Obviously, braking dynamics change on hills. Braking heading uphill is easy, because gravity helps slow the bike, and because the weight bias is moved toward the rear. However, braking heading downhill is more difficult, because the downslope pull of gravity adds to the forward energy, while the weight bias is moved toward the front wheel.
The downslope pull of gravity is a constant, depending on the grade. However, downslope gravity is added to forward energy, and kinetic energy increases dramatically with increasing speed
When riding downhill, it’s important to keep speed under control, especially on a curvy road. Engine braking is less effective descending a steep grade because traction on the rear tire can be severely reduced. Approaching a downhill curve, brake early while still in the straight, to avoid having to brake hard while leaning the bike. Downhill left turns are hazardous because
the pavement often cambers to the right, reducing traction and leanover clearance. Even in a downhill right turn, it may be necessary to trail brake all the way around the curve to keep speed from increasing.
In downhill turns, trail braking on the front will help keep speed from increasing, and also make steering lighter.
As front suspension is compressed during braking, the steering axis steepens, with the result that steering trail is reduced, making steering lighter. That means less steering effort is needed to get the bike turned. However, when braking into curves, it is essential to be very smooth when easing on or easing off the front brake, to avoid sudden changes in traction.
The downslope pull of gravity is a constant, depending on the grade. However, downslope gravity is added to forward energy, and kinetic energy increases dramatically with increasing speed
When riding downhill, it’s important to keep speed under control, especially on a curvy road. Engine braking is less effective descending a steep grade because traction on the rear tire can be severely reduced. Approaching a downhill curve, brake early while still in the straight, to avoid having to brake hard while leaning the bike. Downhill left turns are hazardous because
the pavement often cambers to the right, reducing traction and leanover clearance. Even in a downhill right turn, it may be necessary to trail brake all the way around the curve to keep speed from increasing.
In downhill turns, trail braking on the front will help keep speed from increasing, and also make steering lighter.
As front suspension is compressed during braking, the steering axis steepens, with the result that steering trail is reduced, making steering lighter. That means less steering effort is needed to get the bike turned. However, when braking into curves, it is essential to be very smooth when easing on or easing off the front brake, to avoid sudden changes in traction.