Suzuki DF25/DF30 Four Stroke Service Manual, Page 50Get this manual
PERIODIC MAINTENANCE 2-23 (5) Connect the tachometer lead wires as follows: 34200-92E02Engine tachometer Yellow lead wire to the YellowBlack lead wire of CDI unitGray lead wire to DC 12V power source positive terminalBlack lead wire to DC 12V power source negative terminalSet the pole selection switch in the tachometer to "12"
CDI unit
(6) Start the engine and warm up engine as followSummerminat 2000 rminWinter10 minat 2000 rminYellow Black Gray 12V Battery Tachometer