I am running 5800 105 on a 84 team miyata. The brakes are rim and speced for 28mm (700 rim) .... I have done both vittoria corsa and Conti GP 28ss with this setup. and actually have 30mm corsa control tubies. I have also run 28 mm in a 89 miyata 1400 and 90/91 de rosa.
I would check for frame clearance, because with the right brakes you can do 28.
Only issue i has was having do deflate the tire to get in an out
good luck
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(looking for Torpado Super light frame/fork or for Raleigh International frame fork 58cm)