Diamond J Customs
Specializing in Quad-Rodding and Suspension Kits
Javascript DHTML Drop Down Menu Powered by dhtml-menu-builder.com

TRX 90 to 300EX Dual A-arm Suspension System Conversion

Order Now - Dual A-arm Conv. Kit and Rear Shock Conversion Kit  $200.00 incl. S&H

Click here for demonstation of the suspension travel!

There is nothing more exciting to the Honda mini-quad owner than what this kit allows you to do!!!  This kit is "Quad Rodding" at its best!  This is an awesome upgrade to the suspension, and a lot of fun to put all the pieces together.  Below we will list all of the 300ex components you will need to complete the conversion, and we'll even link you to one of the best eBay sellers out there that sells these parts virtually every week.

Most owners are unhappy with the stock performance of the TRX90 suspension, especially for a small rider. Like other small ATV’s, the jarring nature of the stock suspension can cause young riders to sometimes lose control. We do have a lower priced kit for the TRX90 listed under Widening and Shock Conversion Kits that allows for more suspension travel, and also makes the quad wider and more stable.  This kit does this too, but with the dual a-arms and disk brakes, it takes the suspension to an incredible level far above anything available to any quad smaller than a 250.  This is a SERIOUS UPGRADE, you will be impressed!!!!

This kit includes all of the conversion components to be able to use the complete suspension and brake system from a 300ex.  The shock conversion kit to relocate the top shock mounts is also included to make this a complete package (all that is needed are the 300ex components listed below).

There are a couple of reasons we fitted this kit for the 300EX components instead of parts from a 400, 450 or any other ATV's suspension.  First, there are more 300EX's being torn down for parts and sold on eBay, than any other ATV made.  We're not just talking about the a-arms, we are talking about the a-arms, spindles, hubs, brakes, etc that are needed to make this conversion possible.  If you spend some time seaching eBay, you will find that no other model has the number of components available on eBay like the 300ex (period).  Also, the 400, 450 components are in stronger demand (nearly twice as expensive on eBay) because they are used for repairing ATV's that are often raced or otherwise abused.  The 400 and 450 components are also considerably larger and an even more extreme upgrade for a mini-quad (possibly too extreme).  Even though the 400EX components will fit, we found that the 300EX components just look and work like they belong on the TRX90's.  The ultimate race setup would be to use all of the stock 300EX components except for adjustable "WORKS" 300EX shocks that you could tune exactly to your rider's weight and driving style.  We get asked the question all the time "Can I use this kit with 400 or 450 shocks?"  The answer is no, these shocks are much longer than the 300EX shocks, and there is just not that much room under the fenders!

We want to make this as easy as possible for you, so we have listed all of the Honda 300EX components you will need (they are grouped to match how they are generally listed in eBay auctions, and we've even listed the prices that we paid for two of our sets so you can get an idea of the cost and help you know when you see a good deal):

  • A set of upper and lower A-arms ($49 & $67)
  • Left-hand and right-hand brake calipers (usually sold separately) ($21 & $18; $20 & $16)
  • Front brake lever, master cylinder and brake lines ($27 &  $24)
  • Front spindles, hubs & rotors ($34 & $28)
  • 300ex or 400ex tie rod ends ($21 & $20)
  • 400ex tie rods (you can possibly get them with the tie rod ends included)
  • 300ex shocks ($75 & $81)
  • front wheels and tires from a 250EX, 300EX, 400EX or 450R ($89 & $104)  (We actually recommend buying new wheels and tires listed below for best appearance and performance.)

For us, this came to a total of $334 for the first set of components, and $360 for our second set.  Keep in mind, you will be able to sell the stock components you take off of your TRX90 on eBay to offset some of the cost.  Many customers have told us that they purchased all of the other components for less than $250.


Maintaining the power and speed levels of your ATV after the conversion is usually important.  By this, we mean they are the closest to the original tire diameters, while adding a little height.  This maintains the power and reduces the amount of trimming of the front fenders to allow the tires to clear when you turn.  While the wheels and tires listed above are the least expensive solution, here is what we found to work the best (you can use your stock rear wheels and tires):

     Front - 20x6x10 Kenda Klaws on 4x144 bolt pattern wheels (we paid $180 a pair with shipping)

     Rear - 18x10x8 Kenda Klaws on 4x110mm bolt pattern wheels (we paid $180 a pair with shipping)

               To use 4x110mm wheels on the rear of a TRX90 requires our bolt conversion kit to convert

               from the stock 4x85mm.  With this kit installed, you can also use our 2 inch 4x110mm wheel

               spacers to widen the rear to match the front.

Stock components for the quads listed above can easily be found on eBay anytime. And like we stated before, if you have this kit, you could get the after-market 300EX shocks from "WORKS" that can be specially valved for different riders. Most "WORKS" brand shocks can be re-valved even if you buy them used on eBay.

Here is a link to an eBay store for Elite-Performance-Racing where we get all of our used Honda components.  They are very honest sellers, they pack the items well, and they ship the items very quickly.

We have sold hundreds of these kits, and they ARE designed and used for the harsh conditions of motocross and GNCC racing.  They have been designed to make them as easy to assemble and strong as possible for the demanding conditions they need to survive. We will continue to test and improve these kits, and we appreciate all of the photos and positive comments that have poured in from customers (keep them coming, along with your comments on how you think they can be further improved). The unique design of the mount brackets allows the kit to bolt up to the ATV without removing any of the stock components, including the supports for the front fenders.  We do have a picture of a possible small modification that might need to be made on the 2006 and later TRX90's front fender mounts.

- This kit requires no cutting or welding on the frame, and can be installed in a weekend for a typical home mechanic.  For us, this is the most fun part, because it adds such a custom look to the quad, and puts you in the "custom bike builder" role.  To install the 300ex brake lever, you will need to grind off the mounts for the stock brake lever and bolt it next to it.

- Steel is precision cut with a LASER for accuracy. All brackets are 1/4" thick steel and bolt together for multiple thickness strength.

- All the mounting hardware shown is included (components bullet-listed above not included). The hardware uses nylon insert-collar lock nuts to resist vibration and prevent loosening of the assemblies. We've never had to retighten a piece of hardware on any of these kits even after running motocross races for months.

Before and after pictures below:

| Home | About Us | All Products | Widening Kits | Shock Conv & Lowering Kits | Youth Conversion Kits | Wheel Spacers |
| Bolt Pattern Conv Kits | ATSki Conversion Kit | Misc / Parts | Assembly Instructions | ebay Store | Contact Us |

Copyright © 2009 Diamond J Customs, all rights reserved
Designed by NDTC