How To: Servicing Fox 49 with Grip 2 Damper

Maintaining your suspension fork will have your bike performing at its best! If you are starting to feel like your Fox fork isn't riding buttery smooth like when it was new, chances are its time for a lower leg service. Fox recommends a lower leg service about every 50 hours of riding, and it's a relatively quick and easy way to freshen up your fork. In this MTB How To, we are going to be doing a lower leg suspension service on a Fox 49 fork with the Grip 2 Damper. In this service, we will pull the lowers off of the upper tubes, replace the foam rings, and add new bath oil. Before we get started, make sure your fork is nice and clean, that way we don't introduce any dirt or contaminants into the system.  

Servicing most Fox forks follows a very similar process, so if you are looking to do a lower leg service on your Fox 36 for example, there is still some great info in here for you as well. If you are servicing a Fox 40 with a 27.5 chassis, follow the same exact process here. Let's get in to it.

How To: Servicing Fox 49 Fork - Worldwide Cyclery

What Tools Do We Need?

  • We need to make sure we have all the right tools for the job. For starters, you will need a Fox 40 Dust Wiper kit. We offer a variety of Fox dust wiper refresh kits either from Fox, Push Industries, or SKF. The dust wiper kit will include most importantly new foam rings, crush washers, and dust seals. 
  • For the FIT Grip 2 damper, you will need Fox 20wt Gold oil for the air spring side of the lowers and Fox 5wt Teflon infused oil for the damper side. This oil is just bath oil for the lower assembly since the Grip 2 damper is a sealed cartridge.
  • We will need some kind of oil drain pan, two small plastic cups to soak your foam rings, and a syringe to add oil to your fork. 
  • For tools, we will need a 2mm hex key, a standard socket wrench, a deep 15mm socket, a 10mm socket, a rubber mallet, a torque wrench, a pick, and a Fox Digital Shock Pump.
  • It will also be handy to have some Maxima Suspension Clean and a few clean rags to clean the fork both before and after the service. 

Servicing Fox 49 Fork - Worldwide Cyclery

1. Record All Damper Settings

  • It's possible to do this service without changing any damper settings but it would be smart to jot down all of your damper settings just in case. Turn each adjuster clockwise and count each click until closed. Write down the particular setting and then turn the adjuster back out counter clockwise the same amount of clicks. For tuning purposes as well, it's handy to have your damper settings written down somewhere. 

2. Release Fork Air Pressure

  • Just to be safe, it's always a good habit to remove all of the air pressure before working on your fork. Use the 2mm hex key to remove all of the air inside the air spring. 

Servicing Fox 49 Fork - Worldwide Cyclery

3. Remove Rebound Knob

  • First unscrew the rebound knob cap and set it to the side. Using a 2mm hex key, loosen the pinch bolt on the low speed rebound knob. You don't have to unscrew the pinch bolt all the way, loosen it and both the low speed and high speed rebound knobs will slide off. 

Servicing Fox 49 Fork - Worldwide Cyclery

Servicing Fox 49 Fork - Worldwide Cyclery

4. Remove Bottom Nuts

  • Before you try to remove either of the two bottom nuts, clamp the fork in the stand so that the bottom of the fork is higher than the top.
  • Using a 15mm deep socket, remove the damper side bottom nut and crush washer. Keep the bottom nut close by, you will need it in just a minute. You might need to use a small pick to remove the plastic crush washer. 
  • Using a 10mm socket, remove the air side bottom nut and crush washer. Keep the bottom nut close by, you will need it in the next step. 

Servicing Fox 49 Fork - Worldwide Cyclery

Servicing Fox 49 Fork - Worldwide Cyclery

5. Knock Free Lower Legs

  • We will be using the bottom nuts to help knock the damper rod free from the fork lowers. All we are doing here is compressing the damper rod and air spring rod to detach them from the bottom of the lowers. This will allow us to remove the lowers in the next step. 
  • Thread both bottom nuts half way on to the damper rod and the air spring rod. On the damper side, place your 15mm deep socket on to the bottom nut and tap the socket with the rubber mallet until the damper rod separates from the bottom of the lowers.
  • On the air spring side, place the 10mm socket on the bottom nut and tap the socket with a rubber mallet until the air spring rod separates from the bottom of the lowers. 

Servicing Fox 49 Fork - Worldwide Cyclery

Servicing Fox 49 Fork - Worldwide Cyclery

6. Remove Lower Legs And Drain Oil

  • Now that both the damper and the air spring rods are separated from the lowers, point the bottom of the fork down in to your oil drain pan. You can now pull each off the upper tubes out from the lower legs one at a time. Set both upper tubes off to the side where they won't get scratched or damaged.
  • Leave the lower legs upright in the oil pan until all of the old bath oil has drained out.

Servicing Fox 49 Fork - Worldwide Cyclery

7. Remove Old Foam Rings

  • Using your pick, carefully remove the old foam rings sitting underneath the dust wipers. The foam rings are soaked in bath oil and are there to catch and collect dust, dirt, and grime that finds its way inside the fork. Remove the old foam rings and throw them in the trash. 

Servicing Fox 49 Fork - Worldwide Cyclery

8. Inspect Dust Wipers 

  • This is the perfect time to inspect your dust wipers. Nine out of ten times the dust wipers are in perfect shape and can be reused. For the fork here, the dust wipers look brand new so there ins't any need to change them.  Make sure the durst wipers are clean before moving on. 
  • If you do need to change your dust wipers because they are either torn or cracked, to remove them, use an open end wrench and gently pry them up out of the fork lowers just like in the photo below.
  • To install new dust wipers, lightly lubricate the outside of the seal and set one of the dust wipers in to place. One trick for pressing them in is to take the old dust wiper and place it on top of the new one. You can press with your hand or lightly tap the old seal stacked on top until the new dust wiper is firmly in place.

Servicing Fox 49 Fork - Worldwide Cyclery

Servicing Fox 49 Fork - Worldwide Cyclery

9. Clean Lower Legs and Upper Tubes

  • Use some Maxima Suspension Clean to wipe down both the lower legs and upper tubes. Before we start reassembling the fork, make sure everything is nice and clean!

10. Install New Foam Rings

  • Because each side of the fork uses different bath oil, place a small amount of Fox 20wt Gold into one cup and a small amount of the Fox 5wt Teflon infused oil in another. We want to soak the foam rings in bath oil before we install them, and so place one foam ring in the 20wt Gold oil and one foam ring in the 5wt Teflon oil. 
  • After both foam rings have been soaked completely in oil, place the foam ring with 20wt Gold oil in to the air spring side of the lower legs. From a riding perspective, that would be the left side of the fork. Place the foam ring soaked in 5wt Teflon infused oil in to the damper side of the lower legs. 

Servicing Fox 49 Fork - Worldwide Cyclery

Servicing Fox 49 Fork - Worldwide Cyclery

Servicing Fox 49 Fork - Worldwide Cyclery

11. Install Air Spring Upper Tube

  • Before sliding the air spring upper tube back in to place, pump up the air chamber to anywhere around 40 psi. This will allow the air spring rod to fully extend and will make it easier to reassemble the fork.
  • Slide the air spring upper tube in to the lowers until just before the air spring rod comes out the bottom of the lowers. This will allow us to add oil in the next step. Be careful not to pinch the foam ring when sliding in the upper tube. 

Servicing Fox 49 Fork - Worldwide Cyclery

Servicing Fox 49 Fork - Worldwide Cyclery

12. Add Fox 20wt Gold Oil To Air Spring Side

  • Before adding oil, clamp the air spring upper tube in the stand so that the bottom of the fork is higher than the top. This way when we add bath oil, the oil will stay inside the lower leg assembly.
  • Using the syringe, add 35cc of Fox 20wt Gold suspension oil in from the bottom of the lowers. If you are working on a different fork, find the Fox oil bath chart at the bottom of the page so you know how much oil to add to your fork.
Servicing Fox 49 Fork - Worldwide Cyclery

    13. Install Air Spring Bottom Nut

    • Not that the air spring side of the lowers has bath oil, slide the lowers fully on to the upper tube so that the air spring rod is poking out the bottom of the lowers. 
    • Install the smaller of the two crush washers, thread on the bottom nut, and torque the bottom nut to 5.7Nm (50in-lbs).

    Servicing Fox 49 Fork - Worldwide Cyclery

    Servicing Fox 49 Fork - Worldwide Cyclery

    14. Install Damper Upper Tube

    • Now we will repeat a similar process for the damper side. Slide the damper side upper tube in to the lowers until just before the damper rod comes out the bottom of the lowers. This will allow us to add oil in the next step. Be careful not to pinch the foam ring when you slide in the upper tube.

    Servicing Fox 49 Fork - Worldwide Cyclery

    15. Add Fox 5wt Teflon Infused Oil to Damper Side

    • Using the syringe, add 50cc of the Fox 5wt Teflon Infused oil in to the damper side of the lower leg assembly. If you are working on a different fork, find the Fox oil bath chart at the bottom of the page. 

    Servicing Fox 49 Fork - Worldwide Cyclery

    16. Install Damper Bottom Nut

    • Now that the damper side of the lowers has bath oil, slide the lowers fully on to the upper tube so that the damper rod is poking out the bottom of the lowers. 
    • Install the larger of the two crush washers, thread on the bottom nut, and torque the bottom nut to 5.7Nm (50in-lbs).

    Servicing Fox 49 Fork - Worldwide Cyclery

    Servicing Fox 49 Fork - Worldwide Cyclery

    17. Reinstall the Rebound Knob and Cap

    • Slide both the high speed and low speed rebound knobs on to the end of the damper rod. Use the 2mm hex key to lock the low speed rebound knob in to place. Screw on the rebound cap and you are all good to go. 

    Servicing Fox 49 Fork - Worldwide Cyclery

    Servicing Fox 49 Fork - Worldwide Cyclery

    18. Clean the Fork and Reinstall it on to Your Bike

    • Use the Maxima Contact Cleaner or any other kind of degreaser again to wipe off any excess oil on the outside of the fork. Reinstall the fork back in to the crowns on the bike and be sure to set your fork pressure again before your next ride. Cycle the fork up and down a few times to equalize the positive and negative air chambers while you are setting your exact fork pressure. 

    Servicing Fox 49 Fork - Worldwide Cyclery

    If you are working with a Fox 36, check out our How To: Servicing Fox 36 Fork with HSC/LSC Damper.

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    2019 Fox Oil Bath Volume Chart

    2019 Fox Oil Bath Volume Chart - Worldwide Cyclery


    May 02, 2019

    Fork › Fox › How To › Suspension ›

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