Even though the official road opening for Tioga is always later than Ebbetts or Sonora, you may still be able to get through Tioga on a weekend before the official opening. I know a few people who have accomplished that. During the week, the snowplows are working, and they won't let anyone through. Check with the park ranger. They will not let a car through until the official opening, however, so your support car will have to go the long way.
Once you leave Crane Flat, you won't have any signs of civilization until the Mobil Station near Mono Lake. Tioga Pass Resort is closed in Winter, sadly. When I rode it several years ago, I brought a water filter and got water from streams near the road.
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Ride, Rest, Repeat. ROUVY:
terrymorse