Sprindex: Adjustable Coil Spring Rate on the Fly 8

Sprindex is a new coil spring system that, for the first time, allows riders to adjust and fine-tune the spring rate of their coil shock. No tools required! Imagine a coil shock where you can quickly adjust the spring rate without changing springs. This addresses the primary reason why many riders and bike companies have been avoiding the greater performance of a coil shock over an air shock. 

Almost everyone agrees that coil shocks outperform air shocks, assuming the correct spring rate for the rider. So why do air shocks currently dominate mountain biking? Mostly because of lack of spring rate adjustability. 

Coil spring rates have always been fixed and are usually available in increments of 50 lb/in (a few at 25 lb/in). The odds, for example, that 400 or 450 lb/in is the optimal spring rate for any particular rider is small. There is a noticeable difference between rates of under 10 lb/in, and it can be the difference between a positive experience with the suspension or not. If the spring is too soft, it might bottom out and so most people tend to ride springs that are too stiff, providing a harsher ride and not reaching full suspension travel. Even if every spring rate was available, how would a rider know which spring to order? Furthermore, the best spring rate could be different for two different trails.

How does it work? Spring rate is determined by four factors: wire diameter, coil diameter, material, and the number of active coils. Fewer active coils make for a stiffer spring. Twisting the Sprindex adjustment dial varies the number of active coils. Adjustment is done by hand and without tools. Sprindex springs are also lighter and more durable than ordinary steel springs because they are made with the highest tensile steel available and designed for the stress of the highest possible adjusted spring rate. Sprindex is available in three different lengths to fit nearly every mountain bike coil shock on the market. MSRP is $140 USD and is available at local bike retailers and Sprindex.com.

Sprindex is a new company from the original founders of Crankbrothers (Carl Winefordner, Frank Hermansen, Andrew Herrick) and freeride legend Richie Schley. Sprindex was invented out of frustration which lead to the question, "why can't there be an adjustable coil?" Sprindex is the answer.