Tag Archives: Front Suspension

Wheelbase

Pin It

‘Wheelbase’ is the distance between the centre of the front axle and the centre of the rear axle. Wheelbase length has a big influence on the axle load distribution. Longer wheelbase : Less load transfers between the front and rear axles…

Pin It

Trail / Caster Offset

Pin It

The distance from the ‘Steering Axis’ to the centre of the tyres’ footprint on the ground is called ‘Trail’ or ‘Caster Offset’. The larger the trail, the more steering torque is needed. Under acceleration or braking Trail can be broken…

Pin It

Track Width

Pin It

‘Track Width’ is the distance between the center line of each of the two tyre contact patches on the same axle. It is not the distance between the wheel mounting flanges. On most vehicles, the track width will differ between the front and…

Pin It

Toe In / Toe Out

Pin It

The amount of toe is expressed in degrees, as the angle from parallel of the front wheels. Sometimes Toe is expressed as the difference between the track widths of the leading and trailing edges of the front wheels. Toe adjustment…

Pin It

Steer Camber

Pin It

‘Steer Camber’ is a product of ‘Steering Axis Inclination’. It is a small amount but not to be neglected if tight high speed turns are an issue. ‘Caster Angle’ will provide beneficial camber changes as the wheels steer. With positive caster…

Pin It

Steering Axis Offset

Pin It

In side view, if the ‘Steering Axis’ doesn’t pass through the centre of the wheel, there is a ‘Steering Axis Offset’. This is sometimes referred to as ‘Kingpin Offset’.

Pin It

Steering Axis Inclination

Pin It

Steering Axis Inclination (SAI) is also known as King Pin Inclination (KPI). The ‘Steering Axis’ is the axis around which the wheel assembly swivels as it turns to the right or left. It’s formed by drawing a line through the upper…

Pin It

Scrub Radius

Pin It

The scrub radius is the distance in front view between the Steering Axis and the centre of the tyre contact patch where both would theoretically touch the road. The “steering axis” is the line between the top pivot point of…

Pin It

Scrub

Pin It

As a wheel travels up and down with relation to the chassis, the track width of the car changes. This change is known as ‘Scrub’. It is important not to get ‘Scrub’ and ‘Scrub Radius’ confused. As the name implies…

Pin It

Roll Centre

Pin It

A line is projected from the ground contact patch, at the contact point of the Steering Axis Inclination, through the wanted Roll Centre and to the Instant Roll Centre located at the desired Swing Arm Radius (fvsa) length distance from…

Pin It