OK, I just went through 2 sets of brand new tubes installing the tires, and now I need to replace another one. I was so careful with putting on these tires, but still managed to get a puncture in the tube. I've installed plenty of tubeless tires, but these little 12" tires with tubes are giving me headache. Are there any specific tire irons that I should be using for tubed tires? Any tricks, besides lots of soap and being careful?