Originally Posted by
oceantin
I have a really stupid question. I have seen the term "cable ratchet" many times in this thread. I really want to know what exactly is cable ratchet? Is it the shift cable housing that come out horizontally from the brifter? Do i have to take the cable out or just the cable housing out in order to blast WD-40? How can i take the cable or cable housing out from the brifter??
Also, if you blast WD-40 and then lube to the cable ratchet, the brifter will be filled with those liquid. Will those WD-40 and lube go down to the bar tape? and soak the bar tape?? Or i have to take the brifter out from the bike before i do that?
I know these are really basic. I as well have a RSX 7-speed drivetrain that i may need to service later.
Thanks!!
THe term "ratchet" generally refers to something that turnd freely in one direction but has limited or blocked motion in the other - like a "ratchet" socket set that can tighten a bolt in one direction and spin freely in the other to put the wrench in position to tighten the bolt some more.
I believe the "cable ratchet" people are talking about is the internal mechanism in the shifter that can be twisted with the large lever to pull cable in, and does not allow cable to slip back out until you use the small lever to release the mechanism by one click.
Lubing the cable ratchet is probably best done by pulling the brake lever toward the bars (or to where the bars would be if the shifter is not on the bars) and look inside for a mechanism made up of small parts and springs and such. THe grease in this mechanism is notorious for hardening and making the mechanism malfunction after several years, and some WD40 or degreaser in this mechanism can help thin it out and get the shifters working again. Since the mechanism is not well sealed, any fluid sprayed in will simply run out the bottom... the stuff that doesn't will eventually evaporate.