It's fixed as it's a Tachymeter scale rated for cycling i.e if it takes a minute to cycle 1 mile/kilometre you're doing 60MPH/KPH on the outer scale. The middle line is to measure the speed if it takes 2 minutes its 30MPH/KPH and the inner line is for me counting how many hours it would take 😂 Anything in between becomes self explanatory.
Sorry, no, I am not talking about the spiral tachy. The external bezel is a simple fixed 0-60 scale. Nothing to do with cycling. And a poor detail, imho
I mean it kinda makes sense since there are no minute markings on the dial, guess they wanted to put them somewhere?