Yeas ago I motorcycled a lot, all over the world. I escalated to an air horn and hi-viz. But I pretty quickly realized that these made no tangible difference to the behavior of larger vehicle drivers. So I ended up for later vehicles with a stock horn and hi-viz only for heavy rain.

These days our family cycles a lot for commuting. It’s really easy to observe that people in vehicles treat us far better if we look like humans, wearing normal street clothes, rather than wearing high-viz or, far worse, cycling gear.

The bike bell is for polite notice, not alarming. The best alarm system you have is your voice, which is variable volume and tone. For ultimate effect slap the panels of cars, as it is very loud inside the vehicle.