If you can’t fit new rivnuts ( unlikely in composites ) or if they are molded in inserts:
Take the inserts off the bolts, assure the insert and the hole they left are dead clean. Lightly grease the threads of the bolts and reassemble everything onto the mount. Epoxy the whole thing back into place on the bars assuring the adhesive doesn’t get on the mount itself or the bolts, only the inserts and bars get adhesive. By gluing the whole assembly in place you should maintain correct alignment of all components. Fixture everything in place so it doesn’t move until cured, work out how you’ll hold it until it sets up before you apply the adhesive! The grease on the bolts should allow the mount to be removed normally once everything is cured.
use only freshly opened quality adhesive. use two part epoxy. Not the 3 minute kind, that gives up some finished strength for speed of cure. The good stuff takes up to 24 hours to reach full cure / full strength, be patient and wait the full amount. Loctite and Henkel brands are your friends.
don’t use superglue ( cyanoacrylate ) Unless you know how to use the stuff it’s more trouble than it’s worth.
In the past I’ve recovered threads and inserts retaining motorcycle handlebars, tooling on industrial robots and a number of other fairly high demand items. I even did a brake line mount on a carbon mountain bike last summer.
yup, spent eight years researching and specifying adhesives for automotive applications, it’s about time it did some good.
