You can wear whatever safety gear you want on a bike. It's just that bicycle crashes are usually so low energy that motorcycle gear is overkill. On a motorcycle

You can wear whatever safety gear you want on a bike. It's just that bicycle crashes are usually so low energy that motorcycle gear is overkill. On a motorcycle, road rash can grind flesh off down to the bone. Nothing's stopping you from wearing a motorcycle jacket, full finger gloves etc. every time you get on a bicycle though.