What is the inside width of your rim used for the measurements and pressure? Rim width is more important. I have GP5000 tube tires. They measure wider on rims 19mm wide inside or wider for 25mm and up tire size. Then to make it more confusing Continental made some changes to narrow the installed tire a few years ago. Last with age they get wider.
Edit. Found some older data on 19mm inside Bontrager Aeolus 5 rim brake.
Conti 5000 25 mm 85 & 67 psi 27.4 mm 19 mm
Conti 5000 28 mm 87 psi 29.0 mm 19 mm
Edit. Just got a new Conti GP5000 and mounted on 23mm inside width Aeolus Pro 51s. At 75 psi with latex tubes they are 29.5mm wide. We will see how they stretch. The old 28mm GP5000 was 31mm when I took it off. It’s in the 19mm rim for trainer duties and is 29.4mm wide at 80 psig.
Last edited by biker128pedal; 10-01-22 at 07:36 AM.