gravity limits us because its hard to ride a bike up hill
it depends on how fast you ride or if your gowing up a hill
Same reason as walking up stairs is hard - you have to overcome gravity.
Going up a hill would make your acceleration decrease or cause it to be slow. Going down a hill would make acceleration increase causing you to go faster.
If you ride hard enough to get your breathing and heart rate up - yes.
Passive Transport
3 and up
to roll down the hill on a bike without pedaling is called coast or coasting
11 or up.
No on a cbt you can only ride up to 14.6 bhp to ride a 33bhp bike you must pass you full test .
Food.
A dirt bike can be able to go up a kids slide