B61C9/00—Locomotives or motor railcars characterised by the type of transmission system used; Transmission systems specially adapted for locomotives or motor railcars
B61C9/08—Transmission systems in or for locomotives or motor railcars with IC reciprocating piston engines
B61C9/10—Transmission systems in or for locomotives or motor railcars with IC reciprocating piston engines mechanical
B61C9/12—Transmission systems in or for locomotives or motor railcars with IC reciprocating piston engines mechanical with change-speed gearing