I was surprised that I did pretty well, not too scared and drove a little above the speed limit, mabye 40 to 45 mph.
Are we interpreting the advice / suggested speed signs in turns as the "posted" speed limit for the Ortega. The posted speed limit for the highway is 55 mph. While there are sections that you may not be safe in driving that speed in a "cage" (auto, truck), it is 55 nonetheless. Speaking strictly of traffic laws, the other law that is unfortunately rarely enforced by the CHP, Sheriff, and park rangers (yep, sworn rangers can enforce state law) is a less-known law that is suppose to prevent someone from delaying 5 or more vehicles. The "intent" of this law is prevent aggression. Unfortunately, a number of motorcycles and (more recently) cages just decide to pass over the double-yellow to get around the slow driver; this act unfortunately, in my opinion, has established an expectation that if you see someone behind you, especially a motorcyclist, you expect them to pass you illegally at some point so why pull over...
To put it in very simple terms, please remember this: "If no one is in front of you, and someone is behind you, PULL OVER (when safe to do so)." It doesn't matter what your speed is...just pull over.
I happen to ride a motorcycle on most days when traveling the highway. I have no problem in maintaining a speed of 55 over the entire length of the highway, but when driving my truck I have to slow down in areas. If someone comes up behind me, I pull over when I can. When driving my motorcycle there are only a few circumstances that I'll pass someone illegally (but only when safe); 1) someone eating sunflower seeds and spitting them out with me behind them...nothing worse than getting a chewed shell on your face, and 2) someone who is smoking and letting the ash fly out the window...nothing like a burning ember in your eye.
Anyway, in summary, just be courteous and as others have said, enjoy the scenery and the break between work and home...but keep an eye on the rear-view mirror too
Have a great day.