Complex sentence: The pacer is standing or sitting upright on the motorbike to offer a maximum windbreak, and the handlebars are extended to facilitate the stance, his leather suit standarized as not to handicap a smaller person.
Split into simpler sentences: The pacer is standing or sitting upright on the motorbike to offer a maximum windbreak, and the handlebars are extended to facilitate the stance. The leather suits of the pacers are standarized as not to handicap a smaller person.