If you are riding behind another vehicle at night, you can determine if there are bumps on the road ahead by:

To determine upcoming road conditions when riding at night, use the vehicle ahead of you. For example, the headlights of the vehicle may provide a better view of the road than your own high beam. If the vehicle's taillights bounce up and down, this indicates the presence of bumps on the road.

• Listening for the other vehicle scraping against the pavement.
• Noticing the other vehicle’s taillights bouncing up and down.
• Looking at the rear bumper of the vehicle ahead and trying to determine if it is bouncing.