Marine drive system with belt drive

An boat drive system, for propelling a boat through water comprising

• a power input shaft,
• a power output shaft,
• endless loop flexible coupling means for coupling between said shafts, said flexible means having plural legs extending between said shafts, and
• a back bender having a generally smooth surface for bending the path of at least one of said legs toward another of said legs, wherein said at least one leg slides across said smooth surface and said back bender tends to reduce the cross-sectional area profile of the drive system transversely to the direction of travel through the water.

An outdrive for a boat comprising:

• a power input member;
• a power output member which is below the water line when said outdrive is operated;
• an endless loop flexible drive coupling operatively connecting said power input member to said power output member, said drive coupling having legs extending between said members;
• a housing around said legs;
• and
• structure pinching said legs together in said housing adjacent said power output member so as to narrow the cross-sectional profile of said housing below the water line and thereby reduce drag;
• said structure including at least one curved stationary surface that bends the path of travel of one of said legs toward another leg.