Bicycle gear rollout worksheet
Mistake: Entering wheel diameter instead of circumference.
Fix: Measure one complete loaded wheel revolution and enter its travel distance.
Calculators · Free
Bicycle gear rollout worksheet
Calculate one selected gear’s wheel travel and theoretical speed from cadence.
01Enter your values
Runs in your browserRuns offline in your browser. Once the page and required files have loaded, processing needs no internet.
02Bicycle gear rollout worksheet
Runs in your browser
How it works
Calculate one selected gear’s wheel travel and theoretical speed from cadence.
L = C × Nf/Nr
One chain-driven gear with no internal hub ratio or wheel slip. Use measured loaded wheel circumference, not a tyre name. Coasting, losses, terrain and rider power are excluded. Works offline after loading.
Your data stays yours
Inputs are processed on this page and are never sent to a server.
About this tool
Use tool ↑Calculate one selected gear’s wheel travel and theoretical speed from cadence.
Gear ratio = chainring teeth / rear sprocket teeth. Rollout per crank revolution = measured wheel circumference × gear ratio. Speed = rollout × crank revolutions per minute, converted to distance per hour.
How to use it
- Enter your values
Loaded wheel circumference · Chainring teeth · Rear sprocket teeth · Crank cadence
- Calculate / generate
Calculate one selected gear’s wheel travel and theoretical speed from cadence.
- Result
Gear ratio: 2 Rollout per crank turn: 4.2 m Theoretical speed: 22.68 km/h
Calculation method
- Gear ratio = chainring teeth / rear sprocket teeth.
- Rollout per crank revolution = measured wheel circumference × gear ratio.
- Speed = rollout × crank revolutions per minute, converted to distance per hour.
L = C × Nf/Nr
Bicycle gear rollout worksheet
- Loaded wheel circumference
- 2100 mm
- Chainring teeth
- 50
- Rear sprocket teeth
- 25
- Crank cadence
- 90 RPM
Result
Gear ratio: 2 Rollout per crank turn: 4.2 m Theoretical speed: 22.68 km/h
Frequently asked questions
What does this result assume?
One chain-driven gear with no internal hub ratio or wheel slip. Use measured loaded wheel circumference, not a tyre name. Coasting, losses, terrain and rider power are excluded. Works offline after loading.
Where does my data go?
Calculations run on your device. Form inputs are not sent to a server.
Terms and definitions
Enter your values
- Measurement system
The initial choice follows your browser region. Your choice is remembered on this device. Gallons are US gallons. Switching units keeps your numbers unchanged and interprets them in the new unit.
Numbers stay unchanged. Check the new unit and enter the intended measurement, or select an example for that system.
- Loaded wheel circumference
Measured travel of one loaded wheel revolution.
Enter a numerical value for this quantity. Use the unit shown beside this field. mm / in
Minimum: 1e-9 · Maximum: 1000000000000 mm
- Chainring teeth
Positive whole tooth count on the front chainring.
Enter a whole number; fractional counts are not valid.
Minimum: 1 · Maximum: 1000000
- Rear sprocket teeth
Positive whole tooth count on the selected rear sprocket.
Enter a whole number; fractional counts are not valid.
Minimum: 1 · Maximum: 1000000
- Crank cadence
Crank revolutions per minute; zero represents no pedaling.
Enter a numerical value for this quantity. Use the unit shown beside this field. RPM
Minimum: 0 · Maximum: 1000000000000 RPM
Result
- Result
Gear ratio = chainring teeth / rear sprocket teeth. Rollout per crank revolution = measured wheel circumference × gear ratio. Speed = rollout × crank revolutions per minute, converted to distance per hour.
Calculated from your entries using the method below.
- Gear ratio
Front tooth count divided by rear tooth count.
Calculated from your entries using the method below.
- Rollout per crank turn
Theoretical forward travel for one complete crank revolution.
Calculated from your entries using the method below.
- Theoretical speed
Rollout multiplied by crank cadence.
Calculated from your entries using the method below.
- Value
Gear ratio = chainring teeth / rear sprocket teeth. Rollout per crank revolution = measured wheel circumference × gear ratio. Speed = rollout × crank revolutions per minute, converted to distance per hour.
Calculated from your entries using the method below.
- Unit
Gear ratio = chainring teeth / rear sprocket teeth. Rollout per crank revolution = measured wheel circumference × gear ratio. Speed = rollout × crank revolutions per minute, converted to distance per hour.
Calculated from your entries using the method below.
Common mistakes and quick fixes
Limits and key assumptions
- One chain-driven gear with no internal hub ratio or wheel slip. Use measured loaded wheel circumference, not a tyre name. Coasting, losses, terrain and rider power are excluded. Works offline after loading.
- Displayed results may be rounded; rounding does not add measurement precision.