Am I missing something? Just poke your head through the main triangle of whichever bike is lightest and carry it on your shoulder.
If you have a sweatshirt or small pillow, that might make it easier on your shoulder/neck. Take breaks and walk with the bikes abreast if the bike is heavy. And be sure to bring some kind of proof of ownership, so you don't get pulled over or accused of thieving. (No one likes a bike thief.
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