I have a system that works. On my Moki 1.80 I first CLEANED ALL THE THREADS of the bolts and holes using brake cleaner. When that's perfectly clean of all oil, then use blue loc-tite on the threads. Use Permatex Ultra copper sealant on the muffler and exhaust port to make sure the exhaust-to-engine mating area is leak proof. There's no way it will come off after that. Make sure the bolts are long enough, I use the one that BCM sent. Not sure what size they are.