Linear-Rate Springs Vs. Progressive-Rate Springs

A question we get asked a great deal is 'which springs are best for me, progressive rate or linear rate'? Well the answer to that is that their is no definitive answer it really depends on your type of bike, usage, riding style and personal preference, but to help you decide we have compiled the following information -

Spring Definitions -

Linear Rate - also known as straight rate or constant rate springs, are were the entire spring is wound at the same pitch, therefore every kg of force has the same effect on the spring throughout its length. For example, if it takes 25kg of force to compress the spring one inch it will take another 25kg (50kg in total) to compress it the second inch and so on until the end of the travel.

Progressive Rate - are wound progressively from a finer pitch at one end to a coarser pitch at the other, therefore having a rising rate resistance to compression. For example, a 15kg to 25kg progressive spring rate will take 15kg of force to compress the spring one inch, then an additional 17kg of force the next inch and so on until the end of the travel, the last inch takes an additional 25kg to compress it .

So Which Are Best?
The pro progressive spring lobby will advocate that you are getting the best of both worlds, you'll be getting a spring that can be soft enough at the start of travel to absorb small road bumps and provide a more 'comfortable' ride, yet still offering the firmness at the end of the travel to handle the big bumps and potholes, major loading under braking and preventing bottoming out. Progressive fork springs are a very popular for cruisers and sportstourers.

So why then do many people say that straight rate springs are better? What's the problem with progressive rate springs? The first problem is that sportsbikes and racing bikes simply do not have enough suspension travel to take advantage of the progressive rates. The initial softer part of the spring just gets used up straight away leaving a limited amount of travel for the stiffer portion to deal with, resulting in less compliance and less traction. The second problem is that damping rates need to be matched to the spring rates, inparticular rebound damping, with progressive rate springs this is impossible. Damping is always a bit of a compromise and adding progressive springs to the mix just makes the job so much more difficult.

For sportsbikes and racing bikes virtually all suspension tuners will recommend linear springs, you will be very hard pressed to find any who will argue for progressive rate springs but if you have cruiser or tourer then progressive springs may be the perfect option.