Roadworthiness
Bikes vary in their ability to corner, and they only corner to the best of their ability, if they are well maintained. Steering, suspension, tires, tire pressure and loading of the bike will affect its balance and road grip when cornering.
Cornering and balance
The front wheel of a motorcycle is only turned significantly to change direction at very low speeds. The bike and rider remain virtually upright and the demands on tire grip are minimal.
At higher speeds the rider needs to lean into the bend to counterbalance the perceived effect of body and bike flying outwards.
The sharper the bend or the higher the speed, the greater the required degree of lean to maintain balance.
Camber and super elevation
The road surface is not normally level across its width but is built with a slope to assist drainage. The slope across the road affects steering. The normal slope falls from the crown of the road to the edges and is called camber.
On a left-hand curve, camber assists cornering because the road slopes down in the direction of the turn, and reduces the angle between the tire and the road surface – increasing the area of contact between the tire and road.
On a right-hand curve, camber reduces the stability of cornering because the road slopes away from the direction of turn, and increases the angle between the tire and the road surface – reducing the area of contact between tire and road.
This applies to normal camber only if you keep to your own side of the road.
Super elevation is where the whole width of the road is banked up towards the outside edge of the bend, making the slope favorable for cornering in both directions.
To sum up, the factors that determine your bike’s ability to corner are:
- speed
- amount of lean you apply
- amount of acceleration or braking
- slope across the road surface – camber and super elevation
- road surface conditions
- characteristics of the bike and its ground clearance
- weight and distribution of load carried
- rider’s ability
