MXA TEAM TESTED: WP XACT PRO 6500 DROP-IN CARTRIDGE FORK KIT

WHAT IS IT? The Xact Pro 6500 cartridge kit allows you to convert your WP Xact air fork into a closed-cartridge coil spring fork.

WHAT’S IT COST? $1300 (cartridge kit). 

CONTACT? www.wp-suspension.com or your local dealer. 

WHAT STANDS OUT? Here’s a list of things that stand out with the 6500 coil-spring conversion kit.

(1) Design. The WP Xact Pro 6500 cartridge kit modifies your standard WP forks to create more precise cornering and consistent feedback from the track, thanks to closed-cartridge technology. The pressurized damping unit prevents loss of damping during rapid, repetitive movements.

(2) Fork. The MXA wrecking crew is always looking for better fork settings on our Austrian-built test bikes, which includes KTM, GasGas and Husqvarna off-road models. We want better hold-up at high speeds and in big G-outs without giving up comfort in rocky singletrack and small, square-edged chop. 

On our initial test of the WP Xact Pro 6500 cartridge kit, we went with 5.0 N/mm fork springs and softer valving. The initial feel of the fork was unbelievably comfortable and improved front-end traction immensely. Our Vet test riders loved this feel, but when we switched to expert/pro-level test riders, they didn’t think the forks would ramp back up enough in the middle and bottom portions of the stroke in big hits. To fix this, we added 30cc of fork oil and removed shims from the cartridge’s base valve.

(3) AER vs. 6500. As a rule, the MXA test riders like WP’s AER air fork for several reasons. First, it allows us to adjust the comfort level based on the test riders and the ever-changing terrain they ride on. Second, the AER air forks are 3 pounds lighter than any coil-spring fork. Test riders immediately commented on the heavy feel of the coil-spring forks. 

The biggest issue with the stock WP air fork is that the pressure ramps up deep in the stroke—not something you want when chasing comfort. The WP Pro 6500 cartridge kit allows you to modify your stock forks with drop-in springs that provide a consistent feel in corners and over bumps. The best part is that you don’t have to check your fork’s air pressure (other than to bleed excess air out of the bleed screws). 

(4) Performance. After 20 hours, countless motos and hours on the trails, we found that with the Pro 6500 kit we could race motocross or cross-country with just a few clicks in either direction. Best of all, the forks were plush in braking bumps and allowed the front wheel to remain in contact with the ground. 

We set the compression at 12 clicks out (8 out for pros and 20 out for enduro riding). The rebound worked best at 16 clicks out. Thanks to adjustable preload on the fork springs, we could set the preload to 0 for vets or a half-turn in for pros.  

WHAT’S THE SQUAWK? How could we complain about added comfort, improved front-wheel traction and no need to check the air pressure?

MXA RATING: The WP Pro 6500 cartridge spring kit is something you can easily maintain and install after work in your own garage. We like that. We found it difficult to find anything to complain about (apart from the added weight and corresponding heavy feel).