careful now wrote:
I found some normal modern skinny (1.75"),but the rim is too big for them.
does y'all know?
How do you mean "the rim is too big
Is the rim diameter (height) too big to get the tyre bead onto (tyre too tight)?
Or is the rim cross-section (width) too wide to keep the tyre seated securely (tyre too slack)?
Do you have the larger diameter rims run on junior "mini" type race bikes?
They used skinny tyres. Usually called inch+1/8 or inch+3/8 in the UK. No idea what you'd call them in metric.
These are "labelled" as 20 inch, but are taller than standard 20 inch BMX sizing.
But not as tall as 24 inch cruiser.
Your best bet is to find a ETRTO number on the tyre to find the exact size.
As usual, see Sheldon (R.I.P.)
Try Alan's in Wigan:
Lots more odd-sized race tyres here: