You might have bags of room in there already for 700c, those look like some long drop calipers.
If you need calipers that long for 700c, 650b might put the rim too far away from the brake hole?
@yoshy started
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You might have bags of room in there already for 700c, those look like some long drop calipers.
If you need calipers that long for 700c, 650b might put the rim too far away from the brake hole?