There is still water flowing up in SBNF (lower elevation) so Halfmoon sounds promising. What about Cottonwood? That appears to to be higher than Halfmoon, and near a creek as well? Is the 127 considered to be Miller Jeep Trail as well? Or does MJT not start until the 128 crosses?
Chuchupate campground is looking like a great central hub, and right bellow Frazier. I have heard Frazier mtn. is a blast to ride. But damn, that paved road is going to bring the people in! although the weekend AFTER 4th of july might be dead????
Are you allowed to camp anywhere in LPNF? Or designated campgrounds only?
maybe this is where ill end up on the 9th and 10th. Would my kid and wife have any easy stuff to ride? fireroads... really easy trails?

Too old, fat and oft injured. That said there are plenty of fun trails with smaller cliff issues but basically not that bad as Sun said. As a matter of fact there are plenty with little or no cliff issues.
I think when it is really hot going up on Tejon is smarter. You conserve your water better and it is a better trail to warm up on. Yes, I know going up Frazier is fun for the most part
make sure you have plenty of water. I have rode a couple of times with people who ran out of water up there and they were in bad shape. When the weather is nice it is a whole different story and not so much a problem. It is so stupid we cant ride down the road on Gold Hill. It would make loops so much better! Sometimes on weekdays it is better
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No punishing agenda here from me my friend.
Basically the deal is eat good before, snack on the ride as you probably will not see the truck for 4-5 hours. Water and hydrating before will be VERY important. The elevation takes a lot out of you as it is dry AND hot relatively speaking.