Originally Posted by
TKJava
I took my bike in to the LBS yesterday to discuss getting the derailleurs adjusted as I am getting some chain rub on the inside of the front derailleur cage. Basically my chain rubs when I press hard with the left foot. This as I understand it can be a simple adjustment of how far the cage moves to the outside when shifting into the large chain ring. I also mentioned some less than smooth shifting in the rear. After about 15 seconds of shifting the bike the LBS mechanic says "you need to replace the shifter cable from the hoods to the rear derailleur, these often get twisted inside the tubing" (I have internal cables). He also said that over time the end of the cable can simply break off inside the hood when they are "too old". This sounds a bit flaky to me. Under what circumstances can a cable a) get twisted and b) why would replacing it cure that?
While the issue you are having may or may not have to do with the condition of your cables/housing, the mechanic may have determined that the condition was poor and dis not want to get into trying to tune a bike with bad cables.
Although a simple cable tension adjustment might have been all thats needed for the front, the rear may have required more work.
Or maybe his rent was coming due and things were slow at the shop.