Understanding Suspension

Understanding Suspension Rocks and roots, cracks and curbs — this is the terrain with which bikes must contend. Bikes are tough and can take most of the abuse any terrain can dish out. But your body is more susceptible. At the end of a ride, each bump and dip can become an aching back, sore knees or strained wrists. Enter suspension. The idea is pretty basic — isolate you, the rider, from the abuse delivered by everyday riding. In recent years, technological advances have made suspension light and reliable. Good suspension makes the bike handle better and saves you from wear and tear on your body. Suspension is so good now that even low-end mountain bikes come with a suspended fork. In fact, there are some designs that are light enough even for road bikes! Is Suspension Right for You? The answer, in almost all cases, is yes. You'll find your bike corners better and has increased traction and ride characteristics. But to make sure, answer these 4 questions. 1.Do you ride primarily over rough singletrack?Yes — Rough singletrack means a lot of rocks and drops and jarring bumps. You'll want beefier suspension (perhaps even dual suspension). No — If you ride primarily over logging or fire-roads, or even if you ride on smooth, paved roads, low-end suspension can help ease some of the stress on your body, especially your back. 2.Are you interested in fast descents down mountainsides? Yes — Get full suspension. And, if you ride a chairlift up the mountain, you can get by with long-travel, heavy-duty suspension and a beefy frame. Your bike will weigh about 40 pounds, but you'll be able to scream down a mountain. No — Then see the "Yes" and "No" answers to the first question. If you are a road cyclist, obviously you won't need suspension to handle those long, winding strips of asphalt. 3.Are you 30 years old or older? Yes — The fact is, the younger you are the more you can absorb bumps. You can get by without suspension. However, most young riders choose at least front suspension because of the improved ride it delivers. Older riders benefit from even basic suspension like a combination of a suspended fork and suspension seatpost. Gel saddles are also good if your riding style is more casual. Manufacturers have now got the weight down on dual-suspension bikes and many older riders are choosing these bikes. No — Just wait. You can get by without it, but you'll wish you had used suspension in your younger years. 4.Do you ride often (1 or more times a week)?Yes — The more you use something, the more wear and tear it experiences. At least, this is true of machines. The human body, however, is remarkable in that the more it gets used the better it functions. Up to a point, that is. If you're riding over the rocks and roots more than once or twice a week, you may soon find your body going on strike and unwilling to cooperate. With suspension you can tease a few more rides a week out of your body. No — Suspension can be handy, especially if you answered "Yes" to any of questions 1 through 3 above. However, if you answered "No" to all of the questions above, you can get by without suspension. If you ride a road bike, tandem or recumbent ... You still may want to try a suspended fork for the road bike or tandem. They're making their way onto these bikes, and cyclists who ride them are finding the forks save their wrists. Recumbents are increasingly coming with a suspended rear wheel. What About Commuting? Bicycle commuters benefit most from simple suspension like a flex-stem and suspension seatpost combination. Since both offer 25mm to 50mm (1 to 2 inches) of suspension, they take out most "chatter" or vibrations from the road as well as help soak up the bumps from cracks, street-level changes and minor potholes. Suspension Types There are many types of suspension. Most are made of metal — 1 is made of flesh and bone. Fork The first viable suspension, the suspended fork, is still the mainstay of the mountain biking industry. They come in 2 types: short travel or long travel. What type you use depends on what type of riding you do. For normal singletrack, whether hardpack or loose dirt, a short-travel fork 50mm to 80mm (2 to 3 inches) works best. For downhill, where you expect to take big hits, a long-travel fork 100mm (4 inches) is the best choice. There are some forks on the market that boast anywhere from 120mm to 180mm (5 to 7 inches) of travel. Let the pros have these forks. They're heavy and made for extreme downhill where there is no intention of riding the bike back up the mountain. Flex-Stem Put a spring or some elastomers in a stem (the bar that holds your handlebar) along with a couple of pivot points and suddenly you've got a flex-stem. First seen on mountain bikes, they proved more of a hazard than help. However, they are perfect for leveling out the minor vibrations found on a typical asphalt or gravel road. They are most beneficial as a wrist-saving add-on for casual cyclists and commuters. Rear Shock Along with front suspension (suspended fork), many new bikes now come with rear suspension (commonly called a rear shock). These bikes are referred to as full-suspension bikes and work best on rocky singletrack. Here the primary consideration is whether the weight justifies the ride. If you ride over logging or fire-roads, a rear shock is just added weight without much added benefit. (It may just be 5 pounds., but on the 17th mile of your ride, that 5 pounds. may as well be 100.) You're better off going with a suspended seatpost and suspended fork combination. But if you're bombing down steep, technical trails, a rear shock can be invaluable. They provide anywhere from 50mm to 80mm (2 to 3 inches) of travel for the most common brands. They are most commonly of the spring/oil variety, but some use an air/oil combination to save weight. Keep in mind: The lighter the shock the greater the cost and maintenance requirements. Seatpost Companies have been trying this concept of suspension for a while and finally have the materials and a design that seems to work. Basically, it's a simple elastomer, air/oil or spring/oil shock inside the seatpost. It comes with about 25mm to 50mm (1 to 2 inches) of travel and is perfect for the more easy-going recreational rider. Tough, new materials make the shock viable. And, they're great for climbing because once you stand up on the pedals, the suspension is gone. The one drawback to seatpost suspension is that the saddle height changes as you go over bumps. However, most riders won't notice the change. If you mainly ride over big bumps, a full-suspension bike is often the way to go. Tires Yep. The first mountain bikes were nothing more than cruisers with big, balloon tires on them. Let the air pressure out a bit and your tire becomes a shock all it's own. Most mountain bike tires are full at 50 to 60psi, but they can be ridden down to 35psi. When you ride with the air pressure this low, more of the tread at the sides of the tire is hitting the trail, thus giving you more traction. Plus, with a little more room for the air to move around, small bumps are absorbed. Look carefully at the recommended psi for your tire and don't go below the lowest number. If you do, you're setting yourself up for a pinch flat and, potentially, a long walk home. Arms and Legs Suspension can improve the quality of a ride. No question. It can also turn you into a sloppy rider. Why finesse your way around an object if you can just blast right over it? Here's why: Sloppy riding can cause more strain on your body than the bumps themselves. Using a proper riding technique will improve your ride and save your body. Your arms and legs are nature's perfect shock absorbers. Learn how to use them! New Bike or Suspension Upgrade? Consider that along with the wheels and drivetrain, suspension is the best upgrade for your money. You'll: Improve your ride. Ride longer with less fatigue. Save your back and wrists. Discover that, in some cases, a new suspension fork can be lighter than the standard fork that came with the bike. However, a new fork can cost anywhere from $200 to $700. If you need a new frame, or if the components on your bike are old and need to be updated, your most cost-effective way of getting suspension is to buy a new bike. Most new bikes come with decent suspension as well as good componentry (V-brakes, the latest shifters, etc). See our clinic on How to Choose a Bike for more information. Note: If your bike was made before 1995, it may not be upgradeable. The reason: Older bikes were designed with a more relaxed geometry. Take that geometry with a suspended fork and the bike's handling can become difficult. Check with your local bike shop to see if your bike is a good candidate for an upgraded suspension Rubber, Air or Coil? How well do you know your way around a set of tools? Different types of shocks mean a different level of upkeep. If you like tinkering with your bike, a fluid or hydraulic shock is the one for you. If you like spending more time on the trail than in the garage, a coil system offers the lowest maintenance requirements. Here are the 3 ways shocks absorb the bumps: Elastomer — Essentially rubber plugs stacked up to absorb shock, these were the old standard. The density of the rubber dictates the amount of shock absorption. They are lubed with oil and require some regular cleaning, but are not overly hard to maintain. They tend to wear out over a year of solid use. When yours wear out, replace them with coils and ride off happy. Air/Oil — Air, oil or hydraulic fluid is forced through a series of chambers to absorb the bumps. These are temperamental shocks, requiring constant upkeep. They also don't soak up the bumps as well as the other two systems. But they are very lightweight. Many pro riders opt for these kinds of shocks because of this factor alone. Coil — Good ol' springs, but with a new twist. The first coil suspension would rebound so fast, they could make a bumpy ride worse. With the introduction of oil damping systems (a way of slowing down the coil's rebound by forcing oil through chambers), these shocks have become the industry standard. They can be a bit heavier than elastomer and air/oil shocks, but they're low maintenance, requiring very little regular cleaning. They're also the perfect upgrade from elastomer. Shock Adjustments Most of the above shocks come in styles that can be adjusted. You adjust the shock to compensate for your weight (this is called pre-loading). The shock should "bottom out" — that is, become fully compressed — about once or twice a ride. If it isn't, it means you aren't getting the full use of your shock. Some shocks can be adjusted on the fly. They're more expensive, but useful when riding varying terrain. Adjusting shocks for the perfect ride is almost an art form. Factors such as pre-load, damping, lockouts, oil weight and more can be worked to dial in something approaching nirvana on wheels. However, if you just want to get on your bike and ride, most shocks can be adjusted by an experienced REI bike mechanic and be good to ride for the next year or more. A Final Note Suspension is here to stay. The technology is getting better all the time, and soon most mountain and town and country bikes will have at least front suspension if not full suspension. Should you wait to buy a suspension bike? Like computers, bikes are making huge advances in technology. This is nowhere more prevalent than in suspension and brake technology. Our advice is to get the best you can afford now, and then ride it till it dies. By the time that happens, bicycles will perhaps be made out of paper and able to climb cliffs. Ok. Maybe not. But who would have predicted you'd be getting information like this from a computer linked to REI?