Here's the sizes to clear things up:
700c/28" = 622mm ETRTO
650c/26" = 571mm ETRTO
600c/24" = 520mm ETRTO
The ETRTO measurement is the tyre bead seat diameter, roughly the middle of the brake track for a tub rim.
I can still get Vittoria Junior tubs in 600c/24"/520mm. They're a black file tread, skinwall tub 21mm wide, good training tub at 260g. I'd have to order them in, but around £18 each.
Rims are also available:
Mavic CX18 28 hole, grey, 18mm wide, 12mm deep, double eyelets, 285g, £35 each
Mavic GL330 28 hole, grey, 20mm wide, 13mm deep, double eyelets, 315g, £25 each
Mavic Sport, 28 hole, grey, 22mm wide, 12mm deep, no eyelets, 300g £12 each
Ambrosio 24", 28 hole, £27each
Any other interest? I could make up a bigger batch order.
All the best,
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