Track cycling
Track bike gear calculator.
Type a chainring and a cog and you get the development. Set the speed and cadence you want to ride at and it tells you which gears put you there. Everything updates as you type.
Chainring and cog
- Development
- 7.82 m
- Gear inches
- 98.0
- Ratio
- 3.71
Drivetrain efficiency: 97.8 %. Bigger chainrings and cogs lose less.
Speed and cadence
This gear at 105 rpm
49.3 km/h
This gear at 60.0 km/h
128 rpm
Gears for 60.0 km/h at 105 rpm
Gear chart
Metres per pedal revolution with a 700 × 23c tyre. Tap a cell to load it above.
| Ring \ cog | 12 | 13 | 14 | 15 | 16 |
|---|---|---|---|---|---|
| 64 | |||||
| 62 | |||||
| 60 | |||||
| 58 | |||||
| 56 | |||||
| 54 | |||||
| 52 | |||||
| 50 | |||||
| 48 | |||||
| 46 |
Development = chainring ÷ cog × wheel circumference. Gear inches are the ratio times the wheel diameter in inches.
This tells you which gear turns at which cadence. It can’t tell you your optimal cadence.
SuperRecord can: it models the pursuit lap by lap with your CdA, CP and W′, with the standing start and the lean in the turns inside the model, and picks the gear that wastes the fewest watts at your cadence. See it in the demo, no sign-up.
How it is calculated
Development is how far the bike travels per full pedal revolution: chainring divided by cog, times the wheel circumference. With 52 × 14 and a 700 × 23 tyre that is 7.82 metres; in gear inches, 98.
Cadence at a given speed follows from that: 60 km/h is 16.7 m/s, divided by 7.82 m gives 2.13 revolutions per second, 128 rpm. That is why a 60 km/h pursuit is ridden on 9 to 10 metre gears, not 7.8.
Drivetrain efficiency comes from the Spicer and Kidd model: the bigger the chainring and cog, the less the chain articulates and the less is lost. Between two equal gears, the one with the bigger cog wastes fewer watts.