The Facts About Suspension Service

Let’s be honest: suspension is one of the best things ever bolted to a mountain bike. Not only does it soften the harshness of terrain, but it increases traction and stability, keeping the bike glued to the ground where a hardtail can be bucked around. It also decreases fatigue over long rides and generally makes your bike feel like a magic carpet, capable of anything Mother Nature can throw at it. Best of all, suspension has never been as good as it is right now, providing adjustability for a wide range of riders in a relatively lightweight and affordable package.

However, in order to maintain all these benefits, suspension requires regular servicing. We’d like to help riders understand what these services are and when to have them done.

Many riders never actually service their suspension at all. This is a shame; it’s like buying a Ferrari and never changing the oil. Eventually, your nice bike rides poorly, and the money you initially invested into suspension is no longer returning its benefits. And the degradation has happened so slowly you probably haven’t noticed it, so you shrug and decide you don’t need to do anything, anyway. But every time you ride your bike, suspension oils continue to break down, seals continue to wear out, and the potential for a mid-ride problem starts to increase.

A typical issue is a blown fork seal, which will send oil flowing down the outside of your fork leg(s). If it’s the non-drive side seal, that oil will usually contaminate your front brake, which is dangerous since you’ll experience an almost total loss of power in that brake. It will cost you new brake pads, possibly a new rotor, and the labor required to get things back to normal. Meanwhile, your fork is now running dry of oil, over time wearing out the expensive coating on your stanchions. Letting this situation continue will eventually cost you anywhere from a couple hundred dollars in parts and labor to possibly $1000 for a new fork. Meanwhile, you could have prevented all of this with a simple lower leg service for $65.

Similarly, you might also suffer breakdown of the shock’s air can seal. This will cause all the air to leave your shock in the middle of a ride, which will force you to walk whatever miles remain. Another issue would be damper malfunction, making the shock feel harsh and bouncy as damping functions are lost. Racers in particular should pay close attention to suspension maintenance, since no one wants this to happen in the middle of a race they paid hard-earned money to enter.

Every manufacturer recommends certain services after a specific number of hours. That fork lower leg service, for example, might be recommended after 50 hours. Many riders are probably thinking, “Wait a minute… if I ride a lot, I would need to do that service every couple of months! I can’t afford that.” The key thing to understand is that this number refers to actual time that the suspension is being cycled. So each rider should take a look at what kind of riding they do. If you live in Colorado or California and do lots of dirt road riding to access singletrack, there’s very little cycle time occurring during those climbs. You could estimate how much time out of a typical ride is spent descending, and base your service interval on that number. Alternatively, if you live or ride regularly in Moab or a similar place where the entirety of your riding includes aggressive cycling of the fork, you truly do need to have that service more frequently. Bottom line, the most simple approach is to have the fork and shock completely serviced at least once a season (more often if you ride year-round), while keeping a close eye on those fork seals for any sign of oil. If you ride often in mud or sand, or you aren’t very diligent about keeping your suspension clean, plan to do more frequent maintenance.

Fork lower leg service: The seals, which play a vital role in keeping oil in and dirt out, get replaced. The oil that lubricates the bushings is changed and all surfaces are cleaned, removing broken-down oil as well as particulates that could damage the nice, slippery surface of your stanchions.

Air spring service; damper service: these services maintain the effectiveness of the parts that make suspension feel so good: the spring itself and the damper that controls its movement. Depending on the damper you have, that will include removal of old oil and particulates, and some forks require bleeding a bladder-based system.

Shock air can service and damper service: Same concepts as fork service, but also includes replacing the many o-rings that create air- and oil-tight seals within the shock. Some services may also involve recharging the nitrogen chamber that helps to control the damper.

Barring the issues mentioned above —which need immediate attention — your regular maintenance is best done in the off-season. Not only is that a time where you are more willing to be without your bike for a few days, but shops are much less busy. While everyone else waits until spring and is in a panic to get their bike back for the next weekend in Fruita, you got your service out of the way in January and are ready to go.

Another tip: If you have an unusual or proprietary piece of suspension, allow a bit of extra time in case parts need to be ordered.

Over time, your bicycle’s linkage will also show signs of wear. Whether your bike uses bearings or bushings in the pivots, those will eventually break down, giving the rear end a rough, sticky sensation that can spoil the wonderful feeling of a freshly serviced shock. Your mechanic can check the linkage once the shock has been removed, and that’s the perfect time to service it. Your bike will feel like new again!