STX 36 Twin Rear Shock Absorber Set - HD 220

Item Summary Piston diameter:36 mm Length:340 mm Stroke:88 mm Rate N/mm:32 N/mm Mounted spring:21180-01 Packaging unit: pair About the Product hlins STX 36 Twin Rear Shock Absorber Set HD 220 340 mm Black for Harley-Davidson Dyna FXD Series (19912017) Premium Suspension Performance for Harley-Davidson Dyna Models The hlins HD 220 STX 36 Twin Rear Shock Set is engineered to deliver a significant improvement in ride quality, handling precision, and rider confidence for Harley-Davidson Dyna motorcycles equipped with 340 mm (13.4-inch) rear shocks. Combining hlins' legendary suspension technology with a sleek black finish, the HD 220 offers the perfect balance of classic styling and modern performance. Designed specifically for American V-Twin applications, these shocks utilize hlins' proven STX 36 Single Tube Technology, providing exceptional damping consistency, improved rear wheel traction, and superior comfort on everything from city streets to long-distance highway rides. Key Features Genuine hlins STX 36 Twin Rear Shock Set hlins Part Number: HD 220 340 mm eye-to-eye length Black springs and black shock bodies STX 36 Single Tube (S36E) monotube design 36 mm piston diameter High-pressure nitrogen gas charged Adjustable spring preload Precision hydraulic damping system Model-specific spring and valving calibration Fully rebuildable and serviceable Manufactured in Sweden STX 36 Single Tube Technology The HD 220 incorporates hlins' Single Tube Technology (STX), featuring a 36 mm piston operating within a high-pressure gas-charged hydraulic system. This design minimizes cavitation and maintains consistent damping performance under a wide range of operating temperatures and riding conditions. Compared to conventional OEM suspension, the STX 36 provides: Improved damping consistency Enhanced wheel control Better heat dissipation Reduced suspension fade Increased rear tire traction More predictable chassis behavior Superior rider feedback The result is a motorcycle that feels more stable, composed, and confidence inspiring throughout the entire ride. Emulsion-Type Damping System The HD 220 utilizes the S36E emulsion-type damping system, a proven design that combines outstanding reliability with excellent ride comfort and predictable suspension response. The emulsion configuration offers: Compact lightweight construction Smooth damping characteristics Excellent durability Low maintenance requirements Progressive suspension action Outstanding performance for street and touring applications Its simplicity and effectiveness have made the STX 36 one of hlins' most trusted twin-shock platforms for American V-Twin motorcycles. Adjustable Spring Preload Mechanical spring preload adjustment allows the suspension to be tuned for varying rider weights, passengers, and luggage loads. Proper preload adjustment improves: Chassis balance Steering precision Ground clearance Brake stability Cornering confidence Overall ride quality Correctly setting rider sag ensures the suspension operates within its intended range, maximizing both comfort and performance. Premium Engineering Every hlins shock absorber is manufactured using premium materials and precision machining techniques developed through decades of championship-winning motorsport experience. Construction features include: CNC-machined aluminum shock bodies Hard-anodized corrosion-resistant surfaces Precision-ground piston rods Low-friction seal head assemblies High-quality hydraulic oil Precision shim-stack valving Replaceable internal wear components Unlike disposable suspension systems, the HD 220 is fully rebuildable and can be serviced to restore factory performance for years of dependable operation. Performance Benefits Improved Ride Comfort Advanced hydraulic damping absorbs road imperfections more effectively than factory shocks, reducing harshness and rider fatigue during long rides. Enhanced Stability Controlled suspension movement minimizes chassis pitch and oscillation under acceleration, braking, and cornering. Increased Rear Wheel Traction Improved wheel control helps maintain tire contact with the road surface, enhancing grip and overall stability. More Predictable Handling The motorcycle responds more accurately to rider inputs, providing smoother transitions and greater confidence through corners. Reduced Suspension Fade The high-pressure gas-charged monotube design maintains consistent damping performance even during prolonged aggressive riding. Technical Specifications Specification Details Manufacturer hlins Racing Part Number HD 220 Type Code S36E Configuration Twin Rear Shock Set Shock Type Monotube Emulsion Piston Diameter 36 mm Length 340 mm Stroke 88 mm Spring Rate 32 N/mm Mounted Spring 21180-01 Position Rear Spring Preload Adjustment Yes Serviceable Fully Rebuildable Packaging Pair Fitment Designed for Harley-Davidson Dyna models utilizing the 340 mm long-version rear shock configuration, including: Dyna Super Glide Sport FXDX (19992005) Dyna Super Glide Sport FXDXI (20032004) Dyna Super Glide T-Sport FXDXT (20002003) Dyna Wide Glide FXDWG (19932008 Long Version) Dyna Wide Glide FXDWGI (20032006 Long Version) Compatible with select Harley-Davidson Dyna FXD Series models from 19912017 that utilize the 340 mm rear suspension configuration. Always verify your motorcycle's original shock length before ordering. Installation The HD 220 installs directly using the factory mounting locations without modification. For optimal performance, professional installation and suspension setup are recommended to ensure: Correct rider sag Proper preload adjustment Balanced chassis geometry Maximum ride comfort Optimal handling performance Proper setup allows the suspension to perform exactly as hlins intended across a wide range of riding conditions. Service and Maintenance Like all premium hlins suspension products, the HD 220 is fully rebuildable. Routine servicing includes replacement of hydraulic oil, seals, and wear components to restore original damping performance and extend service life. Regular maintenance ensures consistent ride quality and protects your investment for years of reliable operation. Why Choose hlins? For nearly 50 years, hlins Racing has been the benchmark for premium motorcycle suspension, earning championships in MotoGP, World Superbike, Endurance Racing, Motocross, and countless national racing series. Every street product benefits from this racing heritage, delivering exceptional comfort, control, and precision to riders around the world. For Harley-Davidson Dyna owners seeking a substantial upgrade in ride quality, chassis stability, and handling performance while maintaining a classic appearance, the hlins HD 220 STX 36 Twin Rear Shock Set is one of the finest suspension upgrades available.