Kit consisting of two +4" rear shock absorbers, pin/eye connection for Discovery I.
They have a 60 mm reinforced body, 20 mm increased stem, pressurized two-pipe type, which can be revised and adjusted according to your needs.
The shock absorber that makes up the pair, entirely Made in Italy, is built with steel tubes for mechanical use internally lapped and fully galvanized to avoid corrosion.
All components are sintered for maximum calibration control and the seals are in graphite Teflon to improve smoothness and silence.
The shock absorbers are calibrated in compression like the originals to promote comfort, but more braked in rebound to reduce the hopping of the vehicle. This calibration is designed to best adapt to the Italian off-road vehicle and is compatible with any type of set-up; in any case, the desired one can be chosen at the time of order at no extra cost.
The shock absorber can be recalibrated and overhauled in all its parts and in the first year after purchase the recalibration is carried out free of charge according to your needs.
Inside the shock absorber there is a first internal bump stop in extension resistant up to 5000 kg and a second polyurethane limit bump stop that slows down the last 10 mm of stroke to avoid excessive stress on the frame supports; these limit switches can be used as a travel limit for the axle.
ROTHEN oil with a high viscosity index is used which guarantees the maintenance of the calibration up to 200 °C, therefore these shock absorbers are also suitable for heavy use and raids in the desert.
The new version 2021 has the following features:
- Air Dried pressurization to improve calibration constancy even in extreme conditions;
- T.I.G. for maximum resistance and a refined aesthetic;
- double tube in mechanical steel internally lapped, painted with epoxy powders and phosphated to prevent corrosion, the external tube has a diameter of Ø60 mm and a thickness of 2 mm to withstand impacts, in case the body gets dented the shock absorber will continue to function normally;
- steel rod coated in hard chrome CrVI free with tolerance according to EN ISO 286-2
- sintered internal components for maximum wear-free calibration control;
- graphite teflon sealing band to improve suspension smoothness, compared to cast iron bands they are much quieter.
- double bump stop in polyurethane and steel to stop the extension stroke in a controlled way and not to burden the attachments to the frame and bridges;
- SAE5 high quality oil produced by ROTHEN, specially designed for off-road use with a high viscosity index that guarantees regular calibration up to 200 ° C, essential for intense use such as races or raids in the desert;
- double adjustment of rebound and compression settings, both at high and low speeds with preloaded travel reed valves with star springs in compression and helical spring in rebound;
- double seal with o-ring and oil seal with metal base, the high quality of the closure allows not to use the fork protectors that in the long run create accumulation of dirt and damage the shock absorber, any debris that settles on the stem is cleaned by the double lip of the metal oil seal;
- calibration on a 10-speed test bench, from 5 to 500 m/s to have perfect calibration in all conditions.
The overhaul of the HM4X4 shock absorber is guaranteed at a cost of 50.00 euros each.
AIR DRYED pressurization is an innovative two-stage pressurization technique. It allows to pressurize the shock absorber with inert gas, after having created a high vacuum, completely extracting air and humidity from its interior. This allows to minimize the phenomena of oil emulsion and the creation of rust that humidity inevitably creates inside a non-pressurized shock absorber. In addition to making the shock absorber more performing, the Air Dryed pressurization considerably extends the duration of the shock absorber over time and guarantees constant calibration even after years of use.
- fully open length: 630 mm
- stroke: 240 mm
- they are installed on the original attachments without making any changes.