How to Size and Install Shift Cable Housing

properly sized and routed shift cable housing can make a huge difference in your bike's performance in this video we will walk through the process of sizing routing and installing new shift housing on your bike [Music] in mechanical shifting systems the cable pulls or releases a set amount of cable to cause the derailleur to move a set amount if the cable or housing has become kinked worn frayed or corroded you may experience slow shifting inconsistent shifting hard shifting or no shifting at all this video will focus on housing replacement for shift cable replacement see our playlist here [Music] typical tools and supplies include a bicycle style cable and housing cutter like the cn-10 a pick set like the upset from park tool light lubricant internal routing tool like the ir 1.2 [Music] zip ties appropriate housing ferrules also known as end caps cable ends a flashlight and a tool for crimping [Music] there are three different routing types full housing segmented housing and internally routed housing let's take a closer look at each and the parts that make them up full housing is when the housing runs all the way from the shifter to the derailleur uninterrupted segmented housing is when there is a stop in line where the cable will be left open for a set amount of distance internal routing is when the housing is routed internally in the frame and or other components and can be either segmented style housing or full housing in addition to how it's routed there are different types of housing as well as different sizes this is a cutaway example of brake housing that is wrapped like a spring this allows the housing to compress slightly and for that reason should not be used for shift housing this is shift housing it is also known as compressionless housing if used for breaks it will bow and blow out under high pressure it is wound more longitudinally to better resist compression this is what we want for shift housing this is a braided version that can be used for either break or shift housing due to the metal or kevlar braid reinforcing the longitudinal strands of the housing this is typically found in an aftermarket high end housing system there are also link style housings that are comprised of many small links or beads that will not compress or blow out and allow for tight bends housing comes in two common diameters five millimeter housing or four millimeter housing five millimeter used to be very common and is more rigid and resistant to bending it will typically have a larger inner diameter giving the cable inside more wiggle room currently four millimeter is the most common housing size for shift housing and is what we will be using throughout this video on the ends of the housings are ferrules or end caps ferrules keep the housing contained and prevent it from deforming or digging into the frame cable stops and other bike components if a ferrule fits in the component it improves the shifting if it doesn't fit the component is already sized for the housing as it is in this case do not use a ferrule ferrules are commonly made of metal or plastic no matter the material or size of the ferrule they need to be properly installed fully seated over the cable ends and then properly seated into the cable stops or other components a housing component you may encounter is an inline barrel adjuster these are used to allow the derailleur indexing to be more easily adjusted typically found on front derailleurs the final piece of your cable housing system is the cable end cap end cap keeps the strands of the cable in one nice tight bundle and are then crimped on [Music] when determining housing length you want the housing to be as short as practical while feeding straight into the cable stops if your bike has previously routed housing you can inspect the length to determine if you can use it as a template and run the same length again however if you see damage to the housing end caps or frame of the bike these are all signs of improper routing or length in a worn out cable system notice here how this housing is kinked and this housing is worn through the housing has even worn through the paint on the framer components and this housing is too short this end cap is cracked these types of problems can be remedied by either changing the housing length or potentially by improving the routing you'll also want to consider the future changes to the bike like handlebar height stem length or handlebar width be sure to leave the housing longer if you see something like that happening in the future when installing full housing it's best to start at the back of the bike it also can help to install zip ties at each mounting location as you go forward to help keep things in place especially if you are routing more than one item on the same mounting tab starting from the back feed a long piece of housing up through all the zip ties that you just put in place do not tighten the zip ties as you go so that the housing can freely flow through them be mindful of kinking or pulling if installing on a full suspension bike while the bike is going through its travel the cable could become kinked or pulled once you reach the head tube of the bike you are often faced with the option of going around the left or the right opposite the shifter will typically give the most gradual bend in some cases that is simply not possible and exiting the same side as the shifter is necessary feeding the housing up to the shifter you want the sweep of the housing to be gradual have enough free range to turn road bars about 90 degrees or mountain bike bars as far as they will go if interrupted or 180 degrees if uninterrupted road shifters sometimes have options for running the housing in front behind or out the side these options can affect how your hand sits on the bar and how direct the housing is routed check that the sweep of the housing is gradual again you want the housing to enter the stop in a straight line if working with drop bars tape down your housing with your rough housing ran tighten your zip ties down now to size the housing at the back of the bike derailleurs have two main housing exit points either out the back or out the top in the front for housing exiting the back make a sweeping curve and pull it tight you want the housing to feed in as straight as possible if the curve is too tight the cable can kink and if it's too large it can kink in the opposite direction again you want the housing to feed in as straight as possible use a cable cutter like the cn10 to cut the housing when you cut the ends of the housing it often crushes slightly and the liner is deformed use a pick or awl to open the liner up now install a ferrule on both ends push the cable into place note that some shifters do not require ferrules for a segmented housing start from the rear of the bike and install one end of the long section of the housing into the rear derailleur loop the housing forward to the housing stop at the frame you want the housing to feed in as straight as possible watch the ferrule for alignment if the curve is too tight the cable can kink and if it is too large it can kink in the opposite direction we are looking for goldilocks and a bend like this is just right using your cn10 cut the housing open up the ends of the housing with a pick or an awl install ferrules on the ends of the housing install your cut segment of housing into the housing stop and rear derailleur since this system is segmented we need to locate our next housing stop some are routed below and some above the triangle of the bike follow the cable's routing and find your next section install one end of your long length of housing into the housing stop pull and push the housing at the stops to find a good curve in the housing goldilocks cut the housing with your cn tent open the end with a pick and install the ferrule install your cut segment of housing into the housing stops at the front of the bike we are faced with many of the same issues that we saw for full housing you can often choose the side of the head tube the housing exits this may require the cables crossing under the down tube or top tube exposed cables lightly touching one another is fine cables hitting the frame is not okay install the housing in the stop at or near the head tube route the housing up to the shifter giving it a nice gradual sweep if you are working on drop bars and have a front and rear derailleur the housings will be the same length pair the two housings up and cut to match this gives them a nice exact matching appearance cut the housing and install the ferrules as needed internal routing can be proprietary on some bikes this is going to be an overview on how to internally route as well as skills that are typically needed for more on your bike specifically please reach out to your manufacturer internal routing is often full housing but can also be segmented there are also sleeved internal systems that allow you to push the housing in one end and it just pops out the other end for systems that are not sleeved it is very helpful to attach either the threaded end of the ir 1.2 to the original housing or a coupler like this to the original housing to pull the new housing through if there is no housing to start with use the ir 1.2 to route the housing through the frame see this other video for a more detailed look at the ir 1.2 start by routing the ir 1.2's wire through the frame or component with the magnet attach the wire to the housing by turning the tapered section into the housing you can now carefully feed the housing into the bike while softly pulling do not pull too hard as you may pull the thread out of the housing if you encounter resistance pull back on the housing slightly this re-situates the housing inside to avoid the obstruction that was stopping it do this until it passes once you are past any obstructions the housing will come out the end or it may get stopped and you'll need to pull it out with a pick it's time to install the cable in the housing these other videos will walk you through installing the cable into the shifter once installed in the shifter it needs to be routed through the housing for full housing simply start feeding the cable into the housing as you feed the cable in add a light coating of lubricant to the cable a big reason to do this is to prevent water and dust from getting in be sure not to force it and to stop pushing if you feel any resistance if resistance is felt the cable may be coming out of a junction or maybe trying to make a bend if at the end of the housing or attempting to come out of a junction it helps to remove that section straighten it out and allow the cable to come through then reinstall if it is resistance at a bend that is being felt it can help to roll or rotate the cable as you push if the housing is segmented you will push the cable through the different segments in open areas some people will run cable donuts these cable donuts aid in reducing any rattling that the cable may cause the cable is now out at the derailleur and needing to be installed and adjusted once you get the cable connected to the derailleur and able to be shifted hold the rear derailleur with your left hand and actuate the shifter with your right hand this will help seat the housing into the ferrules as well as do a little bit of a pre-stress on the system you may notice after doing this that your adjustments need to be revisited and completely reset with your cables installed all that's left is setting up your front rear derailleurs and for more on that head over to our derailleur playlist here thanks for routing with us and we'll see you next time [Music]

Channel: Park Tool

Views: 154,889

Keywords: Bikes, Bike Maintenance, Bike Repair, Bicycles, Bicycle Maintenance, Bicycle Repair, Bike Tools, Bicycle Tools

Id: Mq-WAze1F_Q

Length: 14min 12sec (852 seconds)

Published: Fri Jun 17 2022