Gear Ratio Calculator
Find your final reduction. Compare gearing for speed and torque multiplication.
Calculate Gear Ratio
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Kart Speed Calculator
Calculate theoretical kart speed from engine RPM, sprockets and tire size.
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Quarter Mile Calculator
Explore empirical elapsed-time and trap-speed estimates from power and weight.
Calculate Quarter Mile
Tire Size Calculator
Compare tire dimensions, sidewall height and geometric circumference.
Calculate Tire Size
Torque to Horsepower
Connect torque, engine RPM and power with a transparent calculation.
Calculate Torque to Horsepower
Chain Length Calculator
Estimate chain pitches, even link count and center-distance adjustment.
Calculate Chain LengthALL RACING DISCIPLINES
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PERFORMANCEGo-kart gearing: acceleration versus top speed
More reduction increases ideal wheel torque for a given engine torque, while lowering wheel speed at a given engine RPM. Neither relationship alone predicts lap time.
Oct 18, 2026 · Technical guide
ENGINEERINGGo-kart jackshaft gearing explained
For a compound jackshaft, multiply the engine-to-jackshaft reduction by the jackshaft-to-axle reduction. Two sprockets fixed to one shaft share RPM.
Oct 18, 2026 · Technical guide
RACING BASICSTorque versus horsepower: one operating point at a time
Torque measures turning moment. Power measures work per time and equals torque multiplied by angular speed, so RPM is essential when converting one to the other.
Oct 18, 2026 · Technical guide
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QUICK ANSWERS
How our tools work Before you run the numbers.
Are the tools free?
Yes. All 36 calculators are free and require no account. Copy results or share a link containing your inputs.
Does theoretical speed predict actual top speed?
It describes wheel travel at an entered RPM. Available power, traction, drag and slip determine whether that operating point is attainable.
Can I use metric and imperial units?
Yes. Input controls convert between unit systems; results always state their units. Road-speed tools include MPH and KPH.
How do I calculate a go-kart gear ratio?
Divide driven teeth by driving teeth: 60 rear teeth ÷ 12 front teeth = 5:1. Multiply any additional reduction stages.
Physics formulas and standard unit conversions follow authoritative references from NIST (Guide for SI Units), OpenStax Physics and NOAA Weather Equations. Read our detailed Calculation Methodology & Sources.