Best glue for shoe repair?

There’s a minor bit of separation between the sole and the toe cap. I want to keep it from getting worse. tx

Barge Cement red and yellow. It's the closest thing you're going to easily find that matches production glue.

Do:
-clean the area
-coat each side lightly
-longer you wait the better the bond inside of that 4 hrs
-some heat always helps
-press that mf'er

Barge Cement used to be the gold standard until they stopped using toluene(glue sniffers and all).  It's still pretty good.  As with any contact cement you need to clamp the two parts together after gluing to get maximum bonding strength.

Don't use shoe goo, it's poo poo for climbing shoes.

STR cold bond adhesives work really well, although it's primarily used for conveyor belts. I've repaired several pairs of shoes with it.

When I resoled my shoes many years ago, I used Barge cement. We heard that professional resolers used it. So, that is the safest bet. The glue stinks though.
One has to clean the area well, apply the cement to both surfaces, wait for the recommended time, then clamp. I put my shoe under a car tire, and parked on top of the shoe overnight.

Though I haven't tried it for shoe repair, I have recently found that of all the glues I tried (including specialty rubber glues) the strongest bond for high-density neoprene rubber was superglue, hands down. In that case, I was gluing the rubber to wood. But the bond has held up for the past year of daily use on some hand-grips I made to work out with. At least in that case, the bond itself is stronger than the tensile strength of the rubber.

One can release both a barge bond and a superglue bond with applied heat. So, if one makes a mistake, it is possible to redo.

not for climbing shoes but general shoe repair  if you are a carpenter.PL200 works fairly well. 

Nolan Yahok wrote:

What superglue are you using? Mine always ends up super freaking hard

Good point- in my application I wouldn't have noticed the hardness. It might be worth trying if one is just patching a small bit, but, as I said, the barge would be safest. 

Anyway, for superglue, I prefer the stuff in my local hardware store by FastCap called "2P-10 Professional Wood Formula". lt takes about 30 seconds to cure and comes in a 64-g bottle but lasts long even after opening (I've been using the same bottle for a year.)