Suspension has had a place in mountain biking since the early 1990s, and it’s played a pivotal role in how we ride. The demand for the perfect set up keeps shock manufacturers exploring how to handle everything from washboard ripples to the landing of a triple backflip off a canyon wall. Often though, riders just “feel or know something works” without really understanding how or how it could work better. We spoke with Holly Colson, Cane Creek's director of marketing, Joel Smith, X-Fusion’s general manager, and Doug “DD” Dalton, RockShox technical ambassador, to give their professional advice about getting the best bounce on the bike.
Suspension technology, especially in the realm of full suspension, has progressed rapidly in the last few years and led to bikes that work so well that traditional hardtails are starting to become a niche segment of the market. With that increased popularity, though, comes more choice, more lingo, and more claims. Being able to talk about what suspension feels like when set up properly will make selecting the right rig easier, improve user experience, and getting more people riding more frequently. So starting with the basics...
Give us your simplest definition of suspension preload, compression, and rebound to a novice user.
Colson: Preload affects the energy in the spring. Adding preload increases the ride height of the bike, decreasing sag. Reducing preload does the opposite: It lowers the ride height of the bike and increases sag. If too much preload (more than six turns on our coil rear shock) or too little (less than one turn) is required, the rider may not have the correct spring rate on their shock. Riders can refer to our online spring rate calculator to confirm.
Damping is in place to resist movement. One nice rule to remember is that compression damping tries to keep the wheel on the ground, while rebound damping tries to keep the wheel off the ground. Therefore, compression allows for controlled upward movement of the tire to absorb the bump while rebound sends the tire back down for contact with the ground in a controlled fashion.
Smith: Rebound is the return of the fork after compression to static ride height. Compression is the downward movement of the suspension. Preload is the amount a coil spring is compressed at its static state.
Dalton: Compression is interrupting laminar flow to create hysteresis...just kidding! As the fork goes down and the wheel comes up, hydraulic resistance is created. Rebound slows the wheel as it returns back to the ground.
What’s the best process you’ve seen for quickly and effectively setting up suspension for a demo or test ride?
Colson: Properly setting sag—the difference between the suspension when it is fully extended (not compressed) and when the bike is on flat ground under rider weight including riding gear—is of course priority one. Then to meet the needs of a demo, have a quick Q&A about what the rider likes or is looking for in his setup, and make a few clicks and turns to suit that feedback. To really dial in the ultimate ride, a rider can and should follow the steps we provide on the Cane Creek website with our online Tuning Field Guide.
Smith: Check suspension sag, and then adjust rebound speed. Adjust compression damping on the trail to taste.
Dalton: Setup is the most important; follow the air chart on the back of our fork legs. With RockShox’s Solo Air, one fill gets positive and negative air springs set. Next, set rebound as fast as possible with resistance. Outside of preload, what changes should you make when tuning suspension for lighter weight or heavier riders?
Colson: When you get to extreme ends of the weight scale you always need to adjust compression settings.
Dalton: Make the rebound match the spring rate.
Would you set up suspension differently for a novice rider compared to a seasoned rider?
Colson: Absolutely! More experienced riders will generally be moving faster and hitting things harder, and they appreciate firmer compression settings. Faster rebound (less rebound damping) benefits experienced riders also, as they will know how to use the “pop” to his or her advantage without being bucked or thrown.
Smith: Yes. More experienced riders tend to run higher spring rates and higher compressing damping settings.
Dalton: Only spring rate and rebound. Novice riders ride more slowly, so less force is seen. Force equals mass times acceleration, so less force needs less spring, and less spring needs less rebound. Then adjust compression accordingly.
Out Of The Parking Lot
What adjustments do you change every time when riding a new trail?
Colson: Assuming you've never seen what is coming and have no idea what to expect, it would be difficult to know what to adjust for. Best to be confident in your suspension. However, low-speed compression adjustments are most commonly changed to suit varying trail situations such as long uphills and long downhills.
Are there suspension adjustments that riders fiddle with too often? What suspension adjustments do riders not change often enough?
Colson: Riders change HSC (high-speed compression) too often; some tend to attribute every perceived issue as a problem with compression, and it seems to be the one setting people are less scared to turn.
LSR (low-speed rebound) adjustments are left alone too often. LSR works in concert with LSC to stabilize the chassis and manage traction. It is analogous to the single rebound adjuster on most other rear shocks. Rider-tuned LSR adjustment (combined with LSC, or low-speed compression) ensures maximum traction during technical climbs, high-speed chatter, off-camber corners and braking in stutter bumps. One beauty of the Climb Switch on our Double Barrel shocks is that rebound can be run faster (less damping) in “open” mode than is allowed by other shocks. This is because a shock properly damped in rebound for “fast riding” will feel too bouncy and annoying when climbing with your weight back and on saddle. If you only have one setting, you’re compromising between performance when you’re seated and when you’re standing
Smith: Riders don't check sag often enough. There is pressure loss in any air system over time, and accurate sag makes the biggest impact on ride performance. I don't think you can fiddle with your suspension too much.
Have any tips for the best way a shop can effectively plant the seed in customers' minds to bring their suspension back in for regular service?
Colson: Physically demonstrate how tweaked the rider’s shock or fork is from neglect. Some riders don't notice when their suspension performance is beginning to degrade. Actually feeling a properly serviced shock brings that good-times memory right back.
Smith: Tell them their suspension is like a car, and like a car, requires regular service.
Dalton: Starting in 2013 RockShox ships a service kit with all its aftermarket forks. This starts the conversation at retail that suspension requires service.
What type of rider is the perfect candidate for upgrading a new bike’s fork or rear shock?
Colson: One that just got paid—Ha! Everyone can benefit from a suspension upgrade, especially if they desire to have a smoother ride, the ability to pick the best lines with more confidence, and improve their overall riding ability.
Smith: One that has not performed service on his or her suspension in more than two years.
Dalton: Anyone that didn't get RockShox as OE equipment.