RS400R is parts kit for racing by CBX400F which had been distributed from RSC (as of now HRC). There is no RS400R racing model, people just attached these parts to 400F for racing.
[ see photos of Mr. F-3's 400F. RS400R parts are attached. ]
# power up kit 06140 POWER UP KIT 1 80,000 # it includes; # gascket, piston, cam shaft, chain and etc. 12191 GASCKET, cylinder (1) 300 13101 PISTON (4) 3,000 14100 CAM SHAFT, inlet (1) 20,000 14200 CAM SHAFT, exhaust (1) 20,000 # oil cooler 15600 COOLER COMP, oil (1) 15,000 # mission kit 06230 6 SPEED MISSION KIT 1 70,000 # it includes; # shaft, gears, sproket 23210 SHAFT COMP, main (1) 8,000 23220 SHAFT COMP, counter (1) 10,000 # master cylinder 43500 MASTER CYLINDER ASSY,rear (1) 12,000 # cowling kit 06640 COWLING SET 1 63,000 # it includes; # cowling, lens and etc. 64100 COWLING, front (1) 35,000 64101-286-970 LENS, cowling (1) 12,000 64231 STAY A, cowling (1) 7,000 64232 STAY B, cowling (2) 800 64233 STAY C, cowling (1) 5,500 # seat 77100 SEAT COMP 1 72,000 # misc. 12010 HEAD ASSY, cylinder 1 70,000 37240-NA4-000 TACHOMETER ASSY 1 18,000 51400 FORK ASSY, R front 1 30,000 51500 FORK ASSY, L front 1 30,000 52400 CUSHION ASSY, rear 1 40,000