Last year while hiking over Taboose Pass I managed to wear out and break the pole tips on my Leki trekking poles. I am not sure how many miles these saw, but I think most of the Colorado 14ers as well as a Sierra Challenge and some big day hikes. In any case they were not always easy miles. On this page I show how I replaced them.
Step one - get replacement pole tips. You can order them online or buy them in a store if you can find them.
Step two - remove the old tips. I did this by sticking them in boiling water to soften the glue and then sticking some loosened vice grips between the pole and the tips, stepping through the pole strap, and then hitting the bottom of the pliers with a hammer. There might be better ways of doing this, but it worked for me.
Step three - clean any lumps of glue and rocks off the old pole ends and stick the new ends on. Then pound them down onto something (I used an old board) to seat them. You should be good to go.