Examples
Examples
Try the starting example
- Bottom-bracket axle height above flat ground (mm)
- 300
- Crank centre-to-centre length (mm)
- 170
- Pedal underside below its axle (mm)
- 10
- Crank angle away from straight down (degrees)
- 60
- Pedal-axle height at entered angle (mm)
- 215
- Pedal underside height at entered angle (mm)
- 205
- Lowest underside height over one upright revolution (mm)
- 120
- Rise above lowest underside position (mm)
- 85
Try another scenario
- Bottom-bracket axle height above flat ground (mm)
- 300
- Crank centre-to-centre length (mm)
- 170
- Pedal underside below its axle (mm)
- 10
- Crank angle away from straight down (degrees)
- 90
- Pedal-axle height at entered angle (mm)
- 300
- Pedal underside height at entered angle (mm)
- 290
- Lowest underside height over one upright revolution (mm)
- 120
- Rise above lowest underside position (mm)
- 170
Calculation method
Calculation method
Pedal-axle height at entered angle (mm)
BB height−crank length×cos(angle).
Pedal underside height at entered angle (mm)
Pedal-axle height−entered pedal underside offset.
Lowest underside height over one upright revolution (mm)
BB height−crank length−pedal offset.
Rise above lowest underside position (mm)
Entered-angle underside height−lowest underside height.
Symbols and units
- a
- Bottom-bracket axle height above flat ground (mm)
- b
- Crank centre-to-centre length (mm)
- c
- Pedal underside below its axle (mm)
- d
- Crank angle away from straight down (degrees)
Use the units shown. A list keeps the order in which you enter its values. The symbol ^ means “raised to the power of”.
Assumptions & limits
Assumptions & limits
- Upright rigid geometry over flat ground. Negative heights expose overlap in the inputs. Lean, suspension movement, pedal rotation, terrain and riding clearance are outside this model.
Are these inputs private?
These calculations run in your browser. A shared link contains the values you choose to share. Only questions submitted to the separate AI finder are sent to OpenAI.
Further reading
OpenStax: Euclidean geometry and trigonometric identities ↗
Background reading; this does not imply endorsement or independent review of SumFizz.