All Chainwheels are available for all GG models. Gearing is a personal choice and depends on the type of competition and rider. The Enduro team (EC250,300 + 450) mostly run a 49T on the rear with a 13T on the front. But for events like WESTON BEACH RACE we use a 45T on the rear. Most colours available, however red and blue are in short supply and once stocks have depleted these colours will not be replaced.