In the world of recreational bicycling, communication is vital. Other cyclists and motorists cannot use mental telepathy to anticipate a rider's intentions. Instead, bicyclists must rely on a uniform code of hand signals to communicate turns, stops and reversals. Failure to use proper hand signals can result in collisions among riders and accidents with motorists sharing the road.
One of the most vital hand signals is the stop command. If the leader of a cycling pack decides to stop suddenly, the remaining riders may not have sufficient time to avoid a pile-up. The stop signal is performed by extending the left arm slightly away from the body and pointing the palm towards the back. The rider should maintain control with the other hand and only stop the hand signals to apply the brake.
Some bicyclists may anticipate the stop signal with one that means slow down or caution. This hand signal is performed by extending the left arm straight out from the body and bending it from the elbow at a downward 90º angle. It should look like an upside-down L. From this position, it should be easy for the cyclist to drop into the full stop hand signal when necessary. Caution hand signals can alert other riders to potential road hazards without the need for a full stop.
Other important hand signals involve turning and other changes in direction. A right turn is indicated by extending the left arm straight out, much like the caution signal, but with the lower arm bent at an upward 90º angle. It should look like the rider is forming an L. Again, control should be maintained with the other hand and the signal should be removed just before committing the actual turn.
A left turn is indicated by extending the left arm straight from the body without bending it. In essence, the rider is pointing towards the direction he intends to turn. Since a left turn, or right turn in some countries, may involve crossing against traffic, great care should be exercised when executing it. Some cyclists may encounter trouble if they fail to maintain their hand signals long enough or use ambiguous hand positions. All hand signals should be performed in a deliberate and definite manner to avoid any confusion among fellow riders or motorists.