Sram force wifli 10 speed rear mech the sram force rear derailleur takes advantage of exact actuation an actuation ratio that delivers precise 3mm shifts in every gear along with the widest range of adjustment available delivering the best 10 speed performance in the sport with wifli the rear derailleur lengthens its cage and gets a slight variation in geometry to accommodate an 11 32 cassette the new range of gears is wider than the standard triple chainring system and saves well over 250 g