S&S Cycle SS31-6200 Oil Pump w/Universal Cover Polished for Big Twin 36-72Fitment: 1936 '69 HD big twin Features& Benefits: Same width oil supply and return gears as the stock HD aluminum pump. S&S pinion and oil pump drive shaft drive gears increase potential oil volume delivery by 25% over stock on 1972 and earlier engines. S&S pumps for 1936 '67 engines used with the S&S oil pump drive gears deliver 33% more oil than the original cast iron pump. Machined with an oil pressure relief bleed off passageway relieves pressure