How to service your MTB fork?

Too many riders unfortunately neglect this point — the fork is an important part of your bike's chassis and is constantly under stress when you ride.

• Time: 3h30
• Level: Very difficult
• Tools: Allen key set | Tyre lever | Clean cloth | Wiper seal installation tool | Socket wrench | Measuring cup | Fork oil | Fork/seal grease | External seal kit (or wiper)

Data may vary from one manufacturer to another, but you can keep these intervals in mind:

• Before every ride: check the cleanliness, condition and lubrication of your stanchions
• Every 40 hours (~20 rides): drain the hydraulic cartridge oil, replace the wiper seals
• Every 100 hours (~50 rides): drain and replace the complete seal kit

The 100-hour service being quite a major operation, we recommend having it carried out by a specialist, but here is how to perform the 40-hour service yourself.

Warning: this procedure is only valid for cartridges with an "open bath*"For forks, so-called open hydraulic cartridges are simpler in design and therefore easier to maintain.. For "closed* cartridges"For forks, so-called closed hydraulic cartridges are designed to isolate the oil from the air, in order to prevent emulsification among other things, and thus ensure reliable hydraulic behaviour. (FIT*High-end sealed cartridge system offering three instant positions for compression damping (open, medium and firm) in order to adapt to different terrains or Open Cartridge*Simple hydraulic cartridge, easy to adjust and maintain, offering smooth and reliable operation. from Fox, Charger Damper*Charger Damper with high-efficiency circuits (Pedal and Lock mode) guaranteeing optimal downhill performance while maintaining the pedalling stability essential on steep climbs, and offering greater sensitivity to small bumps. from Rockshox, etc...) the operation being considerably more complex, it is recommended to have it carried out by a specialist.

Steps

Warning: depending on the fork model, a few steps may vary — it is advisable to consult the manufacturer's manual, which you can often find on the brand's website.

1. For an air fork, fully deflate the air chamber; in the case of a coil spring fork, remove the cap at the top of the spring-side stanchion to take it out.
   
   
2. Remove the adjustment knobs and screws at the bottom of the lowers. Leave them engaged by a few turns then tap them with a mallet to "release" the cartridges from the lowers. Then remove the screws. Note that a small amount of oil will come out through these openings.
   
   
3. Separate the stanchions from the lowers by pulling firmly on them.
   
   
4. Using a tyre lever, remove the wiper seals and foam rings from the lowers.
   
   
5. Clean the inside of the lowers and the seal housings with a clean cloth.
   
   
6. Install the new foam rings pre-soaked in fork oil, then refit the new greased wiper seals using the installation tool and a mallet if necessary.
   
   
7. On the stanchion side now, remove the adjustment knobs and caps then drain the oil into a measuring cup to check the amount of oil required for reassembly. Operate the piston 1 or 2 times to fully drain all the oil.
   Probikeshop Tip: perform this operation one stanchion at a time.
   
   
8. Fill the stanchions with the new oil. For viscosity and quantity, refer to the manufacturer's specifications and check against the amount of oil you removed.
   
   
9. Refit the top caps then the adjustment knobs.
   
   
10. Clean the stanchions with a clean cloth then grease the wiper seals generously.
    
    
11. Reassemble the stanchion section into the lowers, making sure the wiper seals slide smoothly along the stanchions.
    
    
12. Before fully assembling the two parts, insert the suspension fluid through the lower openings of the lowers then push the stanchions all the way in.
    
    
13. Refit the screws and knobs at the bottom of the lowers.
    
    
14. For an air fork, set the pressure appropriate to your weight. In the case of a coil spring fork, refit the spring.
    Probikeshop Tip: operate the fork a few times by hand to check that everything works without issue.

Your fork service is now complete. Remember to lubricate the stanchions regularly to maintain full sensitivity in operation and preserve your equipment.