Hi,

The installed width of a tyre does depend on the rim width.

Your miles off talking about 23mm rims and 25mm tyres.
Its the inner rim width that matters regarding tyres.
23mm rims take 40mm to 50mm tyres typically.

15mm rims take 23mm to 32mm tyres.
28mm is a nice size for a training tyre .

rgds, sreten.

I think my rims are ~ 15mm. They are ~ 20mm outside
width. Fitted with a 30mm rear and a 32mm front.