'To ride a hobby' definitions:

Definition of 'To ride a hobby'

From: GCIDE

Ride \Ride\, v. t.
1. To sit on, so as to be carried; as, to ride a horse; to ride a bicycle. [1913 Webster]
[They] rend up both rocks and hills, and ride the air In whirlwind. --Milton. [1913 Webster]
2. To manage insolently at will; to domineer over. [1913 Webster]
The nobility could no longer endure to be ridden by bakers, cobblers, and brewers. --Swift. [1913 Webster]
3. To convey, as by riding; to make or do by riding. [1913 Webster]
Tue only men that safe can ride Mine errands on the Scottish side. --Sir W. Scott. [1913 Webster]
4. (Surg.) To overlap (each other); -- said of bones or fractured fragments. [1913 Webster]
To ride a hobby, to have some favorite occupation or subject of talk.
To ride and tie, to take turn with another in labor and rest; -- from the expedient adopted by two persons with one horse, one of whom rides the animal a certain distance, and then ties him for the use of the other, who is coming up on foot. --Fielding.
To ride down. (a) To ride over; to trample down in riding; to overthrow by riding against; as, to ride down an enemy. (b) (Naut.) To bear down, as on a halyard when hoisting a sail.
To ride out (Naut.), to keep safe afloat during (a storm) while riding at anchor or when hove to on the open sea; as, to ride out the gale. [1913 Webster]