No reason mmmm oooooh,  because there is nothing like a small risk because every accident fir take person's life,  so you no fit say because of the low speed of a bicycle, it accident won't kill somebody because what if in a situation where the bicycle rider is run over by a car on a busy road,  take it as if someone results into the use of a bicycle to go to work instead of a car due to high fuel price?

So we have to put a lot of things in check when making some decisions or assumptions about the advantages of a particular thing.