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When deciding to spend a few thousand extra dollars on suspension for your ten thousand dollar KTM/Husqvarna, you want to know if it’s going to make a difference immediately. Is it going to make me a better rider? Will I be able to ride faster with it? Do the WP’s XACT Pro Components that much better than stock? These are a few of the questions I get when the consumer is trying to make a decision on getting a set of WP XACT Pro Components. I have pounded hundreds of laps and a ton of hours on the stock WP AER fork/shock as well as the XACT Pro Components (on the 2020 KTM 450 SX-F and Husqvarna FC450) to see if it’s worth the risk of your wife losing her mind when she sees the charge on the bank statement.
What Are WP XACT Pro Components and what are the differences between older WP Cone Valve/Trax components?
WP’s Pro Components line is aftermarket suspension designed for riders who want the highest quality components and are willing to pay a reasonable amount of money for them. Pro Components are manufactured to tight tolerances using high quality materials, fine surface finishes, and low-friction coatings. This reduces friction compared to WP’s OEM suspension components, and is perhaps their most significant advantage. In fact, to achieve a similar feeling of stiffness to the OEM suspension, all Pro Components required much stiffer damping. The additional stiction in the OEM components is all due to friction. Friction is perhaps the one thing in suspension where no compromise is involved: less friction is always better. When setup appropriately for the rider, Pro Components can deliver high confidence at high speeds.
The Xact Pro fork is the next evolution in “Cone Valve” technology. It retains the same Cone Valve technology and is available in three basic variants: closed cartridge with coil springs, closed cartridge with air spring, and open cartridge with coil springs. The Cone Valve itself is nothing too extraordinary as it’s simply a shimless mid-valve. The cup-in-cone valve actuates via a coil spring, providing the variable orifice function that shims normally handle. The Cone Valve spring rate is linear, unlike shims which are more progressive. Also unlike shims, it does not have a maximum safe deflection distance. It can be setup stiffer and with less float than a shimmed valve without getting too much of a rigid handling ride.
The Xact Pro shock features an updated version of the Trax mechanism used in previous Trax shocks. WP’s Trax system is created to reduce rebound damping when the rear wheel is off the ground, helping get the tire back to traction as quickly as possible. The Trax system is now externally adjustable with a screwdriver, which makes the Trax function much easier to use and understand. The shock uses the same high-end construction as the Xact Pro fork and as a result, it sees a similar reduction in friction compared to OEM shock. It uses a nitrogen bladder instead of a piston separator, which has lower friction, but can require more frequent services compared to WP’s traditional piston separator setup. As with past Trax shocks, it separates high-speed compression and low-speed compression into two separate adjusters instead of one dual compression control (DCC) adjuster. The Trax shock shaft includes a rebound separator valve, which isolates compression and rebound adjustments, and increases low speed compression damping at the mid-valve (which can aid in pressure balance)
WP’s XACT Pro Components are usually found on all of my KTM’s and Husqvarna’s I race with. Why? I get more consistency and performance out of the XACT Pro Components than that of the stock AER fork/stock WP shock. I tested the stock suspension settings on the 2020 KTM 450 SX-F back to back with the WP Pro Components and came away with this opinion:
On The Track:
The first thing I noticed when I go out onto any type of track with the XACT fork is that the KTM turns slightly slower than the AER fork on initial lean (into corners), which is exactly what out of the KTM. The KTM does have a slightly rigid feel to it and can be a handful when riding fast, choppy tracks. You can actually feel the extra weight right away (in the front end) compared to the stock AER fork, but it wasn’t a bad feeling. I was just surprised I could feel it as much when entering corners. Usually I run the fork flush on previous Cone Valve forks, but with the slower turn in feel and a the longer length of the new style XACT fork I went with a 5mm height. Along with the extra weight feeling however I gained more front end traction through every corner (especially flat corners). The XACT fork leaves you with a more front tire contact patch sensation on lean angle and you can start your lean earlier in ruts without getting the high front end, vague feeling like you do with the AER fork. With the AER fork I get some pushing in the front end through the middle to end of corners, which made makes me roll off the throttle to try and compensate. With the XACT fork I can lean in the corner and the fork stays planted, which lets my front end settle and bite. The WP XACT fork also feels less active on braking bumps. I am able to jump in and out of bigger bumps that each track I tested at offered, without having the fork rebound too quick and be too active. If I wanted to pound through the bumps, the fork had better damping control feeling through the middle to end part of the stroke.
The most notable change was to my wrists when over jumping/flat landing with the XACT fork. I could get more aggressive with obstacles and have the bike settle into corners better in areas of the track I wasn’t able to with the stock suspension. The downside to the XACT fork is that it can make the KTM feel like it has less flex up near the head tube area. This feeling is not as rigid as a Honda CRF450R, but it does give you a firmer feel through your hands on small bumps, compared to the AER fork. The key to the WP XACT fork is getting it set up for you. WP does a great job of getting you the XACT fork with a “ballpark” setting, but going through an authorized dealer that can set it up for your personal needs is the best way to ensure your investment works the best. I tested the XACT fork with their customer setting and although it was better than stock, I could have used a little more hold up on hard braking or when their was deeper braking bumps.
The XACT shock holds up better than the stock shock for me on high speed compression and you are able to get more aggressive around the track. I can hit the faces of jumps harder and the KTM did not give me an empty/low feeling sensation that the stock shock sometimes gave me. In order to combat that feeling with the stock shock I would have to crank in the high speed compression so much that I would lose the comfort coming out of corners (and rear wheel traction). The XACT Pro shock provides you with more high-speed damping and you still get a decent amount of acceleration comfort on choppy corner exits. I also noticed a little more connectivity to the the rear wheel (when hard on the gas) on flat corners with the XACT Pro shock compared to the stock shock. The XACT Pro shock is firmer so there is less wallow in the rear end when accelerating, so the rear of the KTM 450 SX-F tracks straighter and doesn’t upset the KTM’s chassis as much at speed. “Balanced” is a great word to describe both ends of the KTM, but I did notice the harder I pushed the more it rewarded me. If I tried to ride smoother/slower, the action of the shock wasn’t quite as comfortable as the stock shock. This XACT Pro likes to be pushed and will reward the rider that is aggressive because of its much more consistent nature (compared to the stock shock). Again, going to a WP authorized dealer and having it set up for you is key. Thinking that you’re just going to go purchase A-Kit level suspension, slap it on, and then magically be in heaven on the track is completely foolish! Get it set up for your weight, riding ability, and the type of rider you are will ensure that your money is spent correctly.
Do you “need” these WP Pro Components on your machine? If you’re a casual rider, of course not. However if you’re a KTM/Husqvarna rider and race consistently, I think the WP Pro Components are worth the price. For around $3499.00 for the fork and $2199.00 for the shock it’s an investment that you should take seriously. If it was me, had one bike, was on either a KTM or Husqvarna, I would invest in a set of WP Pro Components because when I ride/race, I want the most consistent feel I can get. I also know that if you are the type of rider that gets a new KTM/Husqvarna every couple years, you’re able to roll these WP Pro Components over to your new bike. This is an investment that you can continue to roll over with each passing model year. I think it’s safe to say that KTM or Husqvarna will not change their motocross models until the year 2022, so your WP Pro Components will fit at least until then. Even if KTM/Husqvarna change their machines drastically, chances are these newer WP Pro Components will bolt on.
“Keefer, have you tried a set of standard re-valved WP AER forks and shock”? The answer is yes and although the comfort was improved (over the standard/stock set of suspension), the consistency just wasn’t as good as the WP Pro Components. I would say that a set of stock re-valved stuff will definitely be good for your local racer that simply can’t afford new Pro Components. Companies like Race Tech, Kreft, and Enzo all have very good re-valved stock suspension settings.
“Keefer, is there something I can do about the rigidity I am gaining with the WP XACT Pro Component fork”? Yes, going to a WP/KTM Factory Triple Clamp will help with some of the rigidity that the stock clamps come with. Also, you can go to a bottom triple clamp torque spec of 9N/m. Both will help with comfort on braking bumps, slap downs, as well as get you less rigidity feel through your handlebars.
If you have any questions about this test, feel free to email me at firstname.lastname@example.org