Originally Posted by dtglenz
I usually buy tires that are on sale.
- The size is usually 700 X 28.
- The air prssure I use is what is recommended on the tire, usually 100#.
- Tandem weight, including the weight of the tandem, I'd say about 425#.
- We were going around a corner and the tire rolled under the rim and we almost went down.
- I just want the most reliable tire and tube I can get. Safety is our main priority.
IMHO, you might want to consider running a larger diameter tire... something like 30mm Avocet model or a 32mm Panaracer Pasela. Although not necessarily essential, you might also consider using wire-beaded tires vs. foldable kevlar bead models if the tires you've rolled off the rims were kevlar beaded.
PSI values on tire sidewalls are a general guideline and, instead, tire PSI should be adjusted to get the right tire shape (slight bulge when fully weighted). For tandems, this normally requires a bit more pressure than the sidewall number, e.g., if the tire says 90psi, expect 100-105psi, if it's 100psi, probably 110 - 115psi.
Therefore, getting back to your question, of the two tires listed I'd recommend Conti Gatorskins in 700x28 since it's the only one of those two that use a wire bead. But, again, plan on running the tire pressure at or a bit over the sidewall rating as necessary to get a good tire shape: again, there should only be a slight bulge in the sidewall when you're both on the tandem and rolling along. If it looks flat, it needs more air. If it feels too harsh and there's no sidewall bulge, it's probably overinflated.
Finally, there is no such thing as the perfect tire or a practical flat resistant tire. The best you can hope for is to go with a good tire that balances your expectations for durability, performance and cost, keep it properly inflated, and do your best to stay out of the gutter and away from the edge of roads where debris collects that can puncture your tires.
Oh yeah, as for this weekend I suspect your front tire was under inflated... What kind of tire were you using, did it have a kevlar or wire bead, when did you last top it off with the pump and how much PSI were you using in that tire?