1981-1984 Official Honda ATC250R Shop Manual, Page 175Get this manual
ATC 250R
E lECTR ICAl SYSTEM
TROUBLESHOOTING
Engine starts but stops 1No spark at plug 2Improper ignition timing 3Faulty spark plug No spark at plug 1Engine stop switch "OFF" 2Poorly connected, broken or shorted wiresBetween AC generator and ignition coilBetween COl unit and engine stop switchBetween COl unit and ignition coilBetween ignition coil and spark plugBetween pulse generator and CD unit 3Faulty ignition coil 4Faulty CD unit 5Faulty pulse generator 6Faulty AC generator Engine starts but runs poorly 1Ignition primary circuitFaulty ignition coilLoose or bare wireFaulty AC generator 2Ignition secondary circuitFaulty plugFaulty COl unitFaulty pulse generatorFaulty high tension wire 3Improper ignition timingFaulty pulse generatorFaulty COl unit