Originally Posted by
seedsbelize
My stupid question concerns barrel adjusters. As far as I can tell, all they adjust is the cable housing, and how this a(e)ffects cable tension is beyond me. I know that it does, but I don't understand how. Can anyone clear this up for me?
Ah, barrel adjusters are usually used for adjusting barrels.
Okay, the key feature of a cable is not the length of either the cable or the housing, but rather the difference between the two. When you turn a barrel adjuster so as to tighten a brake, for example, you are increasing the effective length of the housing by moving the housing end further from the lever. What this really does is makes the housing take up more cable so the cable becomes effectively shorter, which is to say shorter w.r.t. the housing. The actual cable length doesn't change but it becomes shorter compared to the housing because the housing gets longer.