Keeping your forks running smooth is not only good for your riding but also for your forks. over time dirt works its way past the dust seals and into the lower leg chambers. Not only does this impair the performance of the fork it also risks damaging the insides.
Lower leg service is pretty much the same across all Rockshox forks, and is fairly straight forward not requiring much in the way of tools or specialist equipment. This guide is written from a pike fork and only covers the lower legs, the principles are the same across all Rockshox forks.
There are two services for the lowers legs one just refreshes the oil and clean the foam rings, this is supposed to be done every 50 hours. The other done at 200 hours replaces all the seals as well. For me I brought a big bag of foam rings and crush washers so change them every time anyway. You can if you want to just clean the foam rings and reuse.
The 50 hours service is pretty much a strip and clean so doesn't take that much time to complete. The longest job is cleaning the lower legs, which should be done with a quality degreaser and plenty of hot water. Getting them dry after washing is imperative, it is useful to have a cloth on a stick, I use old socks on a piece of plastic pipe to clean out the insides of the legs. I'll generally strip my fork clean it and then have a coffee or lunch whilst letting it dry.
- Remove fork from frame and give a good clean.
- Depressurise the air side
- Remove the Rebound adjuster, the Pike use a 2mm hex key the Reba just pulls out
- With a 5mm hex key unscrew the lower bolts, not all the way leave a couple of threads in
- With a soft faced hammer gently tap the lower bolts until they are free
- Drain the fluid out of the lower legs
- Remove the uppers from the lowers
- Drain the final fluid out
- Clean the uppers to remove any fluid and dirt, using Isopropanol and a lint free cloth
- Remove the foam rings
- Remove the lower crush washers
- Clean the lowers with degreaser, and warm water, thoroughly rinse and dry
- Soak the new foam rings in suspension fluid
- Install the foam rings
- Install new crush washers
- Liberally coat the dust seals with SRAM butter
- Slide the uppers into the lowers
- Add in Rockshox fork oil
- Bolt in the lower bolts
- Replace the rebound adjuster
- Pressurize the forks to your pressure settings
- Refit to the frame
It is very beneficial to record your shock pressure and rebound settings prior to starting so that you can set up your shock to where it was before you started.