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What Is The Top Speed Of A Honda 400ex? [Find Out Here]

What Is The Top Speed Of A Honda 400ex? [Find Out Here]

The Honda 400EX is an incredible Honda Motors product with impressive features designed to offer a smooth ATV riding experience. The All-Terrain Vehicle features an independent double-wishbone front suspension, an XR400R-inspired engine, and a sturdy body structure to last long. So, what is the top speed of the Honda 400ex?

The Honda 400ex boasts a 28-horsepower engine with a top speed of 72 MPH. With a sturdy steel frame and solid cast aluminum swing arms, the ATV can comfortably handle the undue pressure occasioned by the high speed on rugged terrain. Additionally, the triple-disc brakes guarantee the need for stopping force.

Generally, the Honda 400ex is one of the outstanding ATVs that are not likely to disappoint you in any situation. If you are out to purchase a Honda 400ex but feel that you need to acquaint yourself with some information, this article will be helpful.

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The Honda 400EX Top Speed

The 28 horsepower engine, a sturdy sports frame, and triple-disc brakes make it possible for the Honda 400EX to achieve a top speed of 72MPH.

Further, the Honda 400EX boasts several exciting features, including the high 397 dry-sump, four-stroke single-cylinder engine, and radial valve combustion to ensure the effective creation of horsepower.

However, those are not the only features and specs associated with Honda 400EX Specs.

The Honda 400EX Specs

  • It has an electric starter for an instant start
  • Air-cooled
  • Features an RFVC, dry-sump, one-cylinder, four-stroke engine
  • Manual clutch
  • A 5-speed with reverse transmission
  • A top speed of 72 MPH
  • 2.6 gallons with a 0.4-gallon reserve
  • The ATV weighs 375 LBS
  • Dual hydraulic 174 mm discs rear

Honda TRX 400EX Top Speed

The Honda TRX 400EX was first released in 1999 by the Honda Company. It was among the first ATVs to feature an air-cooled dry sump.

The Honda TRX 400EX Top Speed is 70 MPH on a reasonably smooth track. While the 70 MPH speed is pretty fast for most riders, if you feel that you want to increase the speed, you can always do it.

With a couple of modifications, you will have the speed of your ATV increase tremendously.

The 2004 Honda 400EX Top Speed

The 2004 Honda 400EX Top Speed, also referred to as the Sportrax 400EX, is a fantastic machine featuring a 397-cc engine, aggressive styling, pro-link rear suspension, and other incredible features that make it continue dominating the modern market.

When it comes to the top speed of the 2004 Honda 400EX, it never disappoints. The ATV boasts a top speed of 72 MPH, made possible by its strong engine and aggressive styling. If speed is among your top considerations when shopping for an ATV, the 2004 Honda 400EX will serve you right.

The 2004 Honda 400EX Features

The 2004 Honda 400EX is a game changer as far as ATVs are concerned. It was designed to eliminate various challenges experienced by the first ATVs.

The Engine

The 2004 Honda 400EX features a 397-cm3 air-cooled single-cylinder 4-stroke engine, making the 2004 Honda 400EX achieve an incredible speed of about 72MPH. Notably, the 38-mm piston valve coupled with the accelerator pump is responsible for the proper air-fuel mixture for a smooth ride.

The Radial Four-Valve Combustion Chamber and the great XR400-adopted power mill make it possible for the ATV to quickly hit a top speed of 72 MPH with a horsepower of 28 RWHP.

Lubrication And Fuel

The 2004 Honda 400EX has a fuel tank capacity of 2.64 gallons, including the 0.04-gallon reserve. For top performance, you must use Pro Honda GN4 motor oil without molybdenum or graphite additives.

To avoid pinging or spark knock, you should avoid using lower-octane gasoline. The pinging should never be a point of worry when riding under a heavy load or uphill. Nonetheless, you should worry if it occurs under normal riding conditions.


When handling a machine with the capabilities to attain an incredibly high speed, the controls become paramount. The exciting thing about the 2004 Honda 400EX is that most of its controls are situated near the handgrip to make their usage reliable. For instance, the start button, parking brake levers, clutch, stop switches, and the headlight are near the left handgrip. In the same way, the choke lever, fuel valve, and gear peddle are situated on the left side of the engine.

Further, the front brake, the front brake fluid, and the throttle levers are close to the right handgrip.

The Ignition

The 2004 Honda 400EX boasts an efficient and reliable electric starting system for breathing life into the amazing ATV.

Tires And Brakes

The 2004 Honda 400EX tires are designed to handle the rough terrain and any undue pressure you may encounter when riding your ATV. Sturdy tires have always proved critical when it comes to evaluating the efficiency of the ATV. However, if you feel that you need to modify your ATV to increase its speed, there would be nothing wrong with replacing them with more efficient ones.

The Suspension

The suspension of the 2004 Honda 400EX is enclosed in a tubular steel frame with a fully adjustable shock. With a minimum ground clearance of 4.3 inches and a turning radius of 3.2 meters, you can trust the suspension to serve you right in all circumstances.

The 2007 Honda 400ex Top Speed

The 2007 Honda 400EX boasts a 28-hp power output, a pro-link rear linkage, an air-cooled 397-cc engine, and aggressive styling. Being the 9th installment of the sport utility series from the Honda, the ATV continues to impress both professional and beginner riders.

The 2007 Honda 400EX top speed is 65-72 mph depending on the conditions of the trail and its weight. Besides the incredible speed, the 2007 Honda 400EX features an electric starter and a 4-stroke RFVC engine that brings it to life while guaranteeing an incredible performance.

Ways to Increase the Speed of your ATV

The good thing about investing in a quality ATV is that simple adjustments can quickly increase its speed. Here are some minor adjustments you can make to your ATV to boost its speed.

Clean The Air Filter

A simple task such as ensuring that your air filter is clean before going for a race can tremendously increase the speed of your ATV. Clogged air filters interfere with the airflow to the combustion chamber, thus preventing the complete combustion of fuel for energy production. In addition, you should ensure that you use better fuel.

Tire Pressure

Another recommendation to increase your ATV speed is to ensure the tires have enough pressure. Always ensure that you have quality tires that are easy to inflate. Additionally, before going out for a race, you should ensure that the tires are in perfect condition.

Besides the air pressure, it is crucial to understand that tire size can also influence the speed of your ATV. Small tires are the best when you are after an acceleration on a flat surface. On the other hand, big tires will be the most appropriate when riding on rough terrain.

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Upgrade The Exhaust

Upgrading your ATV's exhaust can also play a significant role in increasing the speed of your ATV. When waste products of the combustion can leave through the exhaust quickly, the engine can pull more air for efficient combustion. In most cases, excellent exhaust systems usually are big.

Change The Gear Ratio

Lastly, changing the gear ratio can play an essential role in enhancing its speed. Gear-up increases can increase the speed of your ATV instead of gear-down, which reduces the top speed while increasing the acceleration.

Final Thoughts

The Honda 400ex top speed is about 75 MPH. While that is a pretty fast speed, you can always carry out some modifications to increase the speed of your Honda 400EX even further. Some minor modifications that can help increase the speed of your ATV include, installing a big bore kit, changing the gear ratio, upgrading the exhaust, adjusting the throttle limiter, and many others.