I will add some points:
-If done by driving to the locked gate at the furthest point you can drive, this would be significantly easier. If you have a mountain bike and wanna try it, I suggest doing it that way. If you're super-bike-mans, going from where we did at Grandview at 8,500 is good, or Big Pine if you wanna be super duper big mans. I'm glad we did it via Grandview.
-I had a big bike tour planned for this year but had to cancel because I got a new job. Riding up White was a goal, and I would be doing it from Big Pine, probably camping up on the mountain. I had planned to camp near Silver Canyon Road so I could leave most of my stuff there and go light to the top, then bomb down to Bishop. I would've thus done this full on badass style from 4,000ft to the top, but only out of necessity. What is and is not 'enough' on a ride is relative, and I'm glad Dima talked me out of that route. I am hard headed and often only see things one way. I like how we did it, and I got to descend to Big Pine, so it was like getting a huge bonus.
-I would suggest a mountain bike with suspension for this route, as well as about 6 liters of water, a meal, and a buncha snacks. We brought 8-9 liters of water or so each and I had 2+ left when we ended. Water is one of the heaviest things you carry on a bike, but I never feel bad ending with more water. I think a hardtail is fine, a full suspension would be very fast and fun on downhills but limit your water/cargo capacity. If I could have any bike just for the dirt part, it would be a lightweight hardtail with wide tubeless tires (up to 3"), a dropper post (excellent for descending from summit!), lowwww gearing, and the ability to carry 3-4 liters on the bike. Then, a small pack on your back for other water and bits.
-Temps were comfy, 60-70's and 50's near the top with occasional strong winds. Protect yourself from the sun, drink water often to avoid AMS, eat small amounts often, etc.
Dima and I split at the very tippy top of the paved section on the way back, around 10k. He went to the car to pack and drive down and I aired my tires back up, cleaned drivetrain, and began what was easily one of the most amazing descents of my life. Descending paved roads as fast as I can is one of my favorite things in life, and this one gave me 6k of loss with practically no traffic and awesome, expansive views. The descent to the 168 on White Mtn Rd is super fun. I suggest you have wider tires than a typical road bike, as there are big 'cracks' in the pavement, which are smooth so they're not a huge deal but if I were on 25-28mm tires I feel I could've eaten it, and would have to bunny hop the joints each time. There are a handful of em near the top of the descent, and a few sprinkled here and there the rest of the way down.
I think 700x40 is the ideal size for a long range paved road speedy bike you cover enormous distances with comfortably while still bombing mountain passes. I am on 650x48, so those cracks aren't a big deal at all, I just don't lean on em but I don't hafta jump em. Since this was my first time descending this road, I didn't haul ass, I just went regular fast. None of the corners appear to be decreasing-radius or anything tricky, so nothing 'snuck up on me'. I am pretty cautious so I didn't worry about eating it. There is obviously no guardrail and if one was to crash off the edge, they could fall for a very, very long distance and probably die and nobody would find you or evidence of your bits for a while.
The views are amazing, and I started around 1930, so the sun wasn't in my eyes and the light coming across the Sierra to my right was awesome. Super beautiful. There was a couple hanging out at the viewpoint not far from the top and I screamed past them with my brakes squealing on corner entry, and I got my lean on and stunted on em. They didn't see me until the squealing brakes made em look and I boned out. Super tight. Right afterwards was an awesome view to the right, looking down the mountain at some of the corners below. One of the corners reminded me of the super steep switchbacks on Baldy Road above Ricehouse Canyon, so I applied a lotta brakes and took a sorta late apex/recovery line exiting wide. I take more recovery lines on descents I'm unfamiliar with so I have more room for error if I come in too hot. I descended Pikes Peak from the summit to the pits at 9k and crashed into our work truck cause I came in too hot once, and I think of that a lot. I also nearly creamed a Ford Focus on that descent. Amazing ride, that was.
There are some flatter parts before reaching Grandview, so I was only doing about 21mph there. I spotted Dima packing the car up, so I felt comfortable knowing he was behind me in case I had a crash or a mechanical on the way down. Knowing you have help takes a lot of the stress away. The road continues down until you hit a short and low angle climb, followed by a mostly straight but fast descent to the 168. It was getting a little darker, but there was a full moon, which is just absurd that so many good things lined up for me on this descent.
Nobody was on the 168 so I (gently) ran the stop sign, giving someone a heart attack somewhere, cursing cyclists. There was a little bit of nearly flat riding down to the west before the downhill began again, and I would go through the canyon. The first section is straight, and then it dramatically turns left into a super fun series of corners that I want to hit again and again. The canyon is narrow here, not in a crazy spectacular way, but in such a way that it forces the road to turn tightly as it runs to the south before turning west again. The road then enters this amazing narrow gorge with a tall rock wall on the left with striking green lichen. This section is a single lane, and I was lucky nobody was coming cause this allowed me to bomb down it very fast. The approach downhill gives sufficient line of sight to determine if traffic is ahead. I wanted to take a photo, but I didn't want to interrupt this awesome descent. You exit the gorge with a tight left right sequence, and the road straightens a bit all the way to the valley floor. It continues to serve up awesome high-speed corners with no surprises, allowing you to smash out at top speed. There is one dip where you go over a crest and cannot see the road beyond the crest, but it is straight after the crest long enough that you can just go straight and you'll have full traction for cornering left once you're over it.
There was a headwind blowing up the canyon, so I wasn't able to go as fast as possible, but I still managed 43mph at times. With no headwind and a 53t crank in place of my 46, I think I could manage a pretty impressive speed, maybe 50 something. I'm not very aerodynamic so perhaps some changes in that department would gain me a handful of miles per hour. The road keeps flying down this canyon straight at the Eastern Sierra as if on a bombing mission in Star Wars, and the terrain becomes more deserty and gets warmer, straightening out as the canyon widens and you leave the mountains. The terrain flattens out and you exit the last of the drainage, turning left and then right and slowing naturally as the grade eases. It was 80 something degrees when I hit the valley floor just as it was getting dark, and I had to begin pedaling towards the 395 where I took a break and waiting for Dima for about 30 minutes or so.
Truly an awesome descent. If you like bombing down awesome mountain roads, this is way up near the top of my list. Please go do it. If I could pick a bike for it, I would have a road bike with excellent hydraulic disc brakes favoring modulation over pure power, 700x38-40mm slicks set tubeless to a relatively high pressure so you don't get much bounce, slightly wider handlebars with ergo bends in the drops with extra padding there, 53t crank with 11t cassette, and maybe no big bag on the front like I had

, and no headwind. My back, arms, and hands were sore before I hit the bottom, so it was a long descent that really made me happy. Unforgettable.
Thank you Dima for letting me bomb this descent. I doubt I would've ever have been here without you, and having you do what we did so I could ride it was awesome.
Some numbers from my Strava:
75.91mi 10,233ft gain
Average speed 7mph, max 44
Moving time 10h 50min, elapsed time 14h 41m
My total has a longer mileage and higher speeds than Dima because of my extended descent, adding 20 some miles.
If done from the valley floor to the top and back, the totals are 94 miles 15,775 gain 10,315 loss.