Velocity and Acceleration -- use a
Bike Computer/Speedometer: Through experience, I have found 15-17
mph (24 - 27 kph) to be the safest maximum cruising speed for
a commuting/touring bike. Going faster increases the risk of losing control
over the bicycle if the need for a quick, accident-avoiding maneuver --
such as braking -- arises.
Above: Handlebar-mounted bicycle computer (this
one is the CatEye Astrale 8). Its mounting position was angled for best
visibility. There are two buttons that let you program the unit or toggle
between several modes and displays.
Remember: the relationship between speed and stopping distance is not linear -- it's exponential. For example, if adhesion coefficient (0.85) and rolling coefficient (0.014) are held constant, here are some traveling speeds and their respective stopping distances:
15 mph --- 8.53 ft (or 2.6 m)
17 mph --- 10.96 ft (or 3.34 m)
20 mph --- 15.17 ft (or 4.62 m)
As can be seen, increasing speed by only five miles per hour effectively almost doubles stopping distance!
Use the speed-vs.-stopping-distance calculator here to see more examples.
It's far too easy to underestimate velocity, so be aware of acceleration during tricky down-grades. The use of a speedometer (often built into modern cycle computers) an help train you to get the "feel" for the speed at which you are traveling. top of page
Most bike bells are mechanical and are not loud enough to penetrate traffic noise. They work well on bike paths, but use them sparingly. A politely-toned "pardon me" or "on your left" works better in most cases.
Above: A mechanical bike bell. Usually, it's best
to mount this next to the hand grips on the handlebar. I mounted it on
the handlebar stem because I ran out of room on the handle bar!
A new product from Delta is a 115db Airhorn. It works by pumping air into a mini tank with a tire pump. The tanks installs in the water bottle cage (here's an image of the horn and of the tank). I have no experience with this product. It costs about $20. See the vendor link on our References and Resources page for more information. top of page
First-Aid Kit: If you take a spill, it's important to disinfect cuts as soon as possible. Always carry a small, portable kit with you. There are many, ready-to-use kits available (such as the one in the image below) and they tend to be cheaper and more comprehensive than virtually any homemade version you can come up with. I also put some NeoSporin and extra Band-Aids into the pre-packaged kit. top of page
Above: A small, portable
first aid kit and NeoSporin: Essential carry-alongs for commuting and
touring.
Water bottle: Take water with you and drink it regularly, even if you're not thirsty. It will keep you comfortable and thinking clearly (which is very important for sense-of- judgment decisions and, hence, riding safety). top of page
Cellular (Mobile) Phone: Let's face it: a cell phone is an important utility of the modern world. And it can come in quite handy in an emergency: say you are in a rural area, took a spill, and are injured serious enough to prevent you from walking for help. Please note: you are subject to the same laws and regulations as motor vehicle operators. Your local jurisdictions may curtail motorist/bike-based cell phone use even further. If you must use the phone, pull off the road and talk. If you must talk and ride, do so sparingly and use hands-free cellular accessories. top of page
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Guide to Bicycle Safety: [Part 1 | Part 2 | Part 3 | Part 4 | Part 5 | Part 6 | Part 7]