Roller rockers are infinitely stronger than standard steel rocker arms and are more resistant to bending and breakage under high spring pressures at high rpm. Standard pressed steel rocker arms are prone to failure in high performance applications. A high rate of fulcrum wear, flexing, cracking, splitting and breakage are common problems that will result in power loss or possible piston failure due to detonation of the incoming air/fuel charge. The traditional metal tip on standard rockers literally drags across the valve tip as the rocker opens and closes causing high side loading on the valve. This inside force leads to irregular and rapid valve, valve guide, and valve seat wear in many engines. The roller tip on roller rockers eliminates this side loading action.
The use of needle roller bearings at the rocker fulcrum combined with a roller tip at the valve greatly reduces horsepower robbing friction in the valve train to provide a measurable power increase over standard rocker systems. The reduction in friction with roller rockers has additional benefits of reducing the operating temperature and foaming effect of engine oil to provide a cooler running engine.
Unlike standard steel rockers, roller rockers maintain a constant indicated rocker arm ratio throughout the full valve lift because the centre line of the roller stays constant and only its contact with the valve stem center line changes.