October 17, 2012

Gravel Bike - Part 9

Part 1

I installed the brakes in Part 8, now they needed cables.  I ordered the standard SRAM brake and shift cables.  There are some very cool sealed cables available, but they were so expensive it seemed like I could replace these cheaper cables a couple of times before paying for the expensive ones.  The brake and shift cables are not interchangeable.  The SRAM boxes were labeled appropriately.  It seems like it would be impossible to confuse the two since they have different outer sheaths and different inner cable diameters.

The inner cables go through the shifter handles once the rubber covers are peeled up to expose the entrance hole and exit groove.

The outer sheath is threaded over the inner all the way up to the shifter and inserted up to the stops.

The other end of the cable has to be cut to fit.  It will be different for every bike.  I just set the cable into the stops with some nice easy smooth bends.  Then I came back and used electrical tape to ‘tie down’ the cable to the handlebar bends.  Next I swung the handlebar from side to side through the full steering range making sure there is no interference with other parts, while also checking to make sure it didn’t pull too tight or limit the steering range.

I have a great tool for cutting cables.  It is the Park Tools Professional Cable Cutter
It does a great job of cutting the outer sheaths without crushing the anti-compression windings or the inner Teflon liners in them.  The first bike I built I used a Dremel tool with a cut-off wheel for the cables.  It worked, but not very well.  Do yourself a favor and get this tool (or borrow mine) before your next cable job.

I continued routing and cutting the sheath until I had the length right.  I stuck a ferrule over the end and seated it in the brake caliper.  The BB-7 caliper has a nice seal over the outer sheath and inner cable end to keep out water and grit.
 The interior cable is pulled tight and clamped down under the caliper cap head screw.  I didn't have a torque value for this so I just got it nice and tight without going crazy and crushing the cable.

I cut the cable off leaving about two inches hanging free below the caliper.

Lastly I secured it with a nice red anodized aluminum end stop.  The same Park tool I used above has a die set to crimp cable ends also.  It comes out looking way better than mashing them to hell with a vice-grip.  I hate it when bike don’t have these cable ends on them.  The cables end up frayed in no time making any further maintenance on them almost impossible.

I used the same methods to install the front brake cable and shifter/derailer cable.  It takes all the same steps so I didn’t take a bunch of extra pictures.  Here is a great link for everything you ever wanted to know about bicycle cables:  Sheldon Brown

The bike is getting really close now.  I want to take it out for a test ride so bad.  Just waiting for tires to show up, then I put in a seat post, saddle, and ride!

Part 8                                                                                                                                  Part 10

1 comment:

  1. I have that tool also. I bought it when I was installing the rudder on my kayak.