Gear Inch Bike Calculator
Calculate actual wheel/gearing combination mechanical gear-inch inventory, distinct from cadence→ground speed and not a fit recommendation.
Description
Gear inches combine loaded wheel diameter with the tooth ratio.
Gear inches combine loaded wheel diameter with the tooth ratio. They describe gearing rather than cadence or actual speed.1
The returned values include Gear inches by combination. The How section below explains the calculation, input rules and interpretation.
When to use Gear Inch Bike Calculator
Use Gear Inch Bike Calculator when you need to evaluate the supplied records under the calculation and evidence rules below. No bike-fit recommendation or measured rollout correction is inferred.
Prepare the observed race, match or training records and the stated units. Supply independently verified rule editions, calibration tables and targets where requested.
How to use Gear Inch Bike Calculator and understand its results
- Prepare the observed race, match or training records and the stated units. Supply independently verified rule editions, calibration tables and targets where requested.
- Enter measuredLoadedWheelDiametersInches, frontTeeth, rearTeeth using the field table and calculation rules, then run the tool.
- Read gearInchesByCombination. The explanation below defines the units, signs, ordering and any flags or placeholder values.
- If the tool reports an input issue, correct the values and run it again. Apply the stated assumptions when interpreting a successfully returned result.
| Input field | Meaning | Value type; see rules below | Requirement |
|---|---|---|---|
| measuredLoadedWheelDiametersInches | Measured loaded wheel diameters inches | list of number | Required |
| frontTeeth | Front teeth | list of number | Required |
| rearTeeth | Rear teeth | list of number | Required |
Enter aligned nonempty positive wheel diameters and integer tooth counts 1–200. Return gear inches per combination.
gearInches=wheelDiameterInches×frontTeeth/rearTeeth Units, indexing, boundary conditions and exceptional cases are defined in the calculation rules above.
| Output field | Meaning | Value type |
|---|---|---|
| gearInchesByCombination | Gear inches by combination | list of number |
{
"input": {
"measuredLoadedWheelDiametersInches": [
26,
28
],
"frontTeeth": [
50,
48
],
"rearTeeth": [
25,
16
]
},
"output": {
"gearInchesByCombination": [
52,
84
]
}
}Limitations and assumptions
No bike-fit recommendation or measured rollout correction is inferred.
Numeric inputs, where present, must be finite. Follow the calculation-specific rules for overflow, underflow and exceptional cases. Numeric lists are limited to 10,000 entries; string lists to 128 strings of at most 128 characters each. The rules above may impose smaller limits. Missing required fields, extra fields, wrong value types and violations of the calculation rules are input errors.
Alternative or Complementary methods
Use Cycling Cadence to Speed Calculator: Cadence and tooth ratio determine ideal wheel rotation. Measured circumference converts that rotation into no-slip ground speed. For a complementary task, use Power-to-Weight Ratio W/kg Calculator: Watts per kilogram normalizes power by rider mass. A total bicycle-and-rider model would require additional mass evidence.
References
-
Gear Inch Bike Calculator — tool.io
Similar or alternative tools
- Cycling Cadence to Speed Calculator
Cadence and tooth ratio determine ideal wheel rotation. Measured circumference converts that rotation into no-slip ground speed.
- Power-to-Weight Ratio W/kg Calculator
Watts per kilogram normalizes power by rider mass. A total bicycle-and-rider model would require additional mass evidence.