Honda 300ex Top Speed, Specs, and Features

Honda 300ex Top Speed
Image: Seth Shadwick On YouTube

Are you in search of a top-tier all-terrain vehicle for trail riding and racing? Looking for an all-around ATV that is beginner friendly and also suitable for experienced drivers? Well, you’ve come to the right place. In this post, we look at the Honda 300EX, its features, specs, history, and much more.

Honda 300EX History

In 1993, Honda launched the 300EX as a replacement for the successful TRX 250X sport ATV. As one of the best trail-riding ATVs, the 300EX came with an additional 36cc of displacement and electric starting. 

Also known as the Fourtrax 300EX, it has a SOHC single cylinder 4 stroke air cooled engine capable of displacing 281.7 cc. Available with a 5-speed transmission and reverse gear, the ATV had a manual clutch and double wishbone suspension.

Thanks to this suspension system, drivers enjoy a smoother riding experience, especially on bumpy roads. This is because the suspension system does not affect wheel alignment, unlike the single wishbone system. In fact, the suspension system keeps the wheel aligned almost perfectly regardless of the terrain. Basically, the system allows for extremely good on-road manners.

However, in 2008, Honda discontinued the 300EX in name only. Today, they offer virtually the same ATV but it’s now under the brand TRX 300X.

The new version is available with the same 282 cc 4-stroke engine but the newer models do not have the headlights mounted in the front of the handlebars. The design is also sportier and offers a similar comfort level to the original.

Honda 300ex Specs

AttributesSpecifications
ModelTRX 300EX
Year1993
Model NameFourtrax 300EX
Engine typeSOHC single cylinder 4 stroke air cooled
Valve trainOverhead camshaft – chain drive
Bore74 mm (2.9 inches)
Stroke65 mm (2.6 inches)
Displacement281.7 cc (17.2 ci)
Horsepower21 hp (21.3 PS)
Starter TypeElectric
Transmission type5 speed with reverse
Clutch typeManual
Gear shift patternR/1 – N – 2 – 3 – 4 – 5
Voltage12V
Power typeDC
Regulator Voltage14 – 15.5 V
Front suspensionDouble wishbone
Rear suspensionSwingarm

Honda 300ex Features

As aforementioned, Honda replaced the 300EX in 2008, and today, it’s available under a different brand name – TRX 300X. However, the specs of the newer model are similar to the original.

Engine

The Honda 300EX comes with a 4-stroke engine capable of displacing 281.7 cc and producing 21 hp. Honda was the first car manufacturer to build the single-cylinder SOHC air-cooled engine for the 300EX. This explains why the ATV is beginner friendly and pro-compatible.

Suspension

The front suspension of the ATV is a double wishbone while the rear suspension is a swingarm. When driving the ATV, the front wheel can travel 170 mm (6.7 inches) while the rear wheel can travel 200 mm (7.9 inches).

As aforementioned, the double wishbone suspension offers a smoother driving experience. This is unlike single wishbone suspension systems that affect wheel alignment.

Tires

The front tire size is 22 inches (height) by 7 inches (width) with a rim size of 10 inches. The rear tire size is 22 inches (height) by 10 inches (width) with a rim size of 9 inches (diameter). 

Thanks to their construction, they provide a smoother ride and lower rolling resistance. In addition, they improve tread life and handling. In fact, they do so by almost 50%.

Ergonomics

The ATV is an all-purpose vehicle that comes with roomy and supportive seats and a broad handlebar for easier control. In fact, you can maintain steering control whether you’re a beginner or an experienced driver.

Honda designed the ATV’s footrest to provide comfortable support when you drive. In addition, they fitted the ATV with a double wishbone suspension system for a more comfortable ride. As such, the ATV can travel over uneven terrain with ease.

Brakes

The front brake type is a dual hydraulic disc while the rear brake type is a hydraulic disc. With the hydraulic disc brakes, you are always assured of more stopping power and less frequent maintenance. This is because the brakes self-adjust.

In addition, the brakes will have a smoother operation because there is less friction in the system.

Drivetrain

You can get the 300EX as a 2WD or a 4X2 driveline. However, drivers can only engage one of these systems at a time. The 300EX chain is lightweight and secured to an O-ring sealed chain. For easier movement, forward or backward, the ATV comes with a 5-speed gearbox with reverse and a manual clutch. Together, these parts allow the driver to drive the ATV forward or backward by efficiently transmitting power to all the wheels.

Seats

The 300EX comes with a one-piece seat made of vinyl. It has a height of 30.3 inches (769.6 mm) and built to offer the driver and front rider a comfortable experience.

The seats have a curved shape that supports the thighs and back. It also comes with a headrest to ensure the front rider enjoys an optimal level of comfort. To provide additional comfort and support, you can add seat cushion. Besides comfort, the seats come with safety belts for the drive and front driver. This ensures they are safe while driving the ATV.

Fork

The Honda 300EX is an all-terrain vehicle built to endure bumpy roads, trails, and much more. To ensure the driver can travel over a variety of terrains, Honda fitted the 300EX with a front adjustable fork preload.

Made of durable and long-lasting materials, the front fork allows the ATV to endure the demands of off-roading. Engineered to fit onto the 300EX, this important piece of machinery protects the ATV’s front from damage. It also ensures the driver and front rider have a pleasurable ride.

Control and Handling

Honda designed the 300EX for racing thanks to its powerful engine and lightweight chassis. Simple to operate, the ATV’s broad track offers grip and stability regardless of the terrain.

The front and rear suspensions are adjustable and allow any driver to personalize their driving experience. To provide high stopping power, Honda fitted the ATV with hydraulic disc brakes. In addition, they connected the rear brake to the throttle. By doing so, they made it easier for the driver to manage the speed of the 300EX.

Gas Mileage

While the Honda 300EX is for racing, you can expect an average of 20 miles per gallon. Even when you get a 300EX that’s old, you can still get the same miles per gallon as a brand-new 300EX. However, it depends on the maintenance and care given to the ATV.

When it comes to maintenance given to the 300EX to keep it working, the ATV only needs the basics. You can carry out regular checks on the oil and change it per the manufacturer’s instructions. By doing so, you ensure the oil is not running low or contaminated.

Besides changing the oil, make sure the air filter is also changed or cleaned frequently.

Honda 300EX Top Speed

The Honda 300EX is a four-wheel drive ATV suitable for both beginners and experienced riders. During its 17 years manufacturing cycle, the ATV maintained its sporty design.

A Honda 300EX can go above 55 mph. In fact, it can easily reach up to 60 mph with a rev limit increase. However, a stock 300EX is mechanically limited to 55 mph. On a straight road, the 300EX can reach 54 mph whereas, on a dirt road, the top speed will decrease by 5 to 8 mph.

With gear change, it’s possible to drive the 300EX to speeds of up to 60 mph. Over normal terrain, the ATV can reach speeds of up to 50 to 52 mph.

You might also like:

Most Common Problems With Honda Big Red UTV

Yamaha Yz250f Top Speed: All You Need To Know!

Hisun Strike 550 Top Speed, Specs, and Features (Explained)

Yamaha YZ125 Top Speed, Specs, And Features

How to Increase the Honda 300EX Top Speed Without a Limiter?

There are several ways to increase the Honda 300EX top speed even without a limiter. The first thing you need to do is change the sprockets that come with the ATV. Also known as chain wheels, the sprockets are usually made up of several teeth.

To adjust the drive ratio, adjust the diameters of the front and rear sprockets. Then, divide the numbers to arrive at the best ratio. According to experts, the best ratio for the Honda 300EX is 14/34 which can increase the speed of the ATV to 65 kph. 

If you adjust the front sprocket teeth to 15 and 36 for the rear sprocket, you can increase the speed of the ATV by 70 kph.

Next, upgrade the engine by altering a couple of components in the existing engine. Such components include the crankshaft, cylinder, and piston. By changing these components, you can boost the effectiveness of the ATV.

However, the best course of action is to buy a new engine. This is highly recommended if you don’t have the skills to disassemble and reassemble the existing engine. We recommend that you hire a professional mechanic.

After you change some of the components of your engine or buy a new one, the next step is to check the airflow. Improving the airflow will get you more power. After improving the airflow, make adjustments to the exhaust system. What you need is to look for the best aftermarket exhaust. This will improve your ATV’s performance and cut down on weight.

Lastly, replace the heavy parts, especially the copper-based components. These heavy parts increase the aerodynamic drag and decrease the ATV’s speed. However, if you replace the heavy parts, you increase the ATV’s speed and reduce the amount of aerodynamic drag.

Frequently Asked Questions

Is a 300EX good?

Yes, the Honda 300EX is good. It comes with a powerful and easy-to-handle engine, great handling, and excellent suspension. This ATV will get you driving down trails, jumping bumps, and railing around corners.

How big is a Honda 300EX gas tank?

The gas tank for the Honda 300EX has a capacity of 3.2 gallons.

What kind of spark plug does a 300EX take?

The 300EX takes the NGK standard spark plug, a workhorse designed for the smooth-running engine of the ATV.

What oil does a 300EX use?

The 300EX takes 2 quarts of Honda GN4 10W-40 4-stroke oil.

Does Honda still make the 300EX?

No, Honda discontinued the manufacturing of the 300EX in 2008. However, they are manufacturing a similar ATV with the same specs and features called the TRX 300X.

How much horsepower does a 300EX make?

The 300EX can produce 21 hp and a displacement of 282 cc thanks to the powerful engine.

Is a Honda 300EX a 2-stroke?

No, the 300EX is not a 2-stroke. It comes with a SOHC single cylinder 4 stroke engine with electronic ignition.

Does a Honda 300EX have a clutch?

Yes, the Honda 300EX has a clutch, a manual one just like the 250X, 400EX, and 450R.

How fast does a Honda 300EX go?

The 300EX can reach speeds of up to 55 mph. However, with a few upgrades to the engine and changes to the sprockets, the ATV can reach speeds of up to 65 mph. You can install an aftermarket exhaust allowing your ATV to reach speeds of up to 70 mph.

How much oil does a Honda 300EX take?

The Honda 300EX can take 2 quarts of oil.

How to tighten the chain on a Honda 300EX?

To tighten the chain on a Honda 300EX, locate the two Allen head screws at the back of your swingarm. Loosen these crews and then behind the rear sprocket, you’ll find a round thing with slots. Insert your Allen wrench and then rotate it back. Once you achieve the desired tension, retighten the Allen screws.

How to time a Honda 300EX?

Take off the caps and your valve cover. This will allow you to see the cam. Put a socket wrench in the middle screw hole and turn the bolt until you see three marks on the freewheel. You need to line the middle mark on the thread of the screw hole.

On the opposite sides of the cam sprocket, you’ll see two marks opposite each other. If the markings are not even with the engine’s top, your timing is off. To time your Honda 300EX, loosen the timing chain tension.

Does the ATV Honda 300EX have reverse gear?

Yes, the 300EX has reverse gear.

Final Words

The Honda 300EX is an excellent ATV. Although they discontinued it in 2008, you can find used models for racing, and trail riding. With basic maintenance and upgrades, a used 300EX can reach speeds of up to 52 to 70 mph. So, if you’re looking for a sturdy mid-sized ATV that’s beginner friendly and suitable for experienced drivers, then we recommend the 300EX.