The photo is from the 2021 Tour de France. 21 riders were injured in a crash.

I’ve been riding with the club for over 25 years and have seen my share of accidents and dumb behavior. However, this is a safety message in reverse. I’m telling you first what not to do and then offering advice on how to avoid trouble. None of the examples are fictional. All are based on actual incidents, and are listed in no particular order. We hope you will be forewarned and prepared for similar circumstances.

• The group is heading up a hill, and the slower riders slow down considerably. A faster rider moves to pass, but the incline is very steep and he can only pass slowly. Another fast rider tries to pass, but encounters the same difficulty passing quickly. You suddenly have several riders fanned out in a row almost completely blocking the roadway. A car comes from behind, and in a rush to provide clearance the row of riders crashes. When joining a group that is passing slower riders, take notice of how many riders wide that group is, before you join them.
• The roadway has fresh pavement, and the riders are gleeful as they wander along, unaware they are about to cross a town line where the road has not been repaved. There is a large pothole immediately across the town line, and you know the rest of the story. Road conditions can change quickly. You must always be watchful and not lower your guard.
• There was a storm the night before, and twigs and branches are strewn across the pavement. None are very large and the riders become accustomed to the debris, when without warning a twig gets caught in a front wheel, locking it in place, and the rider is thrown over the handlebars. Any debris on the road can be dangerous and should not be ignored.
• A group is crossing a busy street. One cyclist a few riders back hears others call out “clear” and proceeds without looking and is hit by a passing truck. Calling out “clear" is dangerous because road conditions change quickly and riders behind who follow blindly are at risk of serious consequences.
• It is a week after a snowstorm, and the roads are clear, but sand remains on a downhill stretch that curves. A rider tries to take the curve without slowing and goes down as his rear wheel loses grip in the sand. Speed control is essential when there are indications road conditions are changing.
• You spot a dog up ahead seemingly minding its own business. It is not leashed. You approach the dog thinking it will remain in place, but it suddenly darts towards you, and gets caught in your front wheel. Animal behavior is difficult to predict. Always be careful when approaching an unleashed animal.
• The route travels though a built-up neighborhood of single-family homes. There is neither traffic nor street life and you become less wary, unaware a car is backing out of a driveway into your path. A quiet environment can change unexpectedly. Always be on the lookout for moving vehicles.
• The rider is new to GPS navigation, and stares at his cell phone, not aware a pedestrian is crossing the road. It is an elderly woman who suffers serious injury after the crash. Cell phone navigation should only be done with glances at the phone. If you must study the screen, it is best to stop first.
• It rained the night before, and the potholes are filled with water. You pass many that are shallow, and regrettably ignore the one that is deep. Rain-filled potholes are deceptive. It is best to assume they are all several inches deep and avoid any water-filled pothole.
• There is a steep downhill, and you delight in going full speed. Unfortunately, the road curves at the bottom of the hill, and you are traveling too fast to negotiate the turn. On downhill turns it is more difficult to maintain control. Better to slow safely than to be sorry you didn’t.
• There was a short section of a wooden boardwalk still wet from the rain the evening before. The riders slipped and went down hard. Wooden surfaces are slippery when wet.
• A rider pushing to stay with a group moved up close to the next rider’s rear wheel. When the riders at the front of the group suddenly swerved they all crashed. When riding in a group you must signal before you stop, slow down, change direction, or pass.
• The rider was taking a right turn onto a busy road. He looks to his left for oncoming vehicles, but neglected to look right and did not notice the 4-inch pile of sand after the turn. He went down but luck was on his side and he was not hit by oncoming cars. As your Mom told you way back, "look both ways".
• The group pulled off the road to re-group. It was a steep embankment. A rider clipped out and extended her foot to the ground. Due to the slope her foot didn’t reach the ground causing leg injuries. Care is required when getting on/off your bike on sloped or uneven terrain.
• A fast-moving group approaches a side street when at the last minute the lead rider signals a right turn. Not wanting to miss the turn, the following riders try to slow and make the turn. The result is an accordion crash of all the riders. If you approach a turn and sense you can’t slow enough to turn safely, it’s better for you and everyone behind you to continue straight for a bit and come back and make the turn.  

We listed "what to do" in the above situations, but we think safe behavior should be obvious in these circumstances.

Tim Wilson edited this article.