Progressive’s 412 Series shocks combine great price with awesome performance.

418 Series shocks offer five rebound damping and four spring pre-load settings.

hen the stock air shocks on their 1980-2004 FLH baggers wear out, most riders assume they should replace them with another set of air shocks. For a number of years Progressive Suspension sold a replacement air shock for this application, but discovered over time that steel-spring shocks work much better. The reason is the FLH’s rear shocks lower mounts are located behind the rear axle, resulting in a poor “lever ratio,” which is the relationship between shock travel and rear wheel travel. Air shocks with big seals have a lot of “stiction” and resist very small movements. Steel-spring shocks, however, have smaller seals that allow smoother shock movement, resulting in a more controllable and comfortable ride in addition to superior damping performance
     Progressive Suspension’s recommended steel-spring shocks to replace the stock air shocks include the 412 Series, a steel-bodied shock with multistage, velocity-sensitive internal valving that comes in chrome or black powdercoated end caps and springs; the aluminum-bodied, gas-charged 418 Series with external rebound damping adjustment; and the top-of-the-line 440 Series with the advanced shock technology of the Inertial Active System (IAS) licensed from Edelbrock. They come with polished and anodized aluminum end covers (also available in powdercoated black), no-tool spring preload adjustment, and a limited lifetime warranty on the shock and springs.
     Progressive Suspension offers 412 and 418 shocks up to 1.5 inches shorter than stock for riders who want to lower their bikes, while the shortest recommended IAS shock is 12 inches.
     When it comes to FLH Harleys, the high quality and outstanding performance of Progressive Suspension’s steel-spring shocks blows the stock air shock away. Contact your Drag Specialties rep for more details.

The 440 I.A.S. is Progressive’s top-of-the-line shock.