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Discussion Starter · #1 · (Edited)
I was thinking about stuff while riding this past weekend and kept coming back to cable/hose routing. I do mine "properly" but want to understand the thinking behind those who do it wrong. At minimum this should be fun and there is a very slim chance that someone will convince me that I should start doing my cable routing the wrong way. It also may serve the community by getting the wrong headed people on the path to enlightenment so we can get an industry standard for cable routing.

To get started, let's define the right ways. Ideally this will lead to an argument so please jump in and engage if you disagree with what I deem as "OPTIMAL", "SUB-OPTIMAL", or "WRONG".

OPTIMAL:
With a proper seat stay style brake mount the rear brake hose is attached to the underside of the top tube. The hose guides are 60mm away from the head tube and 60mm away from the seat tube. The middle guide is exactly in the middle of the span between the other two guides. Two guides route the cable down the underside of the non-drive seat stay where it can reach the rear brake. Gears cables should also be routed on the underside of the top tube if the bike is built to use them.

SUB-OPTIMAL:
If the bike is built with a less proper chain stay style brake mount cable routing should be on the top of the down tube followed by the underside of the non drive chain stay. The guides should 60mm from the ends of the tube with the middle guide in the middle. For most bikes two guides should be enough on the chain stay.

WRONG:
Any guides that are on the top of the top tube, top of the seat stay, or even top of the chain stay are wrong. These guides seem so wrong it is hard to imagine why anyone would do it this way.

My thinking:
On a mountain bike, delicate body parts may slide along the top of the top tube in a dismount or crash. Having a cable or a guide there is not good. The cable on the top of the seat stay is somewhat ugly and if something is caught in the wheel it can be pulled into the cable and possibly snap the zip tie or snag on the cable and create a problem. The down tube cable routing is sub optimal because in a log or rock crossing you could get your cable in trouble. It is also pretty ugly (subjective) so really for chain stay mounted brakes internal cable routing is the best approach although really with hydro internal cables seem like a PITA.

In any case, it's a good subject to argue about and it would be interesting to hear the thoughts of other builders and/or riders. Some of you must like these evil top side cable guides and it would be interesting to hear the thinking behind that approach.
 

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Meh, it just depends. Want a frame bag in there? Like to shoulder the bike? Have a curved tube and don't want a bowstring effect? Prefer internal routing? Electronic (it's coming, ugh) shifting?

It's just a case-by-case thing. Be creative and do whatever you think works best.

Edit: I will make one exception: early 90s side-of-the-toptube routing is awful. There is no reason I can think of to do it, but it was pretty common for a couple of years.

-Walt
 

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I agree with Walt... appropriate cable routing depends entirely on the bike and how it will be used.

I personally like full length housing for mtb frames so I avoid using stops when possible and stick to simple guides. I also dislike 'race cut' cables on most frames, so I don't like being forced to route shifter housing on the same side of the HT.

If cables are routed internally there should be a full length sleeve/guide absolutely every time. I've spent plenty of time fishing cables as a mechanic that I won't impose that on another.

edit: Also- eliminate zip ties wherever possible and reasonable.
 

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I would take it on a bike-by-bike basis and run the housing in the smoothest manner possible. I think a lot would depend on the bike size and construction, and the particular components involved. I never shoulder a bike, and I frequently rest a leg or butt cheek on my tt, so I would never route anything on top of my top tube. For a cable and housing, I would put housing stops on the bottom of the top tube, offset to the non-drive side to ease the bends at either end and to reduce frame contact with the housing, but keep them tucked in enough that I cannot see them from above. For a hydro line, I would run it at 6 o'clock on the tt since they are bulkier. The bike I just built has a hydro line on top of the non-drive seat stay because that was the smoothest routing. It would have had some tough bends if I had routed it on the bottom of the seat stay. Maybe different brakes would have changed that, but with what I had that was the smoothest route.
 

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I think I'm quitting internal routing. I got a nice core sample out of my palm setting it up on this latest frame, and as far as I can tell it makes the frame weaker and reduces functionality. Maybe I'm just grumpy though. I don't like calling things "right" or "wrong" because they are all different. I try to avoid hoses and stuff under the DT though because I am scared of them getting smooshed by rocks and stuff.
 

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Interesting Topic.

I agree with Walt, but will add the following:

Some completed bikes that I have seen have been poorly 'fitted' as far as cable lengths are concerned. By this, I refer to say an XS sized bike using off the shelf length cable that has an extreme surplus overhanging the handle-bar end of the bike compared to a XL size where the same length cable looks more flowing. Cables need trimmed up and fitted well.

I built a frame once that the owner took to a bike shop who fitted cables off the shelf and made an ugly hash of the job. I took the bike back one Saturday morning and redid the cables in front of the mechanic who argued the whole way. It comes down to attitude sometimes. And some people don't think this process through. And others don't see it as an area of pride and workmanship.

Eric
 

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Getting the cable length right so nothing pulls and so the housing curves nicely does appear to be challenging for many mechanics. Do you think this has anything to do with the kind of bike people grew up with? I grew up on road bikes, and style was always a concern with roadies (at least then) and I carried over the attention to detail to mountain bikes.

Although, a lot of the work I saw during my time in bike shops appeared to be the result of laziness, not necessarily a lack of attention. Eric - I wonder if that shop guy that protested about your cable re-do had his own bike cables nicely routed.
 

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Ride Bike

The young mechanic guy has recently come back from the Track World's with a Bronze around his neck, but then are no cables on a track bike!!!! The shop owner and friend was once my apprentice, so he sat back amused when I did it.

Eric
 

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I'm in the case-by-case camp. I think the main thing is that you give it the proper thought for each frame. Am I right in thinking that the front derailleur will dictate the cable routing? Take the frame I am working on right now: I am using a SRAM X9 front derailleur that is clearly a top-pull only model. Therefore, I have no choice but to route the cable along the top tube, correct? Likewise, if I was using a bottom-pull FD, I would need to route the cable along the down tube and under the BB, yes?
 

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Why would you want the hose to cross the seatstay from the underside to a seat stay mounted caliper? What advantage is there to running under the seatstay? Added protection? Seems like the section crossing te tube would be more likely to get damaged in a crash.
 

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Discussion Starter · #11 ·
Why would you want the hose to cross the seatstay from the underside to a seat stay mounted caliper? What advantage is there to running under the seatstay? Added protection? Seems like the section crossing te tube would be more likely to get damaged in a crash.
Of course one style of routing does not fit all builds but occasionally I see bikes that are built with really strange routing where it looks like the designers don't think about the issue.

I don't think hoses are damaged very often on mountain bikes so I guess it is mostly an issue of style and ergonomics. Once you go with underside you have a flow and if you switch to top side of the seat stay there is a weird transition.

My understanding is that top side routing was related to the way old school canti brakes worked. The side of the top tube routing may be tied to how "V" brake noodles worked. With disk brakes using hose guides, I think using underside is the way to go.

The following are some photos of the style I am using:

Underside of top tube


Underside of seat stay


How about some more photos? What styles do you guys use?
 

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I do it wrong. :)

<a href="https://www.flickr.com/photos/zanconato/8389403855" title="Vince L by Mike Zanconato, on Flickr"><img src="https://farm9.staticflickr.com/8091/8389403855_960b5851b8_c.jpg" width="800" height="600" alt="Vince L"></a>

<a href="https://www.flickr.com/photos/zanconato/8389407529" title="Vince L by Mike Zanconato, on Flickr"><img src="https://farm9.staticflickr.com/8085/8389407529_871a45fb4e_c.jpg" width="800" height="600" alt="Vince L"></a>

<a href="https://www.flickr.com/photos/zanconato/8389409171" title="Vince L by Mike Zanconato, on Flickr"><img src="https://farm9.staticflickr.com/8325/8389409171_efbcc9191f_c.jpg" width="800" height="600" alt="Vince L"></a>

I just try to have the housings cross over as few tubes as possible. That's just me.
 

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+1 for it depends on the frame and possibly how the cables sit in their default position. Cable mounts vary on frames and sometimes "textbook" installs do not work for a non-twisty/tangled configuration. I am not a huge fan of top-side top tube mounted designs (snag the pants most often) and I despise internal cable routing.

I typically wire everything up on MTB's so that the cables cross cleanly and I am able to turn the handlebars 270 degrees in either direction.
 

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Discussion Starter · #16 ·
I just try to have the housings cross over as few tubes as possible. That's just me.
Thanks, for sharing, that's exactly what I am seeking.

I am trying to understand the motivations behind the various styles. Avoiding tube crosses makes sense in the context of paint rub and from a style perspective. I am on the other side of the tube for this issue but the whole point of the thread was to understand what others are thinking about when they route their cables.

Also, great looking work there Zank, it looks like silver on cast hose guides. I have been using the Paragon TIG style with zip ties but think the ones on your bike look cleaner. I also think the Paragon style don't work with the special plastic fittings that you are using and that is part of why I have zip ties on my bike. I worry both about the plastic fittings and the zip ties because I have seen them come come loose on rides.

I am going to stick with underside routing but may consider switching the actual guides around. One thing that I have been thinking about is stainless steel guides and stainless steel wire in place of the zip ties or doing a threaded cable guide like many of the forks use.

Does anyone do something for their guides that they would like to share?
 

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I think the bottom line is that it's pretty hard to make the routing so bad that it causes an actual problem, so do what you like and what works with your componentry/geometry. With my customers I just talk through what I see as the plusses and minuses of the various routing options and let them decide how they want it done.

On my own bikes (personal ones, that is) I pretty much route under the toptube or under the downtube depending on the dropouts. But I've been on pretty much every possible configuration of cable stops/guides in my time and never really had a problem with any of them. On the list of things to optimize about a frame it's pretty far down there.

FWIW, if you want guides for hoses and housing I think the Bikelugs.com ones that Kirk sells are by far the best (light, stainless, cheap, arguably not as bad of a stress riser as a cast/solid guide). Here's a link:
BikeLugs.com

If you don't like zipties safety wire is a good option too.

-Walt
 
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