EBC - CSK Clutch Spring Set (CSK910)Always fit new springs which get tired after miles of heat and use. EBC spring kits are 10% stiffer than standard and are sold in engine sets. As stated in general fitting safety instructions, advise customers that lever will feel slightly heavier when uprating springs, and to test ride acquaint themselves with this change in control. Please note: We can only supply coil springs diaphragm types are not available other than OEM supply.