Motorcycle Braking Distance
Reaction and braking distance by speed and surface, how much speed you still carry if the road runs out, and what a following gap really covers.
If you run out of road
The last part of a stop sheds the least speed
Speed does not fall evenly across the braking distance, and the direction surprises people. Because energy goes as the square of speed, halfway through the braking distance you are still doing 71% of your original speed, and three quarters of the way through you are still doing 50%.
Read that the other way and it is worse: getting from 60 to 30 mph eats three quarters of your braking distance. So being twenty feet short of a stop is not "nearly stopped" — a substantial fraction of your speed is still there when you arrive.
Following distance
The two-second rule assumes whatever is in front brakes no harder than you can. A car with four contact patches and modern stability control frequently out-brakes a motorcycle, and a stationary object out-brakes everything — which is why a fixed time gap covers a progressively smaller share of your actual stopping distance as speed rises.
Distance by speed on this surface
| Speed | Reaction | Braking | Total | vs 30 mph |
|---|
Things worth knowing
- Braking distance goes as the SQUARE of speed. Doubling your speed quadruples it, which is why 30 to 60 mph feels like twice as fast and stops like four times as far.
- Reaction distance is linear, so at 20 mph most of your stopping distance is reaction time and at 80 mph very little of it is. Practising the brake helps at speed; leaving space helps everywhere.
- The two-second rule assumes the vehicle in front brakes no harder than you can. A car with four contact patches and modern stability control frequently out-brakes a motorcycle, and a stationary object out-brakes everything.
- Most riders never use the front brake properly because they have never practised it. The front does the large majority of the work on tarmac, and the only way to learn how much is to go and find out somewhere safe.
- The first ten minutes of rain are the worst of it, as oil and rubber lift off the surface before the water has washed them away.
These are physics figures for an idealised stop at a given grip level. A real emergency stop on a real bike is worse — grip is not uniform, weight transfer takes time, and almost nobody reaches the tire's limit without having practised.
How to use
- Set your speed, the surface, your reaction time and any grade.
- Read the split between reacting and braking, with speed marked along the stop.
- Use the road-available slider to see what speed you would still be carrying.
Frequently asked questions
How far does a motorcycle take to stop from 60 mph?
About 150 feet of pure braking on dry asphalt with good tires and a practised rider, and around 190 for an ordinary rider on an ordinary bike. Add reaction distance on top — at 1.5 seconds that is another 132 feet before the brakes do anything.
Why does speed matter so much?
Braking distance goes as the square of speed, so doubling your speed quadruples the distance. Thirty to sixty feels like twice as fast and stops like four times as far.
How much of stopping distance is reaction time?
About 70 per cent at 20 mph and still more than a third at 80. It falls as a share because the braking term is squared, but it never becomes small enough to ignore.
If I almost stop in time, is that most of the benefit?
No. Halfway through the braking distance you are still doing 71 per cent of your speed, and three quarters of the way through you are still doing 50. Getting from 60 to 30 uses three quarters of the braking distance on its own.
Is the two-second rule enough on a bike?
It assumes whatever is in front brakes no harder than you can. A car with four contact patches and modern stability control frequently out-brakes a motorcycle, and a stationary object out-brakes everything — so a fixed time gap covers less of your stopping distance the faster you go.
How much worse is wet?
About 40 per cent further than typical dry. Wet leaves are four to five times worse, and ice is nine times — with the added problem that wet leaves look nothing like ice while behaving very like it.
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