50mm tires on 19c rim
This is my first post here. A little background; I live in the Netherlands and cycling has always been an intgral part of my life, not as a sport, but as a part of daily life. Until now (I'm in my mid-30's), I've never even owned a car.
Not too long ago my Gazelle city bike was fitted with 50mm (622) Schwalbe 'Fat Frank' tires on a standard 19c rim. Unfortunately, within 48 hours, I got an unexplainable flat rear tire (see photo). It did not happen while I was riding my bike, but I found out about the next morning so it wasn't a sudden flat. I checked the tire and tube thoroughly, but I couldn't find any sort of damage of puncture.
Since the Schwalbe tire was 50mm and the rim was a rather narrow 19c, I'm beginning to wonder if perhaps the tube 'slipped' between the rim and tire and thus was ripped apart which caused the flat. In general, opinions about fitting wide tires to narrow rims differ. Some say it's not a great idea, others say it is not a problem. At least according to ETRTO norms, it shouldn't be a problem. I a bit worried though if it a good idea.
Does anyone has any insights to this matter? Is it in general a good idea to fit 50mm tires to a standard 19c rim?