Here is some info on bikes on Amtrak trains.
Since several bikepacking routes offer Amtrak railroad access, it can be a great way to travel to or from your trail.
If you haven’t been on Amtrak trains out west:
Coach seats on the train are similar in size to business class on an airplane, and include thigh and foot rests as well as drinking water fountains in the cars.
If you upgrade to a sleeper you get meals included and free coffee and juice in your car as well as a shower in your car. There is usually a bar car serving drinks and snacks as well as a sit down dining car.
If you reside outside the US there may be some interesting railpasses available if you want to do some longer train trips in a short time. You can buy a ticket and interrupt a train journey anywhere along the route then get back on and continue.
Trains are frequently delayed. On a recent yourney we had a medical emergency that forced a stop, but more common is having to wait for freight trains.
Be aware that you can
only take your bike if you board at a train station with checked baggage service.
We left our bikeboxes and duffelbags with street clothes in the station while we did our ride, there might be a fee for that, but we got lucky and didn't have to pay anything.
Amtrak will NOT take the bike wedge shaped Aircaddy box. however they have their own boxes which they give you for free if they are used, else they are $20. Bike fee is $10 per bike and max weight for the total is 50 lbs. Their boxes are huge. All I had to do was take off pedals and front wheel, and loosen my stem faceplate. I have a huge bike(I am 6’5″ and sit upright). At one station they gave us tape, at another they did not. I suggest bringing your own.
Bikebox handling was clumsy leading to a dropped box, so some padding (we used our handle bar bags) might be good.
Dirtrag had a good article on bikes on trains a while back:
http://www.dirtragmag.com/webrag/dirt-rag-rides-railsAmtrak bike policy:
http://www.amtrak.com/servlet/ContentServer?c=Page&pagename=am%2FLayout&cid=1251621565020