What is the difference between these two examples?
I go on a ride.
I go for a ride.
Go on a ride suggests having a thrilling experience at a theme park. Go for a ride suggests an excursion on a bicycle, a motor cycle or a horse.
You would normally use the present tense, I go, if you followed it with a time expression such as ‘I go for a ride every Thursday.’ If you’re describing what you are about to do now, you use the present progressive construction: 'I am going for a ride'.
Intuitively, 'go on a ride' seems to imply passive partaking in said ride, while 'go for a ride' implies an active decision and a certain level of control.
You would go on a rollercoaster ride, but go for a ride on your bicycle. Note that a ride-along is also something you go on, as you're not behind the wheel.
For a ride: Partake in a leisurely journey in a car with the person who asked you to "go for a ride." For example, my father would say "let's go for a ride," on Sundays and we all knew we would sit in the passenger seats of a car as he drove us around our city to relax with the car windows rolled down, people watch, and enjoy the view of buildings we passed.
On a ride: The term "ride" in this phrase means some locamotive that was created to provide enjoyment. The ride can be a variety of things from a hay-rack ride at a pumpkin patch, rollercoaster or any other fun driven "ride" at an amusement park for example. The word "on" in this particular phrase is most important and tells you the goal is amusement.