I'm Dutch, you're almost right. Most people won't even reach 15 mph. Speeds around 10 mph are more common. Funny thing: wearing helmets is much more common in

I'm Dutch, you're almost right. Most people won't even reach 15 mph. Speeds around 10 mph are more common. Funny thing: wearing helmets is much more common in Germany. If you see adult cyclists wearing a helmets on upright bikes they'll speak German most of the time :) Generally I wear a helmet if I'll be doing more than 15 mph, or riding through a city.