The recent introduction to the bike profile allows you to change the active profile or bike during a ride in a similar way to how you can change the route during a ride.
To Edit an ongoing ride
Step 1: Press the D button (top right button) to bring in the menu slider.
Step 2: Ride information shows up with selected Profile, Route and Bike.
Step 3. Here you can edit the ride such as change the profile, remove the route, change the bike.
Step 4: Tap on the icon to remove the selected route if you do not wish to ride with a route.
Step 5: Tap on the yellow bar that says "Return to ride" to apply the changes.