While working on my K5SM (KX500 Supermoto) project I ran into a problem with a threaded insert that holds the sub frame onto the main frame.
The previous owner had stripped the threaded insert that is welded to the frame and he used a Heli-Coil to fix it without drilling it out and using a Heli-Coil of the correct size.
Here is the threaded insert that is stripped:
I could get the correct nut size, grind the old nut off and weld a new nut on.
Since the frame is powder coated I wanted to save the powder coating.
To the right is the Heli-Coil that was used to fix the problem.
To the left was the EZ-Lok I was going to use to fix the problem.
Unfortunately the EZ-Lok was too large and I would ruin the threaded insert if I tried to use:
For him I'm sure that the Heli-Coil was fine as he just wanted to ride the bike and didn't care what size bolt it took to get him going again.
However, I could not use the stock bolt with the Heli-Coil and I want to use the stock bolt:
So, I decided to fix the problem by welding up the the threaded insert and then drilling it and tapping it to the correct size.
In this case it is M8 x 1.25.
Knowing that the weld material is by far harder then the insert material I decided to give myself a small advantage by making a small plug from a bolt and welding that to the bottom of the hole.
Doing this allows me to get a pilot hole started easier in the softer material of the plug.
I took a small fastener and ground the edges off the head so the the head fit into the stripped out insert:
Once I verified that the plug fit into the threaded insert I cut off the threaded part of the plug so that I was left with a stripped out head.
Next I held the plug into the end of the threaded insert that I was going to drill and tap into.
Again, I wanted softer material to drill into to begin with.
