After visiting Tehipite Valley and Cedar Grove at least 4 times each, I had this curiosity about the trail-less section of the Middle Fork of the Kings River between Yucca Flat (at the confluence of the Middle and South Forks) and Tehipite Valley.  A bit of Googling turned up a report by a guy named Ron Hudson who did a 4-day trip from Yucca Flat to Road’s End.  You can read that report here:
http://climber.org/reports/1999/477.html
Another good article describes the area and John Muir’s impressions of it here:
http://www.summitpost.org/canyon/223342/kings-river-canyons.html
The image below shows the confluence of the Middle and South Forks of the Kings River.  The Middle Fork is on the left:
(source: http://www.summitpost.org/image/233345/223342/kings-river-canyons.html)
Here is a map of the area.  The route I hiked is in yellow:
I arrived at Yucca Point at about 10pm on Friday September 3rd and hiked down the 1000 feet or so of switchbacks to the confluence.  It was windy all night and I didn’t bother hanging my food (I just clutched my new Arcteryx 50L drybag/backpack) and in the morning I could see the smoke blowing down the South Fork from the Sheep Fire.

I boiled some water for oatmeal at tea and was off up the Middle Fork by about 7:45 am.  Ron Hudson had attempted this canyon on September 17th on a normal snow year, and I was trying two weeks earlier it in the unusally heavy snow year of 2010, so I can only assume the flow was higher.  He mentioned he never had to swim, but I swam multiple times using my pack as flotation up the pools where the rocks and cliffs made it a more appealing option than going around in the rattlesnake and poison oak filled forest.
Late in the afternoon, after and tiring and stressful day of constantly making my way up the canyon, I made it to the entrance of Little Tehipite Valley.  It was very reassuring to see Tehipite Dome in the distance up the canyon.

As expected, I saw a ton of nice trout in the river.  When in the National Forest, the regulations say barbless hooks and catch and release only, but once inside Kings Canyon National Park, eating fish is allowed.  There was a nice open area in Little Tehipite Valley with a great campsite complete with benches and a grill.
The highlight of the trip was arriving in Tehipite Valley, quickly catching a couple of trout and frying them up with garlic, shallots and ginger over the fire in my campsite in the desert area beneath the Dome.  The tehipite fire had burnt a good portion of the west side of the valley, so I stayed a little further east than usual.  A warm wind blew down the valley all night.
On the trip I saw a juvenile rattlesnake, a large kingsnake and what I believe was a coral snake.  My biggest fear on a trip like this was being bit by a rattlesnake. Here is a video I took of a California Kingsnake:
That or slipping and breaking an ankle alone in an area where you can hike all day and usually don’t see a soul.
In the morning, I was hiking upstream by 7:45am.  You could still see some smoke in the air from the Sheep Fire as the sun was rising over the Monarch Divide.
There were a ton of annoying flies that were impervious to insect repellent and constantly divebombed into my ears and eyes.  I found myself walking for miles using my arms as human windshield wipers for gnats.  Kinda took the pleasure out of an otherwise nice morning hike.  The bugs did lighten up as the day went on and there were some beautiful sections of forest.  Until around this point, I hadn’t seen anyone.  Then I bumped into a big guy who calls himself Hidey Coyote and had 20 days worth of food in his pack.  My 3-day pack was only about 25 pounds and I needed every bit of weight savings for what was to come.
My initial plan had been to hike cross-country up Kennedy Creek to hook up with a trail that went over Kennedy Pass to Cedar Grove, but after looking up the 4000 foot creek canyon and being unsure whether it was passable, I opted for the surer route over Granite Pass as Ron did.  I knew that if I didn’t call my Dad by late Monday night, he would get worried and likely launch a search effort for me, so I had to make it out by then.  What I failed to notice was that Ron took four days to do what I was about to do in three.
After wasting some time trying to find the best place to cross the river to the South side, I reached Simpson Meadow at about 3pm.  Unexpectedly, I saw a pretty blond ranger preparing for something near some bear containers.  She said she was not a ranger (just a botanist) studying the meadows and was actually about to help with a search and rescue (SAR) and “had I seen a middle-aged Korean woman”.  Hidey Coyote was about as far from an asian woman was you could get, I said.  When I asked her if I was heading the right direction to the switchbacks, she said “Ah, you’re gonna climb the Bitch”, and told me I’d better bring a lot of water and that I could drink straight out of Horseshoe Creek without filtering it (the rangers do it all the time).
The switchbacks were long and arduous.  It was clear to me now that I had bitten off more than I could chew. I climbed at about a rate of 1,000 feet per hour from 6,000 feet up to 10,000 feet.  There were some big bear tracks here.
I climbed until the sun set and then kept on climbing.  These were the worst switchbacks I had ever encountered.
I didn’t reach water and a suitable campsite until after 9pm at Dougherty Creek.  After descending about 1,000 feet in the darkness, I found a great campsite that was stocked with firewood.  I made a big fire to warm myself up and cooked some cous cous with more olive oil, garlic, shallots and ginger.  I was a bit worried about my 45 degree sleeping bag, but the bivy sack I brought added about 10 degrees of warmth and I was fine at night after wrapping my safety blanket around me to get an initial bit of heat.  My body was sore and aching after 13 hours of hiking that day.
On Monday morning, I rose early and climbed up to the 10,700 foot Granite pass.
My knees started aching when descending Granite Pass, and I still had 6000 feet to go!  The rest of the day was a surreal drudgerous ordeal.  I had brought my iPhone 4 in order to use the Topo Maps application, but it turned out that listening to music and a book on tape was exactly the distraction I needed to get through the day.  I passed through lovely meadows and the smoke got thicker as I descended toward the floor of the South Fork.
I stopped to refill my water bottle at Tent meadow and had a conversation with a guy who told me his son uses a thing called a Spot Tracker when he goes on solo trips. I’ll have to get one of those.  There are some nice flowers in the Tent Meadow area.
I listened first to Mason Jennings, and decided I would take my Mom to see him to the Friday night show at Yoshi’s in SF when I returned.  Then I continued listening to “The River Why” on tape which my Dad had recommended and I thoroughly enjoyed.  The last couple thousand feet took what seemed like an eternity as my feet were moving so slowly.  The pines on the flat valley floor slowly getting closer and closer but always remaining far away.
When I finally reached Road’s end, I jumped off the big rock into the river which felt fantastic.  A ranger gave me a ride to Cedar Grove and introduced me to a couple of guys who work in the caverns who said they would take me back to my car at Yucca Point.  We stopped along the South Fork to watch the “controlled” burns envelop entire trees and shoot off cascades of sparks in the night.  It was beautiful, but I wouldn’t try to hike the whole thing in a three day weekend again.