Nasty Fast Parts · Tech Tools

Calculators v84

Build, compare, and save settings for your two-stroke ATV. All six tools share the same named build JSON files and browser-local build library.

Jetting Calculator

Model carb jetting, fuel, reeds, expansion pipes, intake and tuned recommendations.

Gearing

Sprockets, tires, transmission ratios and speed versus RPM.

Premix

Gasoline/oil mixture quantities and an RPM, displacement and oil-viscosity guide.

Compression & Squish

Geometric and trapped compression, squish dimensions, estimated flow velocity.

Carburetor Size Selector

Compare three carburetor sizes for Trail, Median and Race.

Engine Build Simulator

Estimate a two-stroke powerband, torque and HP with explicit assumptions.

Keep the entire folder together when uploading. The calculators share machine-data.json and nfp-build-store.js. On another device, use Export JSON and Import JSON to transfer saved builds.