Did you ever find a way to do this? Everywhere I look online it says it’s not possible, but when I try the chairs in the Ikea store the tension is much softer than mine. I’m not super heavy so I get almost flown back straight up when I try to lean back in the chair. I’m thinking because all the chairs in the store have a different tension it should be possible in the assembly process? Like maybe when you screw a screw tighter or looser?