2001-2005 Yamaha WaveRunner GP800R Factory Service Manual, Page 161Get this manual
IGNITION SYSTEM
IGNITION SPARK GAP
WARNING
When checking the spark gap, do not touch any of the connections of the spark gap tester lead wires! When performing the spark gap test, take special care not to let sparks leak out of the removed spark plug cap! When performing the spark gap check, keep flammable gas or liquids away, since this test can produce sparks!