Mountain bike suspension is no different than on your car. It is meant to soak-up the rough spots and give the driver a smoother ride and more control of the vehicle. Your auto undoubtedly has springs and shock absorbers. The springs are meant to absorb the bumps and the shock absorbers slow down the rebound (called dampening).
Many low quality bikes have only springs and no dampeners. When the rider hits a bump the spring may absorb the energy … but no dampening means the bike will instantly rebound in the opposite direction (Newton’s Law), throwing the rider upward, possibly causing a loss of control.
The best bike shocks are usually filled with air (to give you a cushion on compression) and a piston immersed in a thick oil (to slow the rebound). Unlike on a car the spring and dampening components on a bike are often combined into one unit and just called a “shock.”
Most mountain bike shocks have buttons or small levers to adjust for stiffness and rebound speed of the shock.
So, how much mountain bike suspension do you want? The following offers advantages and disadvantages of front and rear suspension.
I am not sure if I have ever seen a true mountain biker on a trail without front suspension. Okay, I started out riding an old GT Ventana, which had had no front or rear suspension. I rode that thing to places I cannot believe at this time. But I do not consider myself a true mountain biker back then!
Rear Suspension Only
During a visit to Arkansas I got a chance to ride with Misty Murphy, the Cat 2 Arkansas State Champion for 2013. During that ride Misty rode a bike with only front suspension, or what is commonly referred to as a “hardtail.”
In contrast, I am not sure I have seen any rider in Tucson on a hardtail. The difference? The terrain in Arizona is much different than in Arkansas. In Arkansas the trail surfaces were supreme, a finely crushed rock coated each path … trails built for speed. Riding Tucson trails requires bouncing off of rocks and other rough surfaces. Seldom does one find a long stretch of smooth riding. But there are some other reasons for riding a hardtail.
Advantages of a Hardtail
Less moving parts. Less moving parts means less maintenance and fewer parts to wear out.
Less weight. Suspension means more parts. More parts means a heavier bike.
Better climbing. A lighter bike is easier to pedal up a hill. In addition, if a rear suspended bike sags when pedaling (often called pedal bob) the rear shock is compressing and expanding, causing a loss of energy. If some of the energy (provided by your legs) is lost to compressing the shock, then less energy goes toward riding up the hill. This effect is most noticeable when climbing a steep hill, when our body weight falls more to the rear wheel, and when energy is usually at a premium.
A rear sagging bike also places the front wheel higher, which causes an increase in the uphill slope and presents more opportunities for the bottom bracket a hit a rock (for this reason most rear shocks have a setting to make them stiff for uphill climbing, and soft for bouncing down rough terrain).
Cheaper Price – Hardtails generally cost several hundred dollars less than a rear suspended bike.
On our Tabeguache trip, one of my fellow bikers (Nate) had only front suspension. However … he rode a custom-fit, $9,000 titanium bike, made just for him. He said the titanium frame soaked up most of the bumps. He was quite a rider, but only 29 years old.
Are you 59 years old? I am, and … any bike I ride will have rear suspension. My middle-aged body needs front and rear suspension … Full Suspension!
The advantages of rear suspension can be summed up in two words … comfort and control.
Jens Jensen, an engineer who has been riding mountain bikes for over 30 years says, “With the high quality and light weight of rear suspension these days, I can see no reason why anyone would not want to have it.”
Can ride harder and faster over rough terrain.
Need less ibuprofen the next day.
More things that could go wrong with the bike.
Now it is your decision … what type of riding will you do and what type of suspension will you find necessary? Get out there and demo some bikes with different suspension set-ups.
Mountain bike suspension … you decide!