Is bus travel to a synagogue on shabbat permissable if, 1) the jewish public does not see you. 2) one does not ring the bell to get off the bus 3) one only exists from front of bus 4) one has a monthly bus card pined to a jacket

With the exception of “pikuach nefesh”, there are no circumstances in which bus travel is permitted on shabbat. The bus stops for you to get on and off on shabbat; the driver opens and closes the door for your entrance and exit. Even riding the subway or a city transit rail line which stops at every stop whether or not there are passengers is forbidden by Shu”t Chelkat Yaakov Orach Chayyim144 9, Shu”t Sridei Aish I 38, Shu”t Tzitz Eliezer I 21 and others.