Beautiful day in SF today so I went for a ride. As I was heading into the city at about 60 mph the rear end started to skate on me. I immediately pulled over and my tire was flat. Long story short and after getting billed $100 from the nearest cycle shop, turns out the stem just blew out on the tube (which is only 2 months old). Scary. It was a BikeMaster Tube. after researching I found that there are shipments from China where the stems are popping out of the tubes. Thank the Lord it was not the front tire! Anyway the rear was replaced with a metzler and I will do the same with the front asap. Just getting the word out to others with BikeMaster or other cheaper tubes made in China (without quality control...).