Progressive Heavy Duty Fork Spring Kit For Harley-Davidson 39mm Fork

Progressive Heavy Duty Fork Spring Kit For Harley-Davidson 39mm Fork—Sportster, FXR, and Dyna

The 39mm fork is a wonderful upgrade from the 35mm unit it replaced, but it can display shortcomings when pushed hard, especially for loaded touring, when used on heavy Big Twins, or if routinely riding with a pillion. Progressive has a solution.

• Heavy-duty version of Progressive Suspension's progressively wound fork springs
• Cost-effective yet substantial increase in front end ride quality
• Kit includes springs, preload spacers, and instructions
• Can improve front end stability and brake dive
• Ideal for heavier riders or those looking for a firm, high-performance feel out of their forks
• A fork seal kit and fork oil are necessary to install this kit (both available separately)

Mushy response, brake dive, and bottoming can all but vanish with Progressive's Heavy Duty Fork Springs.

A progressive rate spring has the advantage of a rapidly rising resistance to compression. The benefit of this is that the spring can be soft enough at the start of the travel to offer a nice ride, yet as travel runs out, be firm enough to fight off the really big bumps.

These progressively-wound springs with spring rates that are higher than stock will reduce front end dive under braking and provide excellent ride comfort by eliminating uncontrolled suspension cycling.