TCU bolt cross threaded

[Vado London]

For some reason the torx bolt that holds the TCU on top tube will not undo. It seems the thread has stripped and the bolt just turns.
Any thoughts on how to remove without breaking the casing ?
I don’t think a bike shop will be able to fix.

 

[rich c]

What's a TCU?

 

[Alvin1957]

Hey there. Used to work in machine shop and hit similar problems. If you can get at the end of the bolt (if it passes all the way through the threaded female part), apply pressure to end of bolt (as though trying to push it back out) and turn counterclockwise (to loosen) VERY slowly. Sometimes you can get the thread to re-engage and start the bolt moving back. Alternately, if you can get a very small pin-vise or drill and bit, drill a small hole into the end where you afix the torx wrench/allen wrench. Next, use a very small 'easy out' or screw extractor to pull and turn to get the thread to re-engage. If thread is really buggered up inside, a local machine shop can almost certainly pull it in about 10 minutes. Better set up and tools suited to this than LBS and hardware stores.

 

[Vado London]

Hi Alvin
Really helpful. I shall carry out all your suggestions and update here.
thanks again!