Over-tightening the chain will put excess wear and tear on the shaft and gears. http://F.R.A.G.Ra.Nc.E.Rnmn%[email protected]/?a%5B%5D=%3Ca+href%3Dhttp%3A%2F%2Fwww.heart-hotel.com%2Fcomment%2Fhtml%2F%3F401013.html%3Egarage+Door+Repair%3C%copyright%3E%3Cmeta+http-equiv%3Drefresh+content%3D0%3Burl%3Dhttp%3A%2F%2F186.31.27.77%3A8002%2FActivityFeed%2FMyProfile%2Ftabid%2F56%2FuserId%2F312174%2FDefault.aspx+%2F%3E