Recently bought a 1998 Valkyrie with 36K miles on her. Just did a valve check and found this; I can easily wipe it off so it is really just a slimy coating. You can see the line of heavier sludge on the valve cover which is to the downhill side when you put the bike on the center stand. I assume oil pools there and cools when the bike is shut down leading to the build-up. The bike supposedly had regular maintenance but I never saw any records. The PO said he had Amsoil in it when I bought it. I now have RTS in it. Bike runs fine and everything else on the bike seems to have been well maintained. Think they just went too far between oil changes or is this normal for a Honda flat six engine?