A 700c with a 28 is almost the same as a 650b with a 46mm tyre. Rim/tyre combinations may vary.
Plenty of data here: http://www.bikecalc.com/wheel_size_math
Cheers for that link. Plenty of info there to keep me occupied for the evening.
@Thrust started
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A 700c with a 28 is almost the same as a 650b with a 46mm tyre. Rim/tyre combinations may vary.
Plenty of data here:
http://www.bikecalc.com/wheel_size_math