Lainer Suspension Leaf Spring Mid-Valve Upgrade For Showa 49mm Forks
Give your Showa 49mm forks the control and precision they deserve. The Lainer Suspension Leaf Spring Mid-Valve Holder replaces the OEM spring design with a modern leaf spring setup, similar to the mid-valves found in modern KYB forks.
While the OEM coil-spring mid-valve setup allows for early shim deflection and softer initial damping—often leading to early blow-off—it is generally better suited for comfort-focused riding such as technical trails, off-road, or enduro use. This setup provides a plush feel at the expense of front-end support under aggressive load.
The Lainer leaf spring design delivers even and consistent preload across the shim stack, reducing early blow-off and enhancing low-speed hold-up. This results in a more controlled and responsive fork, ideal for motocross, supercross, and riders seeking precise handling and chassis stability.
Key Benefits:
-
Improved Low-Speed Hold-Up
Enhances ride height and support during braking, G-outs, and corner entry without harshness. -
More Consistent Damping Response
The leaf spring reduces deflection and provides a more consistent dampening response, improving overall predictability. -
Preserved Plushness
Because the leaf spring only affects initial shim movement, mid and high-speed compliance is maintained—no harshness, no stiffness, just control where you need it. -
Better Front-End Feel
Offers a more connected and confidence-inspiring ride across technical terrain and rough braking zones.
Why It Works
The leaf spring system adds preload to the mid-valve shims without needing to thicken or stiffen the entire stack. This added support increases damping at low shaft speeds (low-speed compression), but allows normal shim deflection under higher pressures. This means you get the hold-up of a firmer fork while keeping the comfort of a plush one.
Application:
CRF 250 2018-2025
CRF 450 2017-2025
KXF 450 2020-2025
RMZ 450 2017-2025













