Using a screwdriver for leverage, grip the front wheel firmly and pull it up.
You may remove and clean the smaller wheel on Bob's wheel piece. To detach it, grip firmly and pull.
Remove the 2 screws holding the wheel piece together with a Phillips head screwdriver.
Then pop the wheel piece open. After you’ve cleaned the inside of the wheel piece, replace the spring inside.
Insert the straight end of the spring into the square indent and hook the curved end of the spring underneath the tab.
Hold the wheel piece together while you reinstall the 2 screws.
Replace the smaller wheel as well.
Lastly, place the front wheel back in its space on Bob and push down to lock the wheel in place.