Cable Routing: Is Yours Done Right?
There is something I have noticed on a lot of bikes that is often overlooked. You can see it on random bikes at the trail head, your buddies bikes, or even your own. It can even be seen on brand new bikes sitting on the show room floor. I am talking about cable routing. A lot of the time how and where you route your cables and housing sounds as if it is such a simple and inconsequential thing. I want to outline why it matters, and how it will make your bike ride better for longer.
The reason for so many riders over looking how they route their cables is that it is hard to see how it makes your ride better. By having everything routed properly, you will have much more precise shifting, less ghost shifting, and potentially less wear and tear on your bike and components over the long haul. I’d like to help everyone understand why the proper length of housing is so important and I want to give you all a few tips that I have discovered for a good clean and functional set up.
The length of cable housing is the first issue, and hopefully I can explain why it is important. It’s possible for housing to be too long as well as too short. Both of these situations can negatively effect the quality of your ride.
It is very often that you will see cables and housing that are left significantly too long. Often times this is not the fault of any mechanic or bicycle owner, many stock box bikes (non custom builds) come with the cables already installed. In a factory that churns out several hundred bikes a day, they will tend to only cut one length of housing and let that be used on every size frame. Because of this, you can end up with a small bike with cables and housing designed to be run on an extra large frame. While everything will still work “well enough” and be functional, it is not an optimal set up. When you have anything that is too long, the likelihood that something will get snagged or caught is greatly increased. You can also end up with slower shifting due to excessive housing creating more friction on your cables.
On the flip side of this coin, it is important to not have housing that is too short. Short housing can limit the range of motion in either derailleurs, brakes or steering. If for any reason a derailleur can not swing properly, shifting can be vague and will be inconsistent. You can also end up in a situation in which when going around sharp corners turned the handle bars will add extra tension to cable brakes or derailleurs causing your bike to shift unexpectedly or it could even cause a brake to lock up.
Now that I have told you what is so bad about too long and too short housing, I imagine I should give you a few tips for proper set up. It most cases turning the handle bars to be just past parallel with the top tube gives an idea of the proper length. In most cases you would never turn the bars past this point , or even to this point during a ride. In some mountain bike builds you may turn the bars around a full 180 degrees just to leave a tiny bit of extra slack in the line in the event of a crash. This will prevent housing from being pulled or broken post crash and you can still finish your ride.
Once you have the bike in this position you can put one end of the housing into the shifter and then lead it to your next housing stop (or housing mount on full length housing setups) leaving just enough slack to get to this position. Now it just becomes a matter of running bits of housing the rest of the way down your bike. You want to leave enough slack around derailleurs and brakes so moving parts have a full range of motion and that there are not sharp curves or kinks in the line. Full length housing can be a tad trickier to measure. It’s usually best to mount up the housing as you go (use zip ties or an other form of cable guide) and trim off the excess.
Now that you know how to measure your housing, it is important to figure out the proper placement and order of your cables and housing. Running cables to the inside of your frame and fork is something that is so often over looked. By routing everything to the inside you tuck away your hydraulic hoses, and any other potential twig grabbers so that nothing gets yanked, pulled, or twisted. If you have ever cut a hydraulic line mid ride before, you know how catastrophic it can be.
The order of your cables is also rather important. On most mountain bikes, your front brake would usually go the furthest in front. Your front brake housing is static and will not be affected by steering input. By having this one all the way in front it should never pull or push on any of the other cables. Next in line would generally be the rear brake. The rear brake (when mounted on the right side) will generally have to come across your head tube and run down the left side of your bike. Because of the housing running across the front of your bike it is typically going to be a tad longer than your derailleur housing which is why you would want to have it in front of your derailleurs. Once again this is to prevent any pushing or pulling on any other cables. For people that run their brakes “moto style” (rear brake on the left side) you do not have to worry about running the brake across the head tube and would just run it straight down the left side of your frame. You would still however want to make sure you cut everything to leave enough slack to move your bars freely. Lastly and closest to the rider, front to rear, you run your derailleur cables. The proper routing is completely dependent on your frame and how the frame is designed. For a cleaner look, a lot of bikes work well running your derailleur cable down the same side of the bike that the shifter is located on. This allows for you to use a little less housing and still keep things tucked up and clean. There are some bikes out there that have the derailleur housing running to the opposite side of the frame, the problem with this is that you will have to at some point cross the cables to allow your rear shifter to meet up with the rear derailleur. Crossing the cables can look really cool and presentable, however, if not done properly it can add a lot of friction.
So now that you have a couple of tips and pointers, you can start working towards a more pro looking, and functioning set up on your steed. You can also appreciate some of the long term benefits. You will not have to replace cables and housing as often and hopefully you can avoid any busted hydraulic lines allowing you to spend more time on the trail and less time wrenching. You can also keep your frame looking better because the proper length of housing is less likely to rub the paint off of your bike. Frame wear still can happen, however, you will be more prepared to address the issue so it does not keep rubbing in the same area. Hopefully if you made it all the way to the end of this post, you will find these tips to be helpful in the future, and can get your bike ready to roll smoother than ever on your next adventure.