Tapered head tube and fork.For increased stiffness and improved steering precision, tapered head tubes (see image, on left) and forks pair an oversize lower steerer tube (usually 1 1/2-inch, see image, on right) with a standard diameter upper steerer tube (usually 1 1/8-inch). This combination sheds weight compared to straight 1 1/2-inch systems, and adds stability and stiffness when compared to straight 1 1/8-inch systems. The result is a bike that tracks better through corners while allowing for the use of standard stems.