Originally Posted by smashndash

yes internal width. External width is irrelevant for most discussions besides aero and brake clearance.

I have probably already said the following but whatever. Imagine you have 2 wheel systems: A is a 28c tire than measures 28mm on a 17i rim. B is a 25c tire that measures 28mm on a 23i rim. A will (probably?) be taller than B despite being the same width. This means you can run the tire softer without running into pinching or rim damage. However, tire B will feel less floppy at similar levels of softness.

Think of a car wheel/tire system. Oldschool 50-60 profile tires vs new “sporty” 30-40 profile tires.

If low pressures are causing squirm in corners for you, get wider rims. If low pressures are causing pinches and rim damage, get narrower rims.

Take this post with a grain of salt. I am a mere forum dweller.