1989 Honda FL400R Pilot Service Manual, Page 217Get this manual
IGNITION SYSTEM
TROUBLESHOOTING
Weak or no spark at plug
11Try spark test with known good spark plug, WEAK OR NO SPARK 2Check spark plug wire for loose or poor contact at the spark plug cap, then try spark test againI
Faulty spark plug
II-G_O_O_D_S_P_AR_K
Loose or poor contact of spark plug cap
WEAK OR NO SPARK