Funny thing Keyven i've tried rolling a few bike brands and the easiest was the trolley rack for my Tern because it's based off or two wheels like a laptop bag which you can pivot around easily. But I would not use it in a narrow store cause the bike is still pretty wide and you'll end up banging around the aisles which the brompton has a much narrow fold. But for me if i was really going to go shopping in a tiny store best thing would be to ride my big bike and just lock it right in front of the store short term so i can have both hands free and not worry about dragging everything. Invest in a good lock park it in front of a highly visible area, folding bikes are not the end all of everything but we sure do like them
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