Road Chainsets are commonly available in two formats, double(race or compact)or triple. Double Race chainsets have 2 chainrings and will come with rings suitable for competition use and common configurations would be 53/39, 52/39 or 53/42 and will have 130(Shimano) or 135(Campagnolo) PCD’s. Double Compact chainsets have 2 chainrings again but are more suitable for Cyclo Cross, leisure use or hilly conditions and come with a lower ring size of 50/34, 50/36 or 48/34 with a 110PCD. Triples have 3 chainrings, these are commonly 53/39/30 so offer the widest choice of rings sizes but do require a long cage mech and a triple front mech.