Yes you can get away with putting your bike on a KTX, any train car or under a bus, but it may involve taking off your wheels, having to make sure there's space between all the luggage or pretending not to know rules and hoping not to be caught.
And so traveling between cities, if there is a train option with cycle racks available that will be my first option. There's always space, no taking wheels off or stressing about being caught.
But how do you find trains with bike racks? When do they run? Between which cities and where can you buy tickets or check? These were questions that kept me from using this care-free service. The answer is the Korail App!
Unfortunately it's all in Korean, but if you know your Korean letters you can book tickets easy on your phone and secure a bike seat and know which trains have bike racks. There are lots of tutorials online that explains how to use the Korail app, just do a simple google search, but they don't show you how to check for a bike rack.
I took a few quick screen shots and tried to show how you would find a ticket for yourself and your bike. It's not pretty, but hopefully it's useful.
I've taken the train from Haeundae to Ulsan and back a few times now, once I did not even have a bicycle ticket, because they were sold out. So I checked the time of the bicycle train and just got on it anyways, there's 5 bike racks, but lots of space available for more bikes.
Once you know the time the trains come and go, it's pretty much the same for each day. Every day at 7:38am a train with bicycle racks leave from Haeundae station.
For the trains near Haeundae and Ulsan the bike racks are always in the cafeteria car, number 4. If it's not a bike friendly train they take out the cafeteria car, so the train has car 3 and 5, but car 4 is just missing.
I'm already planning my next train cycle trip, maybe Miryang or Gyeongju...
Any information about cycling in South Korea.