WP 4CS Fork Tech Specs

• Inner fork tube OD: 48mm
• Damper rod OD: 8mm
• Pressure spring: 1.8-2.3kg/mm
• Oil height range: 60-140mm
• Oil weight: 4wt
• Compression adjuster: 25 clicks
• Rebound adjuster: 25 clicks
• Base valve specs: 6x28x13   (IDxODxH)
• Mid valve specs: 6x20x13     (IDxODxH)

Ride JBI's Review of the WP 4CS Fork
The WP 4CS fork is made from quality parts with a nice finish.  The design shares similarities with open cartridge forks, closed cartridge forks, and the Ohlins TTX.  In other words it is a mix mash of ideas assembled into one.  Since the inception of the WP 4CS fork there has been many revisions of the production units.  The early WP 4CS forks featured an innovative hydro stop that provided positive bottoming control and feel.  Over time WP began to eliminate the function of hydro stop before removing it all together.  Removal of the hydro stop feature requires the forks to rely purely on the "air spring / oil level" for adequate bottoming control.  The downside is forks with high oil levels (aka very progressive air springs) get too stiff too quickly in bumpy situations such as multiple stutter bumps, rocks, or sharp edge bumps where the forks need to compress quickly and fully.  This is 1 of the major drawbacks of the 4CS fork, as all over production forks (KYB SSS, Showa Twin Chamber, Showa TAC, WP CC, WP Cone Valve, and WP AER) utilize at least 2 or 3 different types of bottoming controls such as hydro stops, spring seats, and massively high air pressures that come with air forks.  A fork with adequate bottoming controls allows the the rest of the fork to be setup smooth and plush for maximum feel.  The MXT 4CS Huck Valve is the best solution for improving the bottoming control of the WP 4CS fork and also being able to decrease oil level for improved feel.  Next the 4CS fork is unique in that there is only 1 compression adjuster and 1 rebound adjuster.  Because of this design the tuning window for this fork is small limiting the range of terrain it can handle well.  The MXT 4CS Clickers are one solution that puts 2 compression clickers at the bottom of the fork and converts both top clickers to rebound.  The addition of the MXT 4CS clickers improve the overall tune-ability of the fork but also improve initial feel as the MXT 4CS clicker features an internal subvalve.  The idea and design of the 4CS fork is not actually bad, however the stock setup is very poor in terms of valving and function.  For best results this fork requires hardware upgrades to be competitive with other stock forks. 

JBI Suspension Valving Mods Available