The make, model, and serial number of the bike should be recorded and photographed. The article explains where this information is likely to be found on the bike. Recording the bike size is also important, since riding a bike that is too large for the size of the rider causes control problems. Although the size of the wheels should be recorded, the dimensions of the frame determine the size of the bike. The article explains how the frame is measured and the metric scale for different types of bikes. The tire size and surface should be recorded along with the condition of the surface on which the bike was being ridden. This suggests the kind of traction the bike was likely getting at the time of the crash. All accessories mounted on the bike should be photographed, along with the clothing worn by the rider. These provide an indication of the visibility and safety features of the rider and the bike. The bike's braking features and settings should be documented in detail, together with the mechanical soundness of the bike. The article also explains how to estimate the bike's precrash speed through witness statements and an examination of gear settings in multispeed bikes. In bike crashes with rider fatalities and serious injuries (cases likely to involve civil litigation), the bike should be secured and stored in the condition in which it was found. Although photographs at the scene are important, it is best to have the actual bike as evidence to bring in court.