Admittedly it's difficult to see how a handlebar could cool the entire body of a person but it’s backed by science. When a person's core body temperature elevates the body automatically increases blood circulation to the hands and feet to move heat away from the core. This turns the hands in to the radiators of the body. This means we can cool the body by cooling the hands. The hands are ideal for cooling the body because of a special property of the skin on the palms of the hands.

Most of the skin on the human body reacts to cold temperatures by constricting the capillaries cutting down blood flow. However the skin on the palms lacks this ability. The capillaries stay open regardless of how cold the skin gets. This allows for large amounts of cooling via the hands. Thus the entire body can be cooled with a handlebar.

Many motorcycle riders say it's too hot to wear safety gear in the summer.