Hand signals are given by cyclists and some motorists to indicate their intentions to other traffic. Under the terms of the Vienna Convention on Traffic, bicycles are considered to be vehicles and cyclists are considered to be drivers. The traffic codes of most countries reflect this. In some countries, hand signals are designated not only for cyclists, but for every vehicle that does not have signal lights or has damaged signal lights. For example, drivers of older cars and mopeds may be required to make hand signals. Similar to automobile signaling, there are three primary signals: Left turn/overtaking, Right turn, and Stopping/braking.
Left turn
The same signals are also used for overtaking to the left in Right-hand traffic countries. ; All Countries : Extend left arm straight out in the direction of the turn, horizontally. ; South Africa : The driver extends his/her right arm with the forearm pointing vertically downwards and moving in a circular anti-clockwise motion. For tractors, animal-drawn vehicles and two-wheeled vehicles, the driver is allowed to extend their left arm horizontally with the palm to the front. If a vehicle is fitted with turn indicators, they may be used instead.
Right turn
The same signals are also used for overtaking to the right in Left-hand traffic countries. ; US and Canada, : Current convention for signaling right, either while cycling in traffic or cycling with other riders, is to extend the right arm perpendicularly to the body; to wit, the cyclist arm is pointing in the same direction of the intended turn. Prior to the common sense approach of extending right arm to indicate a right turn, the convention was for cyclist to extend the left upper-arm out to the left, horizontally and angle one's forearm vertically upward; this practice is no longer in use due to safety concerns. The Uniform Vehicle Code in the US recognizes both signals; although, the Code strongly encourages cyclists to use the arm to the right technique. State traffic laws generally conform to the Uniform Vehicle Code, but exceptions may exist. British Columbia recognizes both. ; South Africa : The driver extends their right arm horizontally with the palm to the front. If a vehicle is fitted with turn indicators, they may be used instead. Arm to the right has the advantage that it is more visible to any traffic likely to be affected, for example vehicles in the next lane to the right or also intending to turn right. It is also easier to teach to children: "point in the direction you are going to turn."
Slowing down
; South Africa : Sudden reduction in speed requires the same signal as stopping. It is also allowed to extend the right arm horizontally with the palm facing down and move the arm upwards and downwards.
Overtaking
; South Africa : A vehicle may signal a vehicle behind them to overtake them by extending the right arm below shoulder level, with the palm facing forwards, and moving the arm forwards and backwards.
Stopping/braking
; UK and Ireland : To indicate that you’re about to slow, extend your right arm fully out to the side, palm-down, and move your hand up and down at the wrist. To indicate coming to a full stop, extend your right arm vertically, with palm facing forward. ; US and Canada : Extend your left arm out to the left, horizontally and angle your forearm vertically downward. ;Italy : Extend your right arm vertically, with palm facing forward. ; Australia, Denmark: Extend your right arm vertically, with palm facing forward, or extend your right upper arm out to the right horizontally and make your forearm vertical with your palm facing forward. ; South Africa: Extend the right upper arm out to the right horizontally and make your forearm vertical with your palm facing forward.
Conflict with brake operation
A bicycle's front brake lever is typically installed on the side of the handlebar closest to the center of the road. In many countries, the hand signal for stopping/braking requires that the cyclist signal with the hand used for the front brake. The front brake is the most effective method of stopping a bike under normal road conditions. Cyclists, like all other road users, should be ready to make an emergency stop at all times. When approaching a junction a cyclist may wish to "cover the brake" in readiness for an emergency stop. It is not possible to cover both brakes when performing a hand signal and both hands are needed on the handlebars to steady the bicycle under hard braking. Cyclists therefore sometimes have to choose between giving a hand signal and covering the brake.
