1985-1986 Honda ATC250R Shop Manual, Page 7Get this manual
GENERAL INFORMATION
AFTER '85: Piston valve 34 mm (1.3 in) 3-8 mm (18-516 in) 16 mm (0.63 in)
CARBURETOR
Type Venturi diaThrottle lever free play
Float level Setting mark Air screw opening PE37A turns out
PJ03A 2-14 turns out 1,500150 rpm 3rd groove
Idle speed Jet needle DRIVE TRAIN Clutch Transmission Primary reduction ratio Gear ratio II
1 AOO150 rpm 2nd groove Wet multi-plate type 6-speed, constant mesh 2.652 2.570 2.062 1.667 1.333 1.083 0.884 3.000 (39T 13T)