As in previous years the forks are a 43mm air fork asymmetrical arrangement. One fork leg is the air leg taking care of main spring functions and the other leg takes care of the damping character. In general, the forks are a carryover from 2024, not much to report here however there are several options for you to consider...

If you are not a fan of an air fork there is a Factory Connection spring kit that takes care of you there, the forks remain an asymmetrical scenario, spring in one leg and OEM damper leg on the other side, no more checking air pressure, easy...

There is a cartridge kit available that is made by WP (Xact Pro 6500 Cartridge) which turns the forks into a "normal" spring fork meaning there is a spring in both the left and right fork leg along with a damping cartridge in each fork as well.

Of course, you can go all in and jump up to the Xact Pro fork (Xact Pro 7543) made by WP which is the top-of-the-line solution giving you symmetrical closed cartridge cone valve technology. www.wp-suspension.com/xact-pro/

Factory Connection spring kit, WP 6500 CTG Kit and WP XACT-PRO forks.

Front Engine Mounts:

There is a new chassis made of high-strength chromium molybdenum steel, the new layout has changed the rear motion ratio and there is a new one-piece construction swingarm, several things on the rear shock have also changed, more on that later.

The steering head angle is 63.5° which is 1/2 degree less than the previous generation. The steering head is also 6mm closer to the rider, KTM is saying this creates a more stable front end. The steering turning angle (left to right) has been increased by 2° for a total of 35° now, for tight corners this can help being able to turn the front wheel more than in the past.

The rear shock mounting point is not part of the upper frame tube rather it is an additional fixation point which is part of the change to the flex characteristic of the frame. The engine was rotated upwards 3° compared to previous years, this change was made to compliment the new frame character and generate a good balanced feel. The rear shock has less stroke than last year, KTM's goal with that change is to increase traction at the rear wheel.

The new swingarm is now a one-piece construction with emphasis placed on the torsional rigidity (how much it twists), this is matched to the new frame for the overall feel of the bike. The new swingarm starting point is 2.3° flatter. Ergonomically the rear portion of the seat is lower than the previous generation, this is again focused on rear traction (flatter swingarm angle, lower rear seat allows the rider to hang off the back and work in a better part of the swingarm angle) www.youtube.com/watch?v=1IqHqJ2F9pk

2025 KTM85SX

This is where some of the bigger changes are to the suspension package. The rear shock is shorter; without talking to KTM engineers we are assuming this is part of making the starting point of the swingarm flatter contributing to the new found rear traction improvement. The rear motion ratio we are assuming is quite different given the amount of rear wheel travel versus rear shock travel, however we have not confirmed this yet...

Another tell is that KTM went up on rear spring rate while specifying a lighter intended body weight, it would seem with all of that the motion ration has changed to something offering less leverage, all good, que the horn for the suspension companies to jump in as needed to match previous year's custom revalve performance.

The 2024 piston is on the left and the 2025 piston is on the right. You can see a new metal piston ring that has replaced the fiber style band.

The shock main shaft piston has changed for 2025, shown above you can see the 2024 piston on the left and the 2025 piston on the right. You can see a fairly significant change to the compression side of the piston, the shape and how the holes are arranged have a big impact on damping character.

Here we can see the rebound side of the two shock main shaft pistons. The 2024 piston is on the right hand side and the 2025 is on the left, this is showing the rebound side of the piston. Similar to the compression side new geometry here will change the shock performance.

In order for us to create your settings we look at several different aspects of a chassis and the suspension. Focusing on the suspension part we record layout info like lengths and strokes, we rate the springs in detail looking for anomalies, design and produce a line of springs with as many or more options than the OEM.

Dyno work happens to record the OEM performance and then we work on generating many different solutions for various types of riding be it off-road, motocross, supercross and more.

Field testing happens to make all the final choices that were estimated in the shop using theory, make no mistake the final answer is only good once it gets a thumbs up from riders out on tracks.

At times we hit road blocks and in order to solve them we create new parts that eliminate the obstacles in the tuning path. When all is said and done there are several hundred-man hours put into making a new model come to life with settings and products. Here are a few pictures of that work in the background...