How this calculator works
A time gap is measured as the difference in seconds between two riders passing the same point. To turn it into a distance, multiply the gap by the breakaway speed. The peloton closes that distance at the difference between its speed and the breakaway speed, so the catch time is the distance divided by that difference. The distance the peloton rides before the catch is its speed times the catch time. Dividing the catch time by the number of breakaway riders gives an equal-share pull time if they rotate perfectly.
Formula
Gap distance = breakaway speed x time gap. Closing speed = peloton speed - breakaway speed. Catch time = gap distance / closing speed. Distance ridden by the peloton = peloton speed x catch time. Pull per rider = catch time / riders.
Worked example
A breakaway 60 seconds ahead at 40 km/h is 40,000 / 3600 x 60 = 666.7 m up the road. If the peloton rides at 45 km/h, it closes at 5 km/h, which is 1.389 m/s. The catch takes 666.7 / 1.389 = 480 seconds, or 8 minutes, during which the peloton covers 45,000 / 3600 x 480 = 6,000 m. With five riders sharing the work equally, each would pull for 96 seconds.
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Frequently asked questions
Why is the gap distance not just the time gap?
Time and distance are different things. The same 60-second gap is longer in metres at 50 km/h than at 30 km/h because the breakaway covers more ground in each second.
What if the peloton is slower than the breakaway?
Then the gap grows rather than closes, and the calculation has no catch. The page rejects that input instead of returning a negative time.
Does drafting change the answer?
It changes the speeds the riders can hold, not the kinematics once those speeds are fixed. A chasing group that shares the work can hold a higher speed than the breakaway, which is why the gap often falls quickly near the finish.