Bottle cage rivnut replacement.

As my frame of my Sonder fatbike is carbon the bottle mounts are inserts, called rivnuts, that fit into the frame like rivets. The supplied ones are aluminium, fine until a bolt decides to seize and shear off the lower part of the rivnut inside the frame, so the bolt just spins in the hole trapping the bottle cage in place.

The solution was to cut the bolt off using a junior hacksaw, then drill out the rivnut starting with a drill slightly larger than the remaining hole then working up the sizes half a mill at a time until the rivnut popped out. I managed this without damaging the carbon frame;

I can't fit rivnuts myself so I took the bike down to my local bike shop, a two minute job for which I was charged a couple of quid;

This apparently is a common problem on carbon bikes, sometimes needing a larger rivnut.

Once this was sorted I attached a Topeak Alt-Position Cage Mount, which has allowed me to move the bottle cage further down the frame so that when my frame bag is fitted and I'm carrying a water bottle the top of the bottle doesn't foul the bag.

Its shown with a Monkii cage fitted, the velcro strap means that I can carry a travel mug of tea (which wouldn't fit a normal cage) or a water bottle.

Paul.