the now discontinued Bike Friday Tikit , also 16" wheel like Brompton,
.. was made to roll on it's locked straight ahead front wheel, when folded.

their 20" wheel bikes were made for travel-touring, when folded and partially dismantled,
they fit in a suitcase, that (samsonite) suitcase has wheels ,
though, as a suitcase, it will go on the airport luggage trolley with a duffel bag of the rest of your touring kit..

their Llama & NWT are very nice bikes, made in Oregon.. they replaced the Tikit with a PakIt, also 16" wheel,
they're a lot lighter by not being a quick fold..





,,,