Red Loctite and 3/8" star washers on the back side. Got some BMX chainring bolts from Bikepartsusa and had the same problem. An ace bike mechanic friend of mine made the suggestion and it's been almost 3 years now. I changed the front from a 46t to a 48t and added a couple of links. That's the only time they've been loosened and retightened. They're still goin' strong.