Hi - I applaud your endeavor. It sounds like fun, and I envy you. If you can get hold of the Pacific Coast ACA maps 2, 3, and 4, you will get a good look at Portland to San Francisco (2 & 3), and San Francisco to LA (Map 4 mostly).
I did a very, very rough cut of where the ACA route generally goes, using GPSIES. The Oregon trip is about twice as long, and the LA trip has over twice as much climbing. As you plan in more detail, these numbers will change:
(1) Maps 2 & 3: 900 miles and 10,000 feet of climbing -- I've done AMTRACK from San Jose- to - Portland -- it is about 20 hours, and you will have to box your bikes. As long as you don't have same-day connections to another train or air, you should be fine.
(2) Map 4: 500 miles and 25,000 feet of climbing -- I've not done AMTRACK from LA to San Jose, so you will have to check their schedules. I would not schedule same-day train or air connections as your arrival.
The weather is getting ready to change. I live in San Jose (south end of San Francisco Bay), and we have had rain already and a cool spell, with a heat wave about to roll through. From now until the true rainy season hits, the weather will be unpredictable and the winds will soon begin to shift from northerly to southerly.