It has to do with gravitational pull.
If you're rolling downhill - gravity. If you're going along on the flat - the pedalling effort of the rider.
In the simplest of explanations, they are downshifting. It makes it easier on the legs, as it requires less energy to push the pedals, but also the causes a lower ratio of turns of the pedal to turns of the wheel.
If mud slides downhill, then yes, gravity makes the sliding downhill happen.
Gravity is the primary force that causes objects to move downhill. Objects are pulled downward towards the center of the Earth by gravity, accelerating them as they move downhill.
The basic reason is going to be friction. The brake pads rub against the tire or tire rim to create it.
rephrase... question makes no sense
The salt,cold or sand
The pedals, crank, chain, sprockets, and wheels. Along with the rider, they all work together to make the bicycle go.
In general, using a high gear on a bicycle allows for faster speeds but requires more effort to pedal, while using a low gear makes it easier to pedal but limits your speed. High gears are best for flat terrain and downhill riding, while low gears are ideal for uphill climbs and starting from a stop.
A bicycle consist of several simple machines, which makes it a complex machine.
A compound machineA bicycle consists of several simple machines, which makes it a complex machine.
It's suspension in the forks and or rear of the bike.