Enter rider weight, bike weight, spring rates, fork & shock shim stacks (base valve, mid valve, rebound), bleed holes, LSV adjuster, compression adjuster, oil level, oil viscosity, and gas pressure.
The engine calculates three complete shim stacks for each circuit — Recommended, 5% Softer, and 5% Stiffer — using proper tapered stack construction with thinnest shims possible. Includes force-velocity curve overlays.
Generate a clean, printable report with all recommended stacks, cavitation analysis, spring rate suggestions, oil level recommendations, and simulation warnings — ready for the workbench.
Base valve compression, mid valve with float, rebound, LSV adjuster, bleed holes, oil level & viscosity effects.
Compression with adjuster stack, rebound, bleed valves, gas pressure. Stack height & adjuster dominance calculated.
Quarter-car dynamics with 12 track profiles — MX whoops, SX rhythm, enduro rocks, road race braking zones. Detects bottoming and excessive forces.
Iterative loop: calculate stacks, simulate, check for bottoming, adjust, re-simulate — until validated. Recommends spring rate and oil changes when shims are exhausted.
KTM / Husqvarna / GasGas (WP XACT, WP AER, WP PDS, WP Linkage), Showa SFF-Air, Showa TAC, Kayaba SSS, Sachs, Ohlins TTX, Marzocchi. Works with any shim-stack damper — just enter your stack and valve geometry.
Enter 3-point force-velocity data manually or upload a CSV from your suspension dyno (Restackor, shock dyno, fork dyno). The calculator fits your measured curve and shows it overlaid against the ideal target.
Rider weight, bike weight, spring rates, oil level, discipline
Fork & shock stacks, dyno data, bleed holes, float dimensions
Engine calculates, simulates on track data, auto-tunes until validated
Get 3 shim stacks per circuit, print the build sheet, revalve with confidence