Motorcyclists have a vast amount of hand signals they use when riding in a group. Here's what one of those signals means and ...

To signal a stop, the rider extends their left ... parallel to the road, with their palm open and facing down. The arm and hand are kept out in a static position until the rider is ready to ...

This will ensure that the leader doesn't have to ask everyone to stop ... left palm downward to signal other bikers of the group to slow down. Similarly, there's another important hand gesture ...