So I'm trying to route new brake cable (thanks to everyone who's helped so far, and have run into a question I don't know how to deal with. On my bike the cable guide at the seatpost end of the top tube is an inch or two long and bends around the seatpost and down to where the cantilevers are.
Because of the bend, I'd been under the impression that there should be some sort of housing to smooth the passage of the cable through that guide. The full cable housing doesn't fit. On the previous cable, there was some worn out something (tubing or something) around the cable, but I dont' know exactly what it was. Any help with what I should put around the cable as it goes through this bendy guide or is nothing necessary? Thanks so much.