When a track setup feels “too big” or “too small,” write down the chainring, sprocket, tyre rollout, and cadence you want to examine. Then compare one change at a time.
What the calculation does
For a fixed gear, rollout is the distance travelled by one wheel revolution. Gear ratio is chainring teeth divided by sprocket teeth. At a chosen cadence, estimated speed follows from rollout × ratio × cadence. Those are relationships, not predictions of what a rider will hold in a race.
The Gear Matrix calculates gear inches, rollout, estimated speed, and cadence from the inputs provided. It does not measure tyre rollout, power, air density, or an actual lap.
Source: 3UpLabs calculator behavior, checked 2026-08-18.Use a baseline, not a verdict
Pick a familiar setup and record the inputs. Change the chainring or sprocket, then inspect what changes at the same cadence. A calculated comparison can guide a training test; it is not evidence that the setup will produce a faster time.
Track events, rider position, tyre choice, surface, pacing, and competition all affect the outcome. This note makes no legality, performance, or rider-specific recommendation.
Basis: workshop interpretation and boundary statement.What to record at the track
- Gear and tyre setup, with rollout assumption.
- Target cadence or speed and session distance.
- Actual lap or split times, conditions, and how the gear felt.
- One change for the next test.
A calculator makes the comparison legible. Only a measured session can tell you what happened on your bike, with your position, on that day.