Bike TT predictor · live demo
Sign up to run it on your real lactate test →Pick an engine or drag the sliders. The optimal pacing plan and its honest finish window recompute live from the physics, no account needed.
Start from an engine
FTP / CP300 W
W′, surge battery22 kJ
The extra energy you can burn above FTP on climbs and attacks before blowing up; it recharges when you back off.
System mass72 kg
CdA, aerodynamic drag0.24 m²
Durability, fade per 1000 kJ2%
How fast your engine fades on long rides, on top of the normal duration slowdown already modelled. A durability test refines it.
Distance40 km
Elevation gain300 m
Descent roughly matches the climbing, like a real road race.
Computing your pacing plan…