Three road platforms compete in the finder. The Spear RDC is the all-rounder — seven sizes from XS to XL, including two dedicated racing fits. The T1600 Ultra is the aero racing pick, available as a frameset or a complete Di2 build. The SLC5 is the superlight, sized by seat tube from 440 to 540 mm.
The finder asks four questions and reads the manufacturers’ size charts against your height and inseam. It recommends only sizes that exist as real variants, links straight to the product, and the result prints to a single page you can bring to any fitter.
