Road chainsets comprise of one, two or three chainrings and two crank arms, one on each side mounted at 180° to each other, they are connected to the bottom bracket axle and to the pedals. Bicycle cranks can vary in length to accommodate different sized riders. Major manufacturers typically offer crank lengths for adult riders from 165 mm to 180 mm long in 2.5 mm increments. It would seem evident that riders with shorter legs should use proportionally shorter cranks, while those with longer legs should use proportionally longer cranks. However, the exact length an individual cyclist feels most comfortable with may differ depending on the type of cycling they take part in. Bicycle riders typically prefer shorter cranks for fast cadence cycling such as criterium and track racing, while some riders typically prefer longer cranks for lower cadence cycling such as time trialling and mountain biking, where leverage is a priority.