Mod Squad – Active Ride Shop Suspension Modifications On The 2005 KTM 250SX


PRICE: $565 ($145 shock revalve, $155 fork revalve, $105 shock springs, $95 fork springs, $65 shock shortening)


The TransWorld testing staff has really enjoyed the 2005 250SX from KTM, but it is no secret that the suspension on the bike is a bit…well, it’s pretty harsh and unforgiving in stock trim. After several rides at some rough local tracks, we had numerous complaints about our KTM test bike’s suspension and handling. For one, the forks dove too much under deceleration, and the front end had a very vague feeling in flat corners. The bike also had a very stink-bugged feel around the track, making us think that we would launch over the bars at any moment. In short, we knew that we had to do something.

Active Ride Suspension is a mod shop out of the sunny town of Spring Hill, Florida. After hearing of our woes on the orange bike, the guys there offered to give the problem a try. We briefly described our issues and asked them to set the KTM up for a speedy 175 lb. rider.

The first modification was to soften up the high-speed valving in order to make the KTM handle better in choppy sections of the track. The mid-valve was then modified to help keep the forks up in their stroke, and to also alleviate mid-stroke harshness. Next, stiffer .46 kg/mm springs were installed with the intent of supporting the rider and further keeping the front end riding high up in the stroke.

Once the forks were finished, the Active guys dug into the shock. They first softened the primary piston, working a large amount on both the high and low speed compression valving in order to make the shock run a bit softer and have a much smoother action. The secondary piston valving was then stiffened to make the shock more stable and progressive, as well as to give it more control later in the stroke. A stiffer, 8.0 kg/mm rear spring was installed to suit a 175 lb. rider.

To cure the stinkbug feeling, the rear shock was shortened 5mm. This lowers the seat height a whopping 30mm, which also keeps the shock from over-extending in the whoops, resulting in way more stability. Lowering the seat height was also a fix for the vague feeling of the front end, because it increases trail and gives the bike more of a contact patch with the ground.

After getting the suspension back, the changes to the KTM were immediately noticeable. For one, the front-end problems were obviously a thing of the past. Not only did the front not dive, it also had a much lighter feeling to it in rough sections, and grabbed a lot more traction up front. The stinkbug stance was cured, as the bike felt very balanced all the way around the track. In fact, one of our favorite things about the Active Ride suspension was that it felt very even and did not kick in any way. Stock KTMs can have a lot of unexpected bumps and jolts, but after the Active modifications, there were absolutely no surprises. The bike also felt great in rough sections of the track, and mild chop was no problem.

We only had a few small complaints about the Active Ride suspension. First, we found the forks to be too soft for our tastes when it came to hard landings. Aggressive over-jumping and exceptionally harsh square-edged bumps made the forks blow through the stroke, sending a massive jolt to our hands. This is a problem that could be solved by either smoother riding or a more forgiving track, but we would have liked to see the forks a bit stiffer near the bottom of the stroke. Secondly, the front wheel of the KTM became somewhat harder to turn once the seat height was lowered, but this was not too much of a problem on the track, and is an easy trade-off for the extra traction that the modification brings.

Overall, Active did a great job of turning our KTM into a better-handling, more rideable machine. Each of our original complaints was handled perfectly, and the tuners were extremely knowledgeable and easy to talk to. If you ride a KTM and are lookking for a way to give it a more personal, smoother feel, we suggest getting in touch with the crew at Active Ride Suspension: they will definitely listen to what you have to say.

Call 352/428-3960 or visit