HFS PRO kit has an air cartridge and a spring in each stanchion. Both work in serial (spring below air cartridge).

Cartridge pressure is adjusted with a manual air pump with a pressure gauge. Pressure etup process is described in the installation manual, and it is made basically depending on rider´s weight and riding preferences.

HFS PRO is completely progressive, and it is designed to absorb quite smoothly at first part of fork travel, getting harder progressively with very good bottoming resistance.

HFS EXPERT has an air cardridge and a spring in the right stanchion, and a combination of two springs and a special spacer in the left stanchion.

In left stanchion, upper nut has a threaded screw that allow setting up the mechanical pre-load. The intermediate spacer defines the point where the stiffer stage starts, and it can be changed just by inputting it in one way or another. 

Same as in HFS PRO, cartridge pressure is setup with a manual air pump.

HFS EXPERT is progressive and it has a sift behavior at the beginning, and it is getting stiffer with the fork travel, helping to avoid suspension bottoming at the end of travel.

HFS EXPERT mk2 has a set of 3 springs and 2 spacers in each stanchion. Response is progressive through three linear stages, getting a curve very similar to the continuously progressive one. With Expert mk2 it is not necessary a pressurization pump.

Upper nut ias a threaded screw with possibility to setup the mechanical preload. It is possible to install additional or different spacers so that suspension response is very easily adjusted. This is very interesting because the system can be fine tuned according to rider´s weight, or riding preferences. 

HFE EXPERT mk2 is “3 stage progressive”, and response is soft at the beginning, getting stiffer with the fork travel, and helps very well to control bottoming resistance.

HFS CLUBMAN has in both stanchions a set of 2 springs and 1 spacer. Upper nut has a threaded screw that allow setting up the mechanical preload.

CLUBMAN kit does not have an air cartridge. approximately first half of fork travel has a soft response, and second half is stiffer. The point of change is easily adjustable just by inserting the spacer in one way or another.

HFS CLUBMAN is only available for Trial Classics.