B'twin triban 3 wheel upgrade help req!

pearceygy
pearceygy Posts: 56
edited August 2013 in Road buying advice
I got my son this bike for xmas and he now wants to upgrade the budget wheels/tyres, the problem that I'm having Is the wheel size ETRTO 571x13 which Is I believe equivalent to 650c x 23 Is hard to get hold of because everywhere I look It seems 700x23 700x25 is the standard.
I must be missing something somewhere surely wheels for this bike must be available If anyone can help put me straight.

cheers.

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