How often depends on how much you ride and the conditions you ride in, but we recommend having a basic service performed at least once per year, if not every 6 to 8 months. Most manufacturers recommend having your fork and shock serviced after anywhere from 30 to 100 hours of riding, but a good rule of thumb is having it done after about 50 hours of riding.
If you ride in extreme conditions (wet, muddy, downhill racing, winter weather, etc.), service intervals should be more frequent. If your bike has been unused for an extended period of time, you may want to bring it in for a basic service as seals can dry while the bike is sitting. And, new suspension components can also feel and ride better when a basic service is done after the first few rides.
A basic fork service consists of removing the lower legs and replacing wiper seals and foam rings, cleaning and regreasing the air spring, inspecting the damper, and draining and refilling the damper if necessary (for open bath dampers). For a basic shock service, we rebuild the air sleeve with new seals and replace the oil that is in the air spring (yes, there is a small amount of oil in the air spring).
We highly recommend that you have a full suspension service done every other year. For forks and shocks this includes everything performed in a basic service plus a complete rebuild of the damper and air spring with new seals.
We do not recommend attempting to prolong service intervals by lubing stanchions or seals. Contaminants can be introduced into the system, and after 6 months or so, fluids typically need to be replaced anyway so it's worth having a basic service performed. Wiping down your stanchions after you ride, however, is a good idea, and you should consider checking your suspension's sag every month or so (more on this topic in the next Did you know....stay tuned!).
To learn more about suspension service, check out the following links and always feel free to talk with one of our techs the next time you're in the shop!