Wanting to upgrade to a better front derailleur- the Superbe https://velobase.com/ViewComponent.as...113&AbsPos=253

But it does not have a cable guide stop like my old Suntour AR has- no mounting hole in BB for a plastic guide.

any kind of clamp on options for early 80's bikes (no brazing allowed)?

You can drill a hole for a plastic cable guide in the bottom bracket, what is the diameter of the seat tube

Look under the BB for a screw hole. Got one? Might have an M6 thread. Get a plastic, under the BB, cable guide for a few bucks. Might fit.

If there is no hole, you may be able to remove crank and BB cups/spindle, drill and tap a hole for that. It would negate the need to use a cable housing segment from the lower down tube to the FD like on your veneral Suntour AR. You would probably still have to route cable above the BB for the RD because your RD cable stop is above the chainstay on this bike. Is that right? If not, then I'm really confused about your bike and may need a picture or set of pics of your BB cable guide braze-ons.

Slow down with the drilling. Step away from the power tools. Thanks guys- you scared me into finding a solution.

Found it-
they call it a clamp on Front derailleur cable stop. Didn't know that Suntour superbe pro made 2 versions, one with the cable stop and one without.
Naturally the one without a cable stop is more available. On lots of 70's-80's bikes they have above bracket cable routing.
this bike has a brazed on routing guide- https://phred.org/~alex/pictures/bikes/trekroad/bb2.jpg

If you have a 1-1/8" down tube you can buy a New Old Stock Campagnolo 626a clip. You shouldn't have to spend this much, there are plenty out there so some detective work will get you one at a reasonable price.

Otherwise, you can drill and tap (or pop-rivet) the bottom for the BB shell for a screw on guide in plastic or metal.

Hey, glad to be of service in the scaring department. Just that I figure the extra piece of housing tucked up against a stop that's clamped and cantilevered creates an additional stress point on the seat tube in the BB area. Just want to reduce that to protect the frame and having cable housing facing up from the BB in a curve is sort of like a water trap, unless it's an unsheathed cable housing like on venerable Suntour barcons that air-dry and drain. I'd grease the heck out of that cable and housing and replace it regularly on routine maintenance.

On the other hand, the under-the-BB solution works well, requires no braze-ons above the BB and is serviceable with no extended stress-bearing members. The derailleur cables actually keep the cable guide pressed up against the BB. And I have a drill and tap, which is why it'd be my favoured solution. So I have a hammer ... everything looks like a nail.

Back before plastic guides were available, we'd just file a channel into the shell for the cable to follow. Too much work these days. Why not simply glue the plastic guide to the shell? It doesn't need to be a particularly strong glue, as cable tension will hold the guide in place.

+1 on glue or double sided tape to hold the guide in place. I've even heard of mechanics who just placed the guide with no fastening at all and the cable tension alone was enough.

Yes, those of us who "invented" under the BB routing 40 or so years ago, improvised many solutions using filed, groves, plastic or model airplane tubing, or nothing at all for FD under the BB routing.

RD routing was more of a problem for 2 reasons. The most important issue is that many of our frames had brazed-on chainstay stops on top of the stay, and so wanted the cable routed above the shell to run clear. Some creatively run it under the BB, and did a half twist coming around the inside of the right chainstay, but it was less than ideal.

If the OP has a clip on chainstay stop, under the BB routing is easy, but if he has braze on above the stay and wants to use it, the 626a, or comparable clip is the best answer.

BTW- I stopped recommending simply looping the wires below the BB without a clip, because it was too declasse for many on this forum, and folks would worry about the wire sawing through the paint (that takes 5-10 years, or more).

10 dollar holler.

https://www.amazon.com/dp/B004FSVVN8/...ackoverfl08-20

You can just also run the cable under the BB and use a clamp or cable stop above the BB.

Drill a hole, and put a plastic one at the bottom of the shell, done.