Calcolatore Rapporto Marce Bicicletta — Formula

Bicycle Gear Ratios

The gear ratio determines how far the bike travels per pedal revolution and directly affects speed and effort.

Formula

Gear Ratio = Front Teeth / Rear Teeth

Development = Gear Ratio x Wheel Circumference

Speed = Development x Cadence x 60 / 1000

Higher ratios (big front, small rear) mean higher speed but more effort. Lower ratios (small front, big rear) are easier for climbing.

Esempio Risolto

50-tooth chainring, 17-tooth rear cog, 2.1 m wheel, 80 rpm cadence.

  1. Gear ratio = 50 / 17 = 2.94
  2. Development = 2.94 x 2.1 = 6.18 m per pedal turn
  3. Speed = 6.18 x 80 x 60 / 1000 = 29.6 km/h