1985-1995 Polaris ATV and Light Utility Hauler Service Manual, Page 387Get this manual
ELECTRICAL Ignition System Test Sequence ContCondition: Weak Spark: Spark will not jump 38" (1 cm) air gapSymptoms of weak spark: Perform the same tests used in the "No Spark" tests-Hard starting -Plug fouling -Loss of power -Misfire
Intermittent Spark: Fuel, compression and ignition can all cause what sounds like an engine misfireTo determine whether the misfire is ignition related, connect timing light to the ignition system and view the light while the engine is runningIf the light is consistent while the engine is misfiring the problem is not spark relatedIf the light is intermittent while the engine is misfiring proceed with the following tests-Install new spark plug and recheck-Disconnect the black wire at the reverse speed limiter and recheck