Mountainbiker.
I think that your link-video is not good. This is a picture of a bike .. e-Tikit ..
I have two main lights, which are used when the darkness came,
and 2 small lights, which are used before the great darkness, they blink or it remains fixed.
PS..
I change the location of my little lights, and also the horn.
################################################
A friend of mine uses his e-bike all winter.
It installs large tires mountains (without spikes) and he said, he has no problem.
It is true that the city, the streets are mostly clear.
But his bike is still very very dirty. Calcium is a lot of dirt ..
He cleans his bike in a car wash. ... with a jet, soapy water.
#################################################
I have a little video of my Bike Bicycle Handlebar Ultra-Loud Alarm Bell Ring.
I did several tests on the bike path, this after-noon, and I can tell you that people hear this horn very well.
This horn is essential, his sounds are shrill,...
but not enough to be cast out of the cycle track, by big arm.
I also installed a union (dean plug) between the horn and the start button. It will easily extractable.
(( My camera is of poor quality and the sound is not clean. There is a background noise .. ))
...but this gives you some idea of the 6 sound of that horn.
Adjust your volume loud enough, and you'll have an idea of the sound of this horn.
YouTube - BIKE HORN TEST