GZYF 12.6" (320mm) Universal Motorcycle Rear Air Shock Absorbers — Nitrogen-Charged, Adjustable Preload

These 320mm eye-to-eye rear shocks combine a CNC-machined aluminum reservoir, steel-and-aluminum construction, and adjustable spring preload to deliver improved impact absorption and tunability over basic stock units. They are marketed as a universal fit for motorcycles with a 12.6" eye-to-eye measurement, making them a practical option for riders seeking enhanced comfort, stability or a visual upgrade.

Will these shocks fit my motorcycle?

Fit depends primarily on the eye-to-eye distance and mounting hardware. Confirm your current shock's center-to-center measurement is 320mm (12.6") and compare bolt diameters and bracket clearance before ordering.

• Eye-to-eye length: 320mm (12.6") — primary compatibility factor
• Suitable for many 150cc–750cc street bikes, scooters, mopeds, and some ATVs
• Check bolt size, mounting angle and clearance at swingarm and frame
• Use as replacement, style upgrade, or for custom bike modifications

How do these air/nitrogen shocks change the ride?

The combination of a nitrogen-charged damper and a larger external reservoir helps control heat and maintain damping consistency over extended use. That results in smoother absorption of small bumps and better control over larger impacts compared with typical stock shocks.

• Nitrogen/air damping reduces cavitation and improves rebound stability
• External CNC reservoir increases oil volume and heat dissipation
• Filters minor road imperfections while absorbing heavier hits
• Improved stability during acceleration and braking for safer handling

What adjustment options are available and why they matter?

These shocks include an adjustable spring preload that you change with tools to alter sag and ride firmness. Adjusting preload tailors compression feel during acceleration and changes how the bike sits under load, helping match the shock to different riders, cargo loads or riding styles.

• Tool-adjustable spring preload for quicker tuning
• Stiffer preload reduces sag for heavier riders or luggage
• Softer preload improves comfort for lighter riders or smoother roads
• Preload changes complement damping characteristics for balanced performance

What materials and build features affect durability?

The shocks use a mix of hardened steel components and aluminum alloy parts, plus a CNC-machined reservoir. Those materials balance strength and weight while the larger oil capacity and quality machining promote long-term reliability under regular riding conditions.

• Solid steel body and critical fasteners for structural strength
• Aluminum alloy and CNC reservoir for heat dissipation and lightness
• Precision machining for consistent sealing and performance
• Designed for replacement and aesthetic upgrade of stock units

Who is this for? The GZYF 12.6"/320mm rear air shock absorbers are aimed at riders who need a direct-replacement rear shock with improved damping, tunability and a sportier look. They suit owners of compatible 150–750cc road bikes, scooters, mopeds and quads who want better impact control, the ability to tune spring preload, and a durable reservoir-style design for longer, more consistent performance. Always verify your motorcycle's eye-to-eye measurement and mounting compatibility before purchase.