Cycling Tools & Calculators

Frame size, Gear ratio, Skid patches, and Speed calculators

Frame Size Calculator

Find your ideal frame size based on measurements

Gear Ratio Calculator

Calculate gear ratios, gear inches, and speed/cadence values

Skid Patch Calculator

Calculate the number of skid patches on your rear tire

Speed/Cadence Calculator

Calculate speed from cadence or required cadence for target speed

Tire Pressure Calculator

Calculate optimal tire pressure based on weight, tire size, and riding conditions

Frame Size Calculator

Find your ideal frame size based on measurements

📏 How to Measure Inseam:

  1. Stand barefoot against a wall with feet 6-8" apart
  2. Place a book between your legs, spine up against crotch
  3. Press firmly upward as if sitting on a saddle
  4. Mark the wall at the top of the book
  5. Measure from floor to mark - that's your inseam!
84 cm

Recommended Size

56 cm

LRange: 54-58 cm

  • Test ride recommended for final decision.

Gear Ratio Calculator

Calculate gear ratios, gear inches, and speed/cadence values

700c ≈ 678mm (622mm BSD + 2×28mm tire)

Primary Metrics

Ratio:2.82:1
Gear Inches:75.4
Gain Ratio:5.63
Meters of Development:6.01 m
Skid Patches:34

Speed @ Cadence

60 RPM:21.7 km/h
80 RPM:28.9 km/h
90 RPM:32.5 km/h
100 RPM:36.1 km/h

Skid Patch Calculator

Calculate the number of skid patches on your rear tire

What are skid patches?

Skid patches are the specific points on your rear tire that make contact with the ground when you skid. More patches = longer tire life.

Total Skid Patches

Basic patches (one foot)

34

Tire Life Multiplier

34x vs no patches

Recommendation

Excellent tire life! Great cog choice for longevity.

Patch Distribution

Speed/Cadence Calculator

Calculate speed from cadence or required cadence for target speed

700c ≈ 678mm (622mm BSD + 2×28mm tire)

Cadence Zones:

  • Recovery (< 70 RPM)
  • Endurance (70-90 RPM)
  • Tempo (90-110 RPM)
  • Sprint (110+ RPM)

Result

Speed @ 90 RPM

32.5 km/h

20.2 mph

Ratio: 2.82:1

Meters per minute: 541 m

Comprehensive Speed/Cadence Table

Cadence (RPM)Speed (km/h)Speed (mph)
5018.011.2
6021.713.5
7025.315.7
8028.917.9
9032.520.2
10036.122.4
11039.724.7
12043.326.9
13046.929.1
14050.531.4

Tire Pressure Calculator

Calculate optimal tire pressure based on weight, tire size, and riding conditions

Weights

Backpack, water bottles, tools, etc.

Front Tire

Measure internal width of rim

Rear Tire

Riding Conditions

More RearBalancedMore Front

Recommended Tire Pressure

Front Tire
0
PSI
=
0
bar
Rear Tire
0
PSI
=
0
bar
Acceptable Range
Front:-5 - 5 PSI
Rear:-5 - 5 PSI

System Summary

Total Weight:80 kg
Front Load:36 kg
Rear Load:44 kg

💡Tips & Recommendations

    ℹ️Important Note

    These are calculated recommendations based on industry formulas. Always check tire manufacturer's min/max pressure ratings. Adjust based on personal preference and road feel.

    Scientific References & Methodology

    Calculation Method

    Base Formula
    PSI = (Load_lbs / Tire_Width_mm) × 27.5
    Correction Factors
    • Tire Width: 0.75× - 1.10×
    • Rim Width: 0.97× - 1.03×
    • Riding Style: 0.90× - 1.10×
    • Terrain Type: 0.88× - 1.0×
    • Wheel Size: 0.98× - 1.02×
    Weight Distribution
    Typical road bike: 45% front, 55% rear. Can vary based on rider position and bike geometry.

    References

    Frank Berto
    Pioneering research on optimal tire pressure based on load and tire width. Foundation for modern pressure calculations.
    Read More
    Silca Tire Pressure Calculator
    Advanced tire pressure research combining rolling resistance, comfort, and aerodynamics data.
    Visit Calculator
    Bicycle Quarterly
    Extensive real-world testing of tire pressure effects on speed, comfort, and handling.
    Learn More
    Industry Standards
    ETRTO (European Tire and Rim Technical Organization) and ISO standards for tire pressure recommendations.
    🔬Validation & Cross-Reference

    This calculator's results have been validated against multiple industry sources including Silca, Rene Herse, and manufacturer recommendations. For critical applications, always cross-reference with at least two other sources and consult tire manufacturer specifications.

    Tools - Fixed Gear Calculators | moshpit.cc