The KDI brass spiral is very strong. You may need to do a little filing on it with some small files. I have it on 2 of my regular riders.

It comes with instructions. The brass spiral must be oriented exactly as the nylon one is. Push it straight on using a vice.

 

 

 

 

Yes i guess the brass one needs to be about exact pressed on or arm could be way off up or down. Depends if your case external spiral is ok too but i don't think they give up or not that i've seen.
How are they kept from moving or is there a rough bit under the original that you press it over to bite on it.

I put mine in my wood working vise and pressed it in…
Orientation is key… KDI has a picture in the instructions for that….
Sneezles61

RT325 said:
How are they kept from moving or is there a rough bit under the original that you press it over to bite on it.


The center of the actuator has splines that grip the inside of the brass spiral as well as the original nylon. Since the brass is much stronger its less likely to move. These should make it good for another 50 years.

Also you need an actuator that is in overall good condition to start with. I've seen them mangled up after a chain derailment.

I wonder if mine had such a moment… the was some welding that occurred.. I didn’t see it from the outside, but once I cleaned the underside…
Sneezles61

thats perfect that you included pictures. thank you! I will double check to ensure the rest of the housing is in good shape.