1981-1984 Official Honda ATC250R Shop Manual, Page 7Get this manual
ATe 250R Carburetor Type Venturi dia Setting mark Float level Air screw opening Idle speed Jet needle Throttle lever free play Drive train Clutch Transmission Primary reduction ratio Gear ratio II III
GENERAL INFORMATION
Piston valve 27 mm (1.06 in) PE23A 18.5 mm (7.3 in) 1-38 1,300 150 rpm 3rd STAGE10 mm (316-38 in) Wet multi-plate type 5-Speed, constant mesh 3.250 1.900 1.591 1.240 1.000 0.839 3.385 (44 13 T) Left foot operated return system l-N-2-3-4-5 CDI "F" mark Full retard 17 BTDC12,OOO rpm 14 BTDC9,OOO rpm Primary kickstarter 12V 0.073 kW17,600 rpm USA model B8ES (NGK) N-3 (CHAMPION) Canada model BR8ES (NGK) QN-3 (CHAMPION)