I've got some noise on my new setup. 3 days of use so far. Sug75 ring, EAI cog, KMC "Z" chain. It was worse when the chainline was off by 3 or 4mm (not for very long), but since reinstalling the cranks and having them all the way tapped into the spindle as opposed to the initial installation (woops...) things have quieted down now that the line is dead on, but there's a little noise every half rotation (not completely consistant). I'm hoping it's either because the parts haven't 'mated' completely yet, or a lack of grease issue... I haven't heard anything good at all about those Izumi chains by the way, NJS or Eco.