The law say yes. But while riding I trust better arm signals and being defensive by looking around you than stock horns. So, like most custom builders I have removed and thrown away more factory horns than I will ever install new aftermarket ones. But if you feel like you need one, at least choose one not destroying too much the look of your bike and louder than your stock one. FYI, a stock horn is pulsing an average of 85 dBs, quite not enough if you want to be heard. These new ones called Mini-Beasts blast 128 dBs to increase your (sense of) safety on the road. A complete line of designs and applications is available for American & Metric Bikes. Go to Tri-Tec/Sales Dimensions.