MX Midwest – Suspension Buyer Guide
The world of ATV suspension has probably changed more in the last few years than any other component of the racing ATV. Each year the suspension companies create new innovations that push the boundaries of how good a shock can be and how much it can cost. Here are some of things to look for when buying premium suspension.
Why Aftermarket
Factory suspensions just aren’t good enough for real competition. They are set up with a very broad range of terrain and rider weights in mind. The OEM companies need for these shocks to work for the widest range of riders possible, considering this, they actually do a pretty good job but just aren’t good enough for a full on racing environment. Aftermarket manufactures only need to make your shock work for you, making them much more specialized. These shock absorbers are custom made for your weight, your specific a-arms and swingarm, type of terrain and skill level, and yes, this all makes a difference.
Standard or Long Travel
You hear about standard travel and long travel suspension, so what does it mean? Standard travel shocks (front) are designed to fit on the factory a-arms without changing or modifying any OEM mounting points. Unlike the name suggests aftermarket shocks that fit the OE mounting points usually offer extended travel over the factory shock absorbers and may even be slightly longer if your make and model has the clearance. There are also standard travel aftermarket a-arms that have increased width but have the standard shock clearance. Long travel setups require special a-arms that have relocated suspension mounting points that allow for a longer shock to fit between the a-arms and frame. The same idea goes for the rear except a new extended linkage or linkage/swing-arm combo allows for a longer shock.
Why you ask? Although a long shock does make slightly more wheel travel, their shock bodies hold much more oil and operate longer without heating up. The main benefit over a long travel aftermarket shock has over a standard travel aftermarket shock is this increased internal oil volume. It can operate more efficiently longer, professional racers need their suspension to operate the same on the last lap of a race as they do on the first lap. A standard travel aftermarket shock has this same advantage over an OEM shock, plus may offer additional or more functional adjustments like rebound and compression adjustments.
No-Preload/SAG
This option does exactly what the name suggests. Aftermarket racing shocks may be equipped with a no preload option meaning that there is little or no spring tension on the coil spring if it is not being compressed by obstacles. This allows the shock absorber to sag to a lower ride height, meaning a lower center of gravity for both better cornering and better handling. Since there is no downward pressure on the coil spring it also means the shock is not trying so hard to rebound. This makes for a less harsh ride and reduced kick back from the suspension. Off the track many riders may not want this option. A no preload style shock can pack up under extended bumpy or trail conditions. Since the shock sets so much lower to the ground the travel extends away from the ATV when the chassis leaves the ground much like you may have seen in off road truck races. If the ATV continually hits bumps without being allowed to extend its’ suspension travel the shocks will bottom out, hence “packing up”. No preload shocks are meant for racing only.
How about Compression and Rebound?
Although the shock absorbers on most new ATVs include a compression and rebound adjustment they are typically a step below the quality of that on a premium aftermarket shock. Compression adjustment is how resilient the shock is against compressing “pushing together”. Often referred to as hard and soft, a compression adjusted very hard makes for a rough ride but is much harder to bottom out. Compression set very soft makes for an extremely smooth ride at slow speeds but bottoms out extremely easy at high speeds or on jumps and actually causes a rough ride as well. Many riders prefer a neutral compression setup, meaning that the compression isn’t really hard and may bottom out on occasion but isn’t so soft that the shock isn’t functioning properly. If your compression is set neutral you can usually make a quick click or two in either direction to satisfy your needs when you visit different tracks. Professional riders generally have a very stiff compression due to the amount of impact their ATVs take from landings, however this usually isn’t suggested for lower ranked riders or hobby riders.
Extremely race oriented shocks may also have a dual speed compression, hi/low speed. This doesn’t refer to how fast the ATV is going when the compression works. It is simply an even more in depth way to dial in how the suspension compresses over different types of obstacles. This setup can also go over the head or riders without a lot of setup experience, as it can be difficult to dial in without the right knowledge.
Rebound on the other hand is how quickly the shock returns to its’ extended or normal length after it has been compressed. This is usually referred to as Fast and Slow adjustment. Normally racers want a slow rebound; this keeps the ATV from bucking through obstacles like a whoop section and breaking bumps or after a hard landing. A fast rebound can actually throw a rider from his ATV after a hard hit, especially if the rear shock is adjusted wrong. If the rebound is to slow the shock will pack up as mentioned above. Optimal rebound should be just fast enough to return your shock to normal length between obstacles and no more. Premium shocks that do not have rebound adjustment typically have a pretty good factory setting. Suspension rebound is also more general than compression for most riders, meaning that it isn’t frequently or as widely adjusted as compression. Many riders wishing to save money will purchase shocks with a compression adjustment but no rebound adjustment, although we normally advise riders to always get a rebound adjustment on the rear shock absorber.
Piggybacks or Remote Reservoirs
First let’s take a look at what they do. They both are simply a remote storage location for excess shock oil and a nitrogen bladder. The body of your shock gets very hot during a race; it actually has a piston that slides up and down just like the cylinder inside an engine. This hot oil is pushed in and out of the reservoir as the shock compresses and rebounds. The nitrogen bladder helps cool the oil and ad pressure to the system. Remote reservoirs are exactly the same as piggyback reservoirs except they mount remotely away from the shock and are connected by a hose, not actually attached to the body of the shock like a piggyback.
Most people see no advantage in performance between the two. They both have their ups and downs. A piggyback shock makes for easier installs and removal at the track although the reservoir usually hangs right out in the open and can more easily be damaged during a crash. Sometimes their isn’t room for remote reservoirs on a machine’s chassis and sometimes piggybacks wont clear some brands of aftermarket upper a-arms. It’s really a toss up as to what you personally like. For this season some of the new shocks out there are only being offered as piggybacks.
