I'm against spreading rear stays, period. There are enough old frames out there that you can certainly find one with the proper clearances to fit whatever wheels you plan on using.
Yeah, I'm also against removing brazed-on components, cutting off derailleur hangers, and - I guess - against any modifications to a frame except for paint. So I'm a curmudgeon. I'm proud of it.
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Syke
“No one in this world, so far as I know — and I have searched the records for years, and employed agents to help me — has ever lost money by underestimating the intelligence of the great masses of the plain people. Nor has anyone ever lost public office thereby.”
H.L. Mencken, (1926)