I heard the BG 65ti has a longer durablility, but does it lose tension easily? BG 80 has more repulsion but less durability, should I have it at a lower tension compared to bg65ti on the AT500?
BG65Ti is really durable, but playability doesn't last. I only tried it once, but playability dropped by a lot and I eventually cut it. I'd recommend BG80. You lower the tension, not because of durability, but because it's a much stiffer string. Lower the tension by 10% at least.
You only lower BG80 or BG85 tension by about 10% relative to other strings if you want the same resilience, not because BG80 or BG85 are stiffer strings. The reason is that BG80 and BG85 have a sliver of vectran that winds around the inner core of the multiflaments, and vectran has an entirely different dynamic stiffness-vectran has a sort of built-in springs. In other words, BG80 with 10% less tension will produce the same resilience as another non-vectran string. AOTBE vectran strings will hold tension better than other strings. If a string is 100% vectran-currently there are none, except for racquets-there will be no tension loss, other than from lose knots, over the entire life of the string.
