Cyclelogikal

Call me old fashioned but I like external. I like to see the componetry and if I have a issue and not have it hidden.

BigJeff

Hence CX bikes have the cables on the "top" of the top tube, so when you shoulder your bike you don't snag the cables.

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What is more aerodynamic drag, external cables or wrinkles in your jersey?

TrojanHorse

Structural liner? Where is this mythical construct?

I like internal cables. It just looks better, I can't conceive of any actual benefit... maybe the cables stay cleaner but I've never really had a problem with that anyway. You can't clamp carbon frames so there's no advantage there either.

It does make it a tiny bit easier to clean the bike. I have SRAM shifters, which require more force than shimano apparently, so I didn't notice any degradation in shift quality when I went from an external frame to an internal (same groupset on both bikes) but I have heard of people with my exact frame who have issues with shimano drive trains, so who knows.

As long as you have all the little sleeves to run your cables it's not really appreciably harder to route than external cables but if you lose them or forget to put them on before replacing cables then external would be a lot more pleasant to deal with.

carpediemracing 

Fixed

carpediemracing 

Internal cables implies having stops for housing and some kind of way of getting around the BB. I imagine on factory bikes it's tougher to make a frame with that stuff. Most frames, with essentially round tubes, don't lend themselves to an internal set of derailleur cables - drawing a straight line (because derailleur cables are best when working in a straighter line) you end up outside the tube, especially when you consider the standard BB cable guide as the end point at the bottom of the frame.

Significantly a derailleur cable's tension affects shifting. If the cable tension changes somewhat minutely it can make the shifting go haywire. This is not the case with brakes.

With a brake both those things are not as complicated. First you only have one cable, and it only goes along the top tube. Lots of internal brake cables consists of some hole that allows you to run the full cable+housing through the frame. No worries about stops, etc, just put two holes in the top tube. Easy to manufacture, no worries about variable cable tension once it's set up.

Having said that I prefer internal cables. I have two inexpensive custom frames ($750 a frame, today $950 or something like that). On the second one I specifically specified internal derailleur cables (and rear brake cable) because it's much easier to clean the top and down tubes when the cables are inside, downtube especially. I had the builder use an aero downtube and it jutted down a bit past the BB with no closure so the cables could come out of the end of the cable. From there they ran along a normal BB cable guide. The very rear is external, i.e. a little loop of housing to the derailleur. The front derailleur cable, due to the wide seat tube (also aero) has a hole for the cable to exit. Since it was a high friction set up I simply used the liner of the housing all the way to the derailleur.

BB area, showing opening at bottom of down tube:


Hole for front derailleur cable:


The first is the key to the frame. Without the slight overhang of the tube and the open end of the downtube it would be hard to have a clean, smooth way for the derailleur cables to exit the frame. I tried thinking of lots of ways to do it but the open down tube (suggested as well by the builder) was the best solution.

The top of the derailleur cable bit is simply a cable stop that covers a hole for the cable to enter the downtube:


Disadvantages of that frame? Well, it's a touch heavier, more time consuming to build, and it has more things to go wrong with it (in assembly as well as in use). Compared to my very normal other frame it's 240 grams heavier (1680g vs 1440g). This is heavy compared to the current crop of lighter frames (my frame before these bikes was a SystemSix, 1150g).

As far as shifting goes it's been fine except when the left side boss had a problem. I lost the ability to tension the left cable so the derailleur dropped down to the 39T chainring. Other than that for the two years I raced/rode it it's been fine.

So it's possible to do it, it just takes a little bit more time, money, and possibly some weight.

TommyBing

Maybe at Tuesday Night Worlds that has a semblance of relevance, but at the Continental Pro level and above, there's very limited service being rendered apart from a new bike getting quick-released off of a roof rack.

And so the question remains. Why not internal? Since 80%+ of the people reading this will be taking it to an LBS for new housing/gear, and it looks cooler, so I can't see how any decent bike will have external cables in 5 years. My cyclocross bike is my road bike, and the practicality of internal routing is evident. Minimal or at least marginal gains on a road bike, I recognize this, but obviously looks sleeker.

Campagnolo had an internal memo during Ultra Torque and Power Torque development that mentioned the lack of the tool availability which would bring foot traffic into Italian and Croatian shops. Unlike in the U.S., in Italy and Croatia, even the newbs and Freds do all their own work.

jmX

I'm not going to say all bikes should have internal, but certainly I'll be specifically looking for internal cabling on every future road bike I buy. I can see how mechanics might dislike it since it takes a little longer to run the cables and they do it constantly, but for all of us, seriously? How many times do you change your cables?

I've redone cables on 4 of my bikes over the last 3 years (not always because I had to, some were simply upgrades), 2 external, 2 internal, and the difference in hassle is pretty small. It looks slick, it works perfectly, and costs me 20 minutes of extra time a year. I even just re-did my main bike with Di2 and running the electric wires inside the frame was a piece of cake. I'm just a random joe blow, not some mechanic. Not a rocket scientist. Heck if you BUY a bike already setup, then running new cables is dead simple...they'll even give you free sheaths to slip over the old cable before you remove it which will maintain the pathway for the new cable to go in. Once you're done, pull the sheath out, and you're good to go. If that extra 20 minutes once a year is a big deal to you, fair enough, stay external.

I get that it's not for everybody, but it's available, it works, and every time I carry my bike or wipe down the tubes without cables getting in the way I'm glad I've got it.

danvuquoc

Shoulda gone with di2, mine is all internal

RT

The first answer is the correct one. Well done, sir.

Daytrip

It's not as hard as you might think. I've done it more than once (Doh!).

the sci guy 

i don't really mind either way aesthetically, but my big worry is the cables that are on the top of the top tube are going to get damaged when i pull the straps down over them too tightly on my trunk mount bike rack (it's a yakima and has the stretchy rubber straps with the holes). does that hurt them?

MegaTom

The cables might scratch your paint. Put a rag or piece of something in between cable and frame so they don't rub.

the sci guy 

it's an old 90's MTB i got off craigslist that has plenty of chips and scratches and small rust spots. don't care about the paint, just the functionality of the cables

RT

Relevant story: I just now changed my 9 speed's der cables and housing in less than 10 minutes. Wasn't in a rush or pressed for time at all, it was just plain easy. Brake cables and I have no choice but to re-wrap my bars, which I hate doing.

Alloyrider

I picked my Madone2.1 over the Domane 2.1 because it had internal cables. I think it looks alot cleaner and less hassle to caryaround with less chances of the cables getting snagged on something in my apartment. This is also my first road bike so maybe my opinion will change with time.

Hiro11

That's a pretty big assumption.

Reasons not to go internal:

1. It's much easier to swap out an external cable and housing. Much easier. With external, everything is exposed and there's nothing to go wrong. In contrast, if something gets stuck in an internal cable, you could have a real pain on your hands to fix it. Ask me how I know this.

2. In almost every case, external offers lower friction. Better shifting and braking result. Significantly better in many cases.

3. Many internal cables rattle and fixing this issue can be a pain. This is true even with many extremely high end bikes

4. Internal cabling makes it that much easier for water to get in the frame.

5. Many internal cabled frames have integral housings. You basically can't swap these out and are stuck with slowly degrading performance that you cant really fix.

As someone who does all of the servicing on his own bikes, I'll stick with external. And BSA, thanks.

LamontC

My single favorite thing about my road bike is that it is completely silent. No chain/gear noise, no frame sounds, no bottom bracket creaks, nothing but luxurious wind sounds. I mean, it's fast as hell, but it's the "sound" of quality that makes it feel like a top-end bike to me. It happens to be externally routed. Has anyone had actual experience with rattling of internal cables? That would be my biggest fear with going that way.

cerealkilla

Yes! the SCOTT FOIL 15 I had. The rear break cable slapped around inside the top-tube when going over bumpy/old tarmac. Something I really disliked. I also enjoy the slickness of a silent bike, just tyres, wind and the sound of my lungs going pleases me knowing its all running 100%

RJM

External for me...I even like the way it looks.