There is at least one "off" brand of twist grip shifter that the cable is not replaceable. Don't remember the labeled brand but do remember being frustrated by this a couple of times in the last year. Kind of sucks when you quote a service with only the cost of a cable replacement and have to call the customer back with a redo at the higher cost of a quality SRAM MRX replacement. Since these poorly designed twist grip shifters come on the cheap bikes the customer is often far more price sensitive, one has to make the phone call. Andy.