These lights are designed to work best mounted at the fork crown. The beam shape will be a little distorted when you mount them at the handlebars, but just a little. They have a standlight so they don't go out when you are stopped at stop signs or traffic lights. It takes some time for me to aim the lights properly. I like to aim mine so that they don't illuminate signs if you are close to them, but not too low. Basically just like a car headlight.