Help

I know most ofyou are fans of Laura Gemser and of Italian sex comedies with Gloria Guida and other sexy 197s sexpots. I rented a movie back in 1990, in a mom and pop video club. It was a italian comedy that featured something I have never seen before or since. A sex scene on top of a motor bike (in someone's garage). The girl was gorgeous, and one of the famous lines by the boyfriend was "Put on the helmet, it will be better". I also remember a scene in the movie were a brunette was talking to her beau and kept changing her panties during the conversation. Year is 1975-1978. Any help?? Thanks!!