KW damping and valve technology, 2-way
KW's adjustable dampening technology is offered for
a wide selection of applications and vehicle class categories.
Damper Basics - The function of a shock absorber
A shock absorbers job is to subside vibrations caused by the wheels, axles, and body. So the technically correct name for it would be a vibration damper. When driving over irregularities, the created shock or vibrations are absorbed by the suspension.
The spring wants to absorb and release stored energy. In a short sequence of these repetitive processes, a vibration arises. These movements are transmitted via the piston rod to the shock absorber. Here the kinetic energy is converted to heat by hydraulic resistance in the shock absorber valve and reduces the vibrations to an inaudible minimum.
- Rocking of the body at successive irregularities
- Gasp or strong immersion during acceleration or braking
- Jumping wheels
- Swerving when braking
- Spinning in corners with a lacking tracking
The shock absorbers used in vehicles are usually twin-tube dampers or mono-tube dampers. A piston moves in an oil-filled cylinder in both damper types. The piston forces the oil through the valves, which creates resistance to the oil flow with the help of various holes and orifices.
During rebound, the oil flows from the outer tube back into the inner tube. In addition to the channels in the bottom valve, the oil also has to flow through the rebound valve located at the piston rod, to get into the piston housing.
How a KW twin-tube shock absorber functions
When a car deflects while driving, the oil which is slightly under pressure, will be displaced by the immersion of the piston rod. It flows into the outer tube through the bottom valve (compression valve) which controls the flow speed.
The damper of a suspension kit converts the kinetic energy of the suspension spring into heat energy and passes it into the environment. While driving a curve in the road, the KW coilover kit functions within the vehicle providing rebound and compression.
Independent adjustable rebound damping
Rebound adjustment by an allen key
Rebound adjustment by attachable adjustment knob, when space allows
Rebound adjustment by integrated adjustment wheel
16 Clicks - Best perfomance and easy adjustment
KW Variant 2 and KW Street Comfort coilover kits provide 16 clicks of rebound adjustment.
Rebound adjustments can be made to reflect more dynamic driving characteristics or complement a change in tire selection like a different set of tires or winter tires.
The Variant 2 coilover provides the user more then just the height adjustability of a coilover it. The adjustable rebound feature allows the user to dial in a more sportier tighter handling characteristic or a more compliant comfortable setting suitable.
Technical details of adjustable rebound damping
Oil flow during "hard" rebound stroke
Bypass orifice with closed adjuster position. Digressive damping characteristic and the maximum achievable rebound damping. Damping is determined by the setup specific preload of the valve spring at the piston.
A firm but not a hard rebound stroke adjustment avoids rolling- and pitching motions.
Oil flow during "soft" rebound stroke
Bypass orifice with open adjuster position allowing for a progressive damping characteristic and ability to achieve minimum possible rebound damping .The bypass oil volume (black arrows) is not available anymore for the spring preloaded valve at the piston and the damping.
A lower rebound damping increases the driving comfort.
Graphic representation of the relation from damper speed (m/s) to damping force (N) when adjusting the rebound damping.
Individually adjustable compression damping
Compression adjustment by an allen key
Compression with four hole adjuster, accessible through an opening
Compression adjustment by use of a integrated adjustment wheel placed at the bottom of the damper
Rebound adjustment by fix integrated adjustment wheel
12-way adjustable compression damping with a denounced click feature
The KW Variant 3 and KW Clubsport coilovers are the ideal system for performance orientated driving enthusiasts who value an a wide range of dampening adjustment for their vehicles.
The adjustable independent rebound and compression damping provides an extensive range of damper tuning. This enables the enthusiast to directly effect the turn-in characteristics, tracking stability, trip grip, and handling at the vehicle's limits.
The patented KW valve technology for independent rebound and compression damping allows the user to customize their KW damper setup.
Technology of compression damping in detail
Graphic representation of the relation from damper speed (m/s) to damping force (N) when adjusting the compression damping.
Oil flow during closed compression damping in the bottom valve
Spring preloaded bypass valve of compression damping in closed state before compression stroke starts
Position of the bypass valve with increasing piston rod velocity
During low piston rod velocity (black arrows), oil is flowing over the bypass valve
The high speed compression damping (white arrows) is generated by the spring preloaded sleeve. The closed compression valve generates a progressive characteristic low-speed compression damping graph
A firmer compression stroke adjustment prevents the vehicle from rolling during cornering
Oil flow during opened compression damping in the bottom valve
Spring preloaded bypass compression valve in open state before compression stroke starts
Position of the bypass valve with increasing piston rod velocity
During slower piston rod velocities (black arrows), oil is flowing over the bypass valve
The high speed compression damping (white arrows) is generated by the spring preloaded sleeve. The opened bypass valve produces a digressive characteristic compression damping graph in Low-Speed ranges
The Low-Speed damping of this technology enables a consistent high speed compression damping. The (safety-relevant) support of the vehicle during the high speed damping range is not influenced with an opened or closed valve.
KW piston rod guiding and sealing package.
Our modular sealing system exceeds OEM standards. It can be opened easily and allows customized adjustments of the valve technology or rod / piston stroke by an aluminium nut
1. High tensile aluminum nut
2. Self-lubricated special NBR sealing
3. Clamping sleeve
4. O-ring made of temperature-resistant viton
5. Guide bushing with bleed hole
6. Special coated DU plain bearing
7. Small increment rebound spacers