i'd make sure the valves are clean also, if one was sticking upon closing this could cause the cable to pop off. you can buy the clip though if you want the extra security, my buddys m7 had issues with his popping off and he bought the clip off of i think an 07 m8 and hasn't had the issue since. on that note, on my m7 i have never had one pop off but i clean and check the valves and cables atleast once or twice a season.