Primary Chaincase Lubricant is specifically designed for the primary chaincase of all Big Twin model motorcycles equipped with a wet diaphragm spring clutch from 1984 to present. It delivers all-weather clutch performance while providing maximum wear protection for the primary chain and cog set. For the primary chaincase of all Big Twin model motorcycles equipped with a wet diaphragm spring clutch from 1984 to present. May be used in chaincases equipped with original, modified or aftermarket high performance clutch assemblies. Especially recommended for modified engines and operation in both especially cold and hot weather climates. Improved clutch performance - Provides smooth, positive clutch hook-up without slipping or shudder in all service conditions from around-town cruising to aggressive drag race launches.