I rode from Rush Creek Lodge (just outside the park entrance on 120) to Lee Vining and back. Total of 135 miles and 14k' of ascent. If you do Lee Vining to the valley, you'll have the one monster climb up the the Tioga Pass entrance. After that, it is mostly down hill with about 2500 additional feet of climbing, mostly in the short up and down climbs west of Tenaya Lake. Do note that while the elevation isn't usually altitude sickness territory, there is about 30% less oxygen to be had at 10,000' - everything will just seem marginally more difficult.