I am finding that the obvious answer to this question is “use the existing cable routing and full – length outer” but here goes…
I got a Pomp and want to use derailleur gears. I got a clamp-on double stop for the downtube and want to route cables under the bb. Works fine for the front mech, but I need a cable stop for the rear. I bolted a Ragley cable guide on to the dropout but it won’t clamp the cable outer (even 5mm) securely enough.
My next idea is to araldite the cable outer in or drill a step into the guide (or fashion one with a stop from some plate steel I have).
Full length gear outer may be best as I can then run the brake cable exposed which should give me some rear brake (currently lacking)
PS I can’t drill through the dropout as the bit is stopping, presumably at the weld at the inside of the dropout, will that have hardened?