I've not had any problems with bike theft (knock on wood!).

However, there is the occasional...jerk...who will play with the shifters...or loosen a QR...or let air out of the tires (Presta valves are an advantage here--few people know how to use them! But Schraders....well...!).

Even...especially when..the bike is parked at work. Indoors!!

I think I know who the culprit..or culprits, are though!

But, I never catch the ...(censored!), and cannot PROVE it! If I ever do catch the idiots, though....! POW!!!