You’ve been riding your bike for a while now, and you are starting to wonder if you need different springs for your bike. But do you even need new springs? Or how do you tell if you need softer or stiffer? Scour the internet and you can get a multitude of different answers. But fear not, here’s some info to get you going on the right track!
At the top of the list for spring selection is sag. The purpose of sag is to help get your suspension to operate (move) in the proper portion of the fork and shock stroke. Your springs, along with preload, determine where this operation takes place. Getting optimal sag numbers will help determine whether you have the correct springs or not. If you are unsure as to what numbers to use, most companies, e.g. K-Tech, Bitubo, Ohlins, will give you numbers to work with in their install manuals. Another option is to consult your local suspension guru.
What’s your free Sag?
Once you’ve set your sag, the next step is to check free sag. Free sag is the amount the suspension compresses under the bikes weight from fully extended. Many times you can still get your sag numbers, but free sag may be out of tolerance. If that’s the case it may be time to look at different springs and change the preload settings. Generally, too little free sag means you should go to a stiffer spring with less preload. Too much free sag means it’s time to look at a softer spring with more preload. Again, consult your install manual or local suspension shop for guidance on proper free sag numbers.
Know your weight and pace.
When picking springs for your bike, many will tell you your weight is the main factor in choosing springs. Yes, your weight plays a big factor, but there is another crucial part of the equation, your pace. Springs are there to support the weight of you and the bike. In addition, they need to support the downward forces of the throttle and brake application; and as your pace increases, so do these forces. If you’ve ever conversed with a suspension shop, two questions they will usually ask for is rider weight, AND pace. With this key information, your spring selection will be much easier.
Progressive or linear.
We get this question quite a bit. Progressive rate or linear rate springs? The short answer is always use linear rate springs! Progressive rate springs make tuning damping difficult, and sometimes can give an inconsistent feel. Plus with the right spring and preload you can make linear rate spring act just like a progressive rate spring.
Just add preload!
Ever hear this phrase? “You don’t need new springs, save your money and just add preload!” There are a couple issues with this statement. First, when you add too much preload, you lose free sag. Besides a telltale for the right springs, free sag provides other important qualities to for max grip. So when you crank away on preload, you could possibly make handling worse. And second, a soft spring with excessive preload will feel harsh over small bumps and not provide you with bottoming support. A better option is to go to a stiffer spring with less preload. Less preload allows the spring to move over small bumps and dips, all while keeping the forks off the bottom when you’re hard on the brakes.
Selection of the right springs can be a somewhat daunting task. Following the above guidelines will not only help you figure out if you need springs, but also what direction you need when picking rates. So go out and check your ride, you’ll thank yourself when your on the street!