4Terrain Ultimate, More Than a Heavy-Duty Clutch

4T Ultimate with Patented* ER² Groove Design has several features which make the product distinctly new. It is comprised of a cover assembly, clutch disc and release bearing (Some kits also include a solid replacement flywheel or DMR).

The cover assembly incorporates a premium corrosion resistant surface finish, which exhibits excellent resistance to oxidation over a prolonged period of time. In addition the clutch pressure plate incorporates 4T Ultimate’s exclusive ER2 design technology.

The cover assembly’s pressure plate is manufactured from Spheroidal Graphite casting material and has a yield strength some 300% higher than standard castings. The materials microstructure also improves heat dispersion. The cover assembly incorporates greater clamp load than a standard cover assembly. This translates to more torque capacity.

The kit’s clutch disc has a unique flywheel side friction material. The Aramid friction material exhibits 50% less wear than a conventional clutch disc’s friction material. This material also reduces the effects of clutch fade. Fade is the decline in the clutch system’s ability to transmit torque as operating temperatures increase.

These features in combination with the previously mentioned microstructure of spheroidal graphite casting and ER² Technology allows the clutch kit to dissipate heat far more effectively, allowing the clutch to run cooler for longer.

It also means that the clutch system is capable of transmitting greater than 60% more torque than a standard Clutch Kit making it suitable for demanding conditions. This overall Torque Capacity increase has been achieved by higher Clamp Loads, increased Mean Effective Radius of the pressure plate, better cooling and higher coefficient of friction materials on the Clutch disc.

The Patented* pressure plate with ER² grooves are precision machined with CAD/CAM technology. The design enhances the performance in 2 ways. Firstly it increases the torque capacity of the cover assembly and secondly it assists with cooling which in-turn enables the friction material to operate at lower temperatures and therefore at a higher coefficient of friction. Again this enhances the torque capacity of the clutch.

Get Into The Groove with ER² Clutch Cover Assemblies



4Terrain Ultimate Cover Assemblies with the Patented* ER2 Groove Design features a unique groove pattern which is CNC machined on the friction face of the pressure plate.

This groove has been specifically designed to increase the Mean Effective Radius of the pressure plate and assist in heat removal. The increase in the Mean Effective Radius of the cover assembly gives a significant increase in torque capacity.

By adding the groove to the pressure plate, the inside radius of the friction face has effectively been increased. The first 8mm of the pressure plate has all but been removed and added to this, there is progressively less material removed as the radius increases. The net effect of this is to move the effective inside radius further out.

When comparing the Mean Effective Radius (Rm) of the ER2 version to the non ER2 version you can see the ER2 version is further out. This increases the torque capacity of the clutch. Torque capacity is directly related to Rm.