Observed arrival · 2026-09-19
VeloCalc: A Physics Engine for Bicycle Gearing
A Chinese-language bicycle gearing calculator that models cadence, speed, power, climbing limits, and drivetrain trade-offs.
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●Pro
◎Niche
◉Human
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ƒJS
- For
- Road, mountain, gravel, and fixed-gear cyclists
- Worth noticing
- It models gearing alongside aerodynamic drag, rolling resistance, slope, rider mass, and FTP thresholds.
Field notes
The homepage describes a parameter-driven model rather than a simple gear-ratio lookup. Its inputs include wheel and tire dimensions, rider and bicycle mass, FTP, gearing, and slope, while its outputs include cadence-speed curves, gear-step percentages, climbing limits, and drivetrain overlap. Presets are listed for major Shimano, SRAM, Campagnolo, and GRX groupsets. The site also states that configurations persist locally and can be used through an offline PWA.
Observed signals
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Editorial observations of this landing page, not a rating.
○OpenPublic substance visible
✦PrettyNotable craft visible
●ProPolished or operationally mature
◎NicheUnusually specific use
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