Diaz Suspension Design

Runt Cartridge - Fox Podium

Diaz Suspension Design Runt Cartridge - Fox Podium upgrades compatible forks with a dual-chamber air spring that targets a more linear, coil-like spring curve while keeping the tunability and easy service of an air setup. Built around a secondary air chamber with its own valve, it lets riders add controlled progression for bottom-out resistance without relying solely on volume spacers—useful for aggressive riding, heavier riders, or anyone chasing better mid-stroke support without the weight and commitment of a full coil conversion.

Key performance advantages for modern Fox 36 / Z1 Air forks

1. Dual-chamber air spring - Tunes a near-linear compression curve for a more “coil-like” feel while preserving air-spring adjustability
2. Independent progression control - Secondary chamber and valve add tunable bottom-out resistance without over-stiffening the initial stroke
3. Supple off the top with stronger mid-stroke support - Helps maintain traction and chassis support through repeated hits and compressions
4. Weight-conscious alternative to coil conversions - Listed at roughly 1/2 lb lighter than common coil conversions while staying close in weight to comparable spacer/token setups
5. Drop-in installation and air-spring compatibility - Designed to keep the fork’s air-spring functionality and simplify setup changes compared to a full spring-system swap

Fit notes: The 36mm version fits 2018+ Fox 36 forks with the NA2 air spring and Marzocchi Z1 Bomber Air forks. Not compatible with NA1 air springs, Z1 Coil forks, or Fox 36 E-Bike forks.