Below is Michael Selmans reply.
Mike,
The manufacturer insists that their wire is significantly stronger than stock. They suspect that the two cables that they repaired for me so far were prematurely worn-out because of mis-aligned cable adjusters.
I'm not suggesting that this is the fault in your case, but if the slot in the threaded adjuster is lined-up with the slot in the jam nut, then the cable can chaff. There also should be about 1/8" of free play in the lever.
Michael Selman
