I chanced upon a Japanese biker with a Dahon K3 who is constantly posting about his upgrades/progress. I'm also following his footsteps when I get my Dahon K3 too.
You can try upgrading your wheels with Shwalbe Big Apple 14 inch tires to cusion your ride. I believe Bike24 has them and can deliver in France, but they're a bit hectic lately due to the pandemic.

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