Originally Posted by canklecat
Doesn't matter. Cars can't hear any bicycle bell. Nor can most pedestrians, joggers or cyclists wearing earbuds. For those you need an AirZound or similarly obnoxious blaster.
For MUP users who haven't blocked out ambient sounds try a Timber
mountain bike trail bell. It can be set to ring continuously or not at all.
I was curious about the Timber and similar mini-cowbells sold on Amazon and elsewhere. So I rigged up my own from some winter holiday jingle bells, ranging in size from golf balls to slightly larger. I used those on one bike for a couple of months until the thin strap wore out and broke a couple of weeks ago. The jingle bells clinked and clanked continuously while riding, varying depending on how smooth or rough the terrain was. If the bells didn't jingle enough while approaching someone from behind on smooth pavement I'd smack the bells with one hand.
The continuous jingling was remarkably effective yet friendly sounding on the MUP. People who hadn't plugged up their ears would notice and turn to look as I was approaching, and usually smiled. I always slow down and pass as courteously as possible anyway. On the gravel trail it jingled continuously and most joggers/walkers would moved rightward without being prompted. There were still a few who'd remain in the center of the path or go the "wrong" way, but they usually remained consistent in direction rather than wandering around aimlessly.
On one occasion a couple of joggers were two abreast on the narrow paved MUP. The jogger to farthest right heard me and tugged the sleeve of her friend who was blocking the path. As I passed the path-hogging jogger muttered "I heard something jingling but didn't know what the heck it was." So it's not foolproof, even when they can hear it.
But my jingle bell experiment worked so well I'm going to buy a Timber bell.
If I rode more often in heavy traffic I'd get an AirZound. But I wouldn't waste money on another flipper bell, no matter how well designed.
And don't count on any noisemaker short of a Doppler effect horn/siren being effective anyway. Tests have shown people can't even tell the direction or approach speed of a train from sound or vibration. Modern trains and tracks are remarkably quiet and vibration free now anyway, but even with noisy freight trains on older tracks people continue to be struck and killed or injured because they misjudge the distance and approach. Only the Doppler pitch shift has been shown to be reliable for indicating distance, orientation and whether the vehicle is approaching or receding.
In some anti-cyclist places, like NYC, you get summonsed by our local pig department for not having bells. They're useless (and worse, make the peds that do hear them even angried) but thats the law unfortunately.