I believe 14 is stock for the bike & your fit kit sheet calls for a 13 (right?). If so, I tried the 14.. it didn't allow for the correct chain adjustment.
At 8,000 ft plus the 13 will be OK but something a little shorter would be good to try. By memory the stock gears in the TS case are both 17s (?) so I bought a 16 & an 18 to give me lots of choices. At sea level one gear up is best. If your are ever on a trail stay with the 13 & stock TS gears. The bike's ratios are super tight thus 5th gear runs out quickly even at 8,000 ft. At elevation keep it short enough to use ALL of second even in the deep & steep.
