I live in Orange County, hands down the worst county in Southern California for motorcycle riding. It's compact and crowded. The coastline, which is lovely, is filled with traffic lights and congested. You can count on just a few fingers the decent riding roads.
By far the longest and most famous, that segment of CA-74 known as Ortega Highway, ends up being a nice transit point to much better rides in Riverside County and San Diego County.
In fact, San Diego County may be the best of the Southern California counties for day riding if you live in Orange. Great roads are only 60-90 minutes away, and the county is full of them. Just look at all the yellow, orange and red roads on my Butler map:
After picking up my bike from getting a fresh rear tire on (the OEM Pirelli Scorpion Trail lasted about 7K miles, not too bad but not great) I headed down the 5 to pick up CA-74 for the ride inland. Ortega is a nice road, not the best on the ride and typically fairly crowded, but if you're content to enjoy the scenery while you sit behind a train of six cars behind a contractor's pickup, then it certainly beats the interstate.
After Ortega, CA-74 turns into a gaggle of side streets and interstate stretches followed by a lot of stop and go traffic in Hemet before it really comes alive just east of town. Within minutes, the road starts winding up in elevation, the temperatures cool down and the scenery turns rustic and colorful. CA-74 is a California Scenic Route, as the signs start to declare at this point, and the designation is well earned.
This segment of 74 connects to three great rides: 243 up to Wrightwood, 371 tp San Diego County, and the Pines to Palms Highway. I've done them all, and they're well worth it.
On this ride I take 371 down to 79 for a late lunch in Warner Springs. 371 is not terribly twisty but very scenic, with vistas much more rural and expansive then a stranger to these parts of Southern California might think.