May Britt Betty Ramsey Padgett Jenkins Burch Messier Brittany Ramsey General Assembly Britt Hampshire www.enaos.net. Carrying on a tradition of durability and dependability, Clevite BiMetal (aluminum) engine bearings feature 100% lead free aluminum silicon. Engineered with 60% more silicon than comparable competitive replacements, they provide better conditioning of journal surfaces. This results in greater seizure and wear resistance.