Time trial bike frames are designed to focus on aerodynamic performance. Time trial bike frame geometry will create an efficient riding position, with forward facing bars, shorter head tube and steeper seat tube. These factors allow you to keep your arms and body narrow. At entry level, time trial bike frames are made of aluminium; advanced models utilise carbon fibre and the latest research. When choosing a time trial frame, sizing is crucial to sustain the tucked aero position; many athletes use a time trial bike smaller than their ‘normal’ road bike.