HazardsBrake fade
เบรกเฟด
The lever comes back further each time, and then it comes back to the bar.
What it is
Dragging a brake down a long descent heats it until it stops converting speed into heat as well as it did. On a small automatic with a drum rear, this is the failure mode of this road.
The long version
The descents here are not short. Route 1095 drops off a ridge into the Pai valley over kilometres, not hundreds of metres, and the curve density means the brake is being used the whole way.
Inference — the rider who is in trouble is the one who found a speed that felt controlled at the top and held it by dragging. The brake gets hot, the lever travel grows, and because it grows gradually the rider compensates without noticing until there is no travel left. A drum brake filled with hot gas and glazed lining is the version of this that arrives fastest.
What prevents it is not stronger braking. It is engine braking and stopping. Down a gear (or, on an automatic, down to a speed the engine can hold), brake in firm short applications rather than a constant drag, and pull over every few kilometres on a long descent for two minutes. A brake that has faded comes back when it cools; one that has boiled its fluid may not.
What it asks of you
| Smallest sensible bike | Semi-automatic or manual underbone, 110–150cc |
|---|---|
| Difficulty | You have ridden hills before |
| Pillion | Think about it |
A pillion roughly doubles the energy the brakes have to absorb on the same hill.
Luggage has the same effect as a pillion and gives no warning noises.
Runs with
- bikeThe 110–125 step-through — The bike this happens to.
- termEngine braking — The thing that stops it happening.
- roadRoute 1095 — The descent it happens on.
- legThe 1263 cut — The steeper one, with fewer places to pull over.
Named here by
- legChiang Mai to Pai — The descent into Pai is where this happens.
- legThe Samoeng warm-up — Better discovered here.
- legSoppong to Mae Hong Son — The long descent.
- legThe 1263 cut — The descent that produces it.
- roadRoute 1095 — What the descents do to a small bike.
- bikeThe 110–125 step-through — The specific way this bike fails on a long descent.
- bikeThe underbone with gears — What it protects you from.
- termEngine braking — What it prevents.
- storyEvery bike goes up there — The failure mode the whole comparison turns on.
Where each claim comes from
| Field | Tier | Source | Note |
|---|---|---|---|
| default | inference | the mechanism is general motorcycle knowledge; the application to these specific descents is this project reasoning from the measured gradient and curve density | |
| text_th | inference | written in Thai by this project, not machine-translated |
Sources
- Motorcycle safety — Wikipedia (en)
- Curve and distance measurements off the OSM polyline — This project
cited Cited — a named source, linked · harvested Harvested — fetched from an open dataset, with its licence · tradition Tradition — general knowledge of the tradition, hedged · inference Inference — this project's own reasoning from the above · field Field — someone stood there