptions that can go as fast as 27 mph or more. Now that you know these bikes’ average speed range, you can find one suitable for your child’s skill level and preferences.

We hope the discussions above help you choose the right dirt bike for your young ones!

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James Stevens

James Stevens is an expert bike mechanic who knows everything from basic repairs to custom modifications. What sets him apart is his ability to explain complex concepts in a way that's easy to understand. Check out his content on Speedway if you need help with upgrades or modifications for your bike.