S&W motorcycle MX Vintage NOS rear shock spring set, AHRMA Single Rate 9\" Race For Sale - New and Used

This is an excellent find for a vintage motocross, flat track, or street motorcycle build! This set was included in the inventory of NOS parts from a motorcycle shop in Papillion, Nebraska that closed its doors decades ago, and was just recently reopened. Most of the bikes and parts are European and Japanese, much of it being race & performance parts.S&W Engineered Products was one of the premier suspension and spring manufacturers during the 1970s and 1980s AMX/vintage dirt bike boom. They supplied high-quality aftermarket single-rate and progressive springs to fit their own shock bodies, as well as popular setups like Girling, Boge, and early Fox Shocks.Here is what your specific configuration and markings indicate: Spec Breakdown & Color Coding Dimensions: A 9-inch free length combined with a 1.5-inch inside diameter (I.D.) makes this spring a universal fit for several classic twin-shock motorcycles from the mid-to-late 70s. Single Rate: Unlike progressive springs (which feature tighter coils at one end to change stiffness as they compress), a single-rate spring has even spacing across the entire length. This provides a highly predictable, consistent resistance throughout the suspension stroke.The Markings (Gold/Red/Gold). S&W utilized a paint-stripe color code system sprayed across the active coils to identify the spring\'s rate (measured in pounds per inch) without needing to stamp the metal. While exact comprehensive master charts for S&W are rare today, a Gold/Red/Gold combination typically signifies a mid-to-heavy tier spring rate designed to accommodate adult riders or heavier vintage machinery.

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