How often should you change your suspension fluid?
I've had a lot of people lately ask me, how often should my shock oil be changed? First of all, every riders shocks will be different depending on a lot of factors: How often do you ride, How restrictive is your valving, and How hard do you ride. My advice is to have your shocks serviced at least once every season and at least twice a season if you race every weekend. It's hard to put an exact time frame on them because of the many factors I listed above. I don't exactly know how much it affects the breakdown of your suspension fluid, but depending on your suspension settings, if you have your settings more on the harder settings then the orifices that the oil travels through are smaller which will break it down faster. You would be surprised how much difference your oil being changed makes on the valving characteristics, even if the oil still looks good in the shocks. The oil in shocks break down the same as oil in your cars engine and breaks down the same way loosing its viscosity. Another problem is that the shocks get air in them where the oil is which acts just like a worn out steering stabilizer. There will be a lot of movement in the shocks travel where there is no restriction of oil movement because it is air moving through the valving stack rather than fluid. In this case, you need to replace your seal head seals, which are fairly inexpensive and I highly recommend replacing them at least once per year too!
Here is a basic recommended schedule:
Pro Racer - Every Race (Replace seals every other time)
National Amateur Racer - 4 times per season (Replace Seals at beginning of season and half way through)
Local Amateur Racer - 2-3 times per year (Replace Seals at beginning of season and half way through)
Trail Rider - 1 time a year (Replace Seals once a year)