This aint a new topic ( means less than a year old). I called Eagle on this and their recommendation was .016" I believe. I also thought that more clearance ment more oil slung on the cylinder walls. I was shown ( mathematically ) by a poster that I was wrong. Also heard from some members that they ran as much as .070" with no problems. It appears there are more issues with tight than with loose. Keep this in mind; the rods do jump from side to side as they travel up and down ( IMHO ).