Originally Posted by
non-fixie
Over time the tires seem to have grown in width, and are now approaching the chain stays. The vertical drop-outs are not helping either. Not rubbing yet, but ...
I need to find me another frame ...
OK if you want, but indenting this one some more is an option. It's actually easier to increase an existing indent, because the tool naturally aligns with the valley.
Or you could use smaller tires. The Pari-Moto is a nominal 38 mm, right? Maybe try a Hutchinson Confrérie des 650, or a Grand Bois Cyprès. Pari-Moto also came in wider sizes, I wanna say 42 and/or 48 mm (check me on that), so if you have those, then you just need the 38 mm P-M or some other tire that wide.
Another frame might be the most fun way though. Early-70s PX-10 or lots of similar vintage French bikes with the factory-indented 531 stays comfortably fit 42 mm tires with no extra indenting needed.
Builders from any other country could have used those same stays, but not many did, I mostly see them on Frenchies. My '58 Follis for example, full 531 DB racer, intended for 28" sew-ups, but is quite happy with 650x42b (GB Hetre).