What action should you take before changing lanes on a dual carriageway?

Explanation: Before changing direction, as well as using your mirrors, you may need to take a quick sideways glance to check for vehicles in your blind spots. These are the areas behind and to the side of you that aren't covered by your mirrors.

Category: Rules of the road (Motorcycle Theory 2021)

References: The Official DVSA Guide to Riding: Section 8