How to Make a TRX 90 Faster: 6 Simple Methods!

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The Honda TRX 90 is not very fast. But the speed is kept limited intentionally. But sometimes the TRX 90 can be turned into a faster ATV.

So, how to make a trx 90 faster? 

The most popular way is to perform the pink wire mod which removes the speed limiter in 4th gear. Other options are modding to reduce weight so the vehicle becomes faster.  Upgrading the throttle and exhaust is another way to make your TRX 90 fast. You can also try to upgrade the engine with the big bore kit, or remove the airbox. 

By the end of this article, you’ll understand how to get the most out of your TRX90 and take your off-road adventures to the next level. So, let’s head in!

The Actual Top Speed of TRX 90

The top speed of a stock Honda TRX 90 ATV with a 90cc engine is typically around 23 miles per hour (37 kilometers per hour). However, it is important to note that the top speed can vary depending on driving conditions and the condition of the vehicle itself.

Always remember that a properly driven ATV will reach higher speeds even at an older age. 

Factors such as terrain, and wind resistance can all affect the top speed of the ATV. Additionally, if the vehicle is not well-maintained or if there are mechanical issues, this can also impact its performance.

That being said, it is possible to increase the top speed of a TRX 90 to around 50 MPH (80 KPH) with the right adjustments and modifications.

It is important to note, however, that making modifications to your ATV can affect its safety and reliability. However, remember to maintain safety and caution at all times.

The cautious speed limit makes the TRX 90 very popular for kids. But there are other ATVs available for children.

Top Speed of TRX 90

How to Make the Honda TRX 90 Faster?

There are many ways to increase the speed and driving enjoyment of the TRX 90. Some you can do at your home, and some you must go to a mechanic for assistance.

Reducing Weight:

Reducing the weight of an ATV can help increase its speed.  When the ATV is heavier, your engine will need to make an extra effort to get the wheels moving from a stationary position. You may not be able to spin tires in mud as effectively, either. 

If your main goal is to drive in the mud, there are ATVs especially made for muddy terrains

There are several ways to remove weight from an ATV. 

  • Change the body kit
  • Remove the front and rear racks, 
  • Replace the stock exhaust with a lighter aftermarket exhaust, 
  • Replace the stock battery with a lighter lithium-ion battery, 
  • Replace the stock wheels with lighter wheels 
  • Remove any unnecessary accessories

Pink Wire Mod:

Performing the “pink wire mod” on a Honda TRX 90 involves bypassing the 4th gear speed limiter. This modification can improve the vehicle’s ignition timing and allow it to reach higher speeds in 4th gear.

Here is a general procedure for performing the pink wire mod on a Honda TRX 90:

Step 1: Locate the CDI unit on the ATV. You can find this under the front plastic cover or the seat of the ATV.

Honda TRX 90
Source: YouTube

Step 2: Remove the CDI unit from its mounting bracket and disconnect the wiring harness from the unit.

Step 3: Locate the pink wire on the wiring harness. This wire is usually easy to identify because it is the only pink wire in the harness.

Step 4: Cut the pink wire and remove the insulation on both ends.

Step 5: Connect the two stripped ends of the pink wire together using a butt connector or wire splice.

Step 6: Reconnect the wiring harness to the CDI unit and remount the unit in its bracket.

Step 7: Now test ride the ATV to verify that the pink wire mod has been successful and that the 4th gear speed limiter has been bypassed.

NOTE: It is important to note that performing the pink wire mod can have safety implications, and it might be illegal in many areas. 

Additionally, this modification can potentially damage the engine or other components if not done correctly. So, consult with a professional mechanic before making any modifications to your ATV.

Throttle Upgrade:

Upgrading the throttle on a Honda TRX 90 can help increase the vehicle’s top speed by improving throttle response and allowing the rider to achieve a higher level of acceleration. A high-performance throttle kit can also allow for finer adjustments of the throttle, resulting in a more precise and consistent ride.

Here is a general procedure for upgrading the throttle on a Honda TRX 90:

Step 1: Remove the factory throttle assembly from the handlebars of the ATV.

Step 2: Install the new throttle assembly onto the handlebars. You can easily do this by following the instructions provided by the manufacturers.

Step 3: Connect the throttle cable to the new throttle assembly, making sure that it is securely fastened and properly routed.

Step 4: Adjust the throttle cable tension so that there is a small amount of slack when the throttle is closed, but the cable is taut when the throttle is opened.

Step 5: Test the new throttle assembly to ensure that there is no issue while functioning, throttle response, or sticking.

NOTE: While upgrading the throttle can help increase the top speed of the ATV, it is not a guaranteed solution. And other modifications may be necessary to achieve significant gains in speed.

Additionally, consult with a professional mechanic to ensure that the throttle upgrade is installed correctly and safely. Also if the instructions are not that clear then you can check this video for detailed instructions.

Remove the Airbox: 

Removing the airbox can help increase the speed of your TRX 90 by allowing more air into the engine. The airbox is designed to slow down the flow of air and spread this air totally across the air filter while cutting down noise. 

By removing the airbox, you’ll effectively increase the volume of air that goes into the engine. This can increase the power output of the engine. 

However, removing the airbox can also allow more dirt and debris to enter the engine, which can cause damage over time.

Here are the general steps for removing the airbox on your TRX 90:

Step 1: Remove the seat and gas tank.

Step 2: Remove the airbox cover and filter.

Step 3: Remove the airbox from the frame.

Step 4: Install the new air filter onto the carburetor. You will need to adjust the carburetor as well for this process. 

Step 5: Install the new air filter onto the frame.

These mods are better visualized than instructed and that’s why here’s a video to assist you.

Exhaust Upgrade: 

A performance exhaust system can help increase the top speed of your TRX 90. It is done by increasing the airflow and power output of the engine. 

The installation process for a performance exhaust system will vary from system to system. Here are the general steps for installing a full system exhaust on your TRX 90:

Step 1: Remove the nuts securing the head pipe to the cylinder head. Save these nuts, they will be reused to install the HMF exhaust.

Step 2: Remove the support bolt in front of the silencer.

Step 3: While bracing the silencer remove the bolt securing it to the frame, then carefully maneuver and remove the stock exhaust from the machine.

Step 4: Install the HMF exhaust in reverse order of removal.

The cost of a performance exhaust system can vary depending on the brand and type of system you choose. 

Big Bore Kit: 

A bore kit upgrade is an engine modification that increases the engine displacement and power output. The Honda TRX 90 is available with a 114cc bore kit upgrade which will increase the engine displacement from 90cc to 114cc. And provide a significant increase in power output.

Big Bore Kit 

This is a quick and easy upgrade that can make a huge difference in performance over your stock setup1.

The installation process for a bore kit upgrade can vary depending on the specific kit you choose. Here are the general steps for installing a bore kit upgrade on your TRX 90:

Step 1: Remove the cylinder head and cylinder from the engine.

Step 2: Remove the piston from the connecting rod.

Step 3: Install the new piston onto the connecting rod.

Step 4: Install the new cylinder onto the engine.

Step 5: Reinstall the cylinder head onto the engine.

These are the general instructions to give you an idea. But we highly recommend going to a mechanic to have the procedure done.

The cost of a bore kit upgrade can vary depending on the brand and type of kit you choose. 

Precautions Before Modding the TRX 90

There is something you must be wary of: 

  • The modifications are legal in your area 
  • Ensure that the modifications are safe 
  • Ensure that the modifications are installed correctly.
  • Ensure that the modifications are compatible with your ATV
  • Follow the recommendations provided by the manufacturers for maintenance and service
  • Do not exceed the weight capacity of your ATV.

Frequently Asked Questions (FAQs):

Does TRX 90 have an Electric Start?

The Honda TRX 90 has an electric start which is appreciated by kids and parents. The electric start is a feature that is present despite the lack of electronic fuel injection. The electric start is brought to life by a longitudinally installed four-stroke, air-cooled single-cylinder OHC engine.

Does Honda TRX 90 have a Reverse Gear?

The Honda TRX 90 does not have reverse gear. However, it is a great ATV for kids and beginners due to its compact size, electric start, and no-clutch transmission.

What does TRX stand for Honda?

TRX stands for “Trail” and “Recreation” and is a series of all-terrain vehicles (ATVs) produced by Honda. The TRX series of ATVs are designed for off-road use and are intended for recreational use.


And with that we know how to make a trx 90 faster. Some of the procedures you can do by yourself. Hopefully you won’t have any troubles doing them. 

But others will require professional help. And it is for the best if you consult a professional for those cases.

Best of luck!