Bars Kept Slipping On Stem

the knurling on your bars might be gone.

Make sure you're tightening the stem in an X pattern. Also check the knurling as Travis said and make sure the paint isn't causing it by being too thick where the bars & stem meet.


Another thing might be the stem is stripping out where the bolts go or even cracked somewhere and not holding like it used to, so check that. Check the bars too and make sure they aren't crushed too, that could cause slipping.


If it's none of those things, it might just be time for a new stem. Or if you're feeling bold you could take a hacksaw and very lightly saw some grooves into the handlebars to help it hold better, do that as a last resort though.