Bosch ABS M4, User Manual, Page: 23 / 54

Brake Lines
Use rigid steel brake lines for as much of the plumbing as possible. Flexible line
should be kept to an absolute minimum for optimal ABS control and pedal feel.
The hydraulic unit is secured in the vehicle on the provided mounting plate. Dur‐
ing operation, the hydraulic unit will vibrate. These vibrations are then transfer‐
red to the brake lines. To prevent vibration‐induced damage to the brake lines,
they must not be secured at a distance of up to 20 cm from the hydraulic unit so
that they can vibrate freely.
Notice
We recommend using rigid metal brake lines; use flexible lines
only at points where they are necessary.
Do not secure brake lines 0 to 20 cm from the hydraulic unit.
The unit vibrates and would cause risk of damage to the lines.
Please use brake lines with a minimum inside diameter of 3.2
mm.
General: Brake Calipers
Use brake calipers that are as stiff as possible. Any flex in the brake caliper causes
extra fluid volume that must be regulated by the ABS, which reduces perform‐
ance.
During ABS operation there will be a significantly higher load on the brake piston
seals. For this reason, brake piston seals will require more frequent monitoring.
Notice
Monitor brake piston seals more often.
Use brake calipers that are as stiff as possible.
The higher the brake pressure is, the larger is the elasticity of the brake. A locking
pressure of max. 80 bar is optimal.
7.11
7.12
Assembling the Parts | 7
Bosch Motorsport ABS M4 Manual 23 / 54