I just installed a used rear derailleur to my road bike with cables and housings and all.
I am having some difficulty in getting a good position on it.
My 1st question is regarding cable housing. How long should I cut it? is there some formula? Does it not matter at all?
The main problem I am having is that the 1st 2 or maybe 3 clicks of the shift lever dont seem to move the pulley from the small cog. Of course as a result it does not make it up all the large cogs.
I have watched dozens of online videos and yes I read the park tool website and the sheldon guys page on RD, but still need some pointers.
I assume your cable question is for the last stretch of cable ending at the derailleur. This should have a nice relaxed loop so that the cable does not bind. For most RDs ( Rapid Rise is an exception) the movement up the cogs from small to large is pulling on the cable and making it tighter, so problems with this direction would indicate a cable that is too loose. Go back to the small cog, make sure your stop screw is set to center the RD on the cog, and get the cable good and tight. Then click up. Re tighten with the cable adjuster if needed.
Going in reverse, when there is a problem going from large to small cogs, the problem is a cable that is too tight, so you loosen to get the RD to move away from the wheel. As you can see, you will need to be between too tight and too loose. You also need both stop screws set to line up with the cogs at each end.
Look at this photo. As you can see, the red cable-housing makes a gentle curve to guide the cable from the stay into the rear-derailleur. This is done so the cable won't get bent - which would cause it to malfunction.
Originally Posted by Cateye
Only panthers007 is stupid enough to believe that this is a good idea.