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Springs are another topic of long debate among riders. With few exceptions springs are helical wound, round wire metal with the front springs composed of two relatively long flimsy springs and the rear made short and stiff. Front springs must be able to support not only the weight of the rider and bike but also resist bottoming during hard braking. At the same time they must be soft enough to give good compliance during acceleration, when the weight transfers to the rear and the front is left skimming the road surface all the while fitting inside the fork tube. To meet these goals the springs must be long with abundant coils. Usually front springs are progressively wound. A simple progressive spring has its coils wound at two different pitches i.e. a coil every 3/4” versus’ a coil every 1”. In light loads all the coils are in use and the spring is soft. At heavier loads the closely wound coils bottom, becomes a solid cylinder, and the remaining larger spaced coils are left to handle the load. A spring’s tension rate, in inch lbs per inch, is inversely proportional to the number of coils being used. The fewer the coils the stiffer the spring rate. One way to think of this is it’s easier to bend a piece of rebar that’s 6ft long versus’ one 2ft long. Now you understand why when your 18yr old neighbor kid cut his springs to drop his car lower the car now bounces down the highway. The spring rate has been increased due to less coils but the damping rate remained the same. The springs are now overpowering the damping circuits.

Most manufactures use a progressive rate spring up front. Does it matter which way the spring’s sits in the fork tube? Only as it pertains to fitment but not to function. A spring doesn’t care one way or the other. In the aftermarket world most suspension tuners prefer straight rate springs. They are not trying to be all to everyone like a manufacture. They can better tailor the damping circuits to a straight rate spring with lower viscosity oil to achieve a better and more consistent response. More about oil later.
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