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Discussion Starter · #1 ·
My road bike has an internally routed rear brake cable, which got me to thinking, anyone make a cross bike with internally routed cables? Any disadvantage to it that you can see? Besides cost?
 

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I added internal rear brake routing to an clunker MTB as an experiment. It goes through the TT, exits and then through the seatstay to the caliper. It uses full length housing, so running the cable through is a snap. The downside would be the extra weight.

I may do the same with an old CX frame at some point, just for kicks. Not having any cable on the exterior of the TT or DT would be nice.
 

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Discussion Starter · #4 ·
PeanutButterBreath said:
Not having any cable on the exterior of the TT or DT would be nice.
That was my thought. Granted I haven't even raced my first race yet. I'm probably overthinking this, but figured what the heck and see if it was do-able and/or practical.
 

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TheHeadlessThompsonGunner
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PeanutButterBreath said:
I may do the same with an old CX frame at some point, just for kicks. Not having any cable on the exterior of the TT or DT would be nice.
I had thought about that for the next CX frame I built - brake cable through the top tube, as usual (usual road bike), and both derailleurs through the downtube (which would eliminate a front-derailleur barrel adjuster, unfortunately). The thing that makes me nervous, though, is cutting fairly large holes basically right through the butts. Those brass tubes are generally 7 mm OD, I think, and when you factor in the long oval they require for smooth routing, it seems like two of them opposite each other on the downtube would generate a pretty large stress riser. The other option, three tubes through the toptube, which is at least subjected to different stresses, doesn't seem much better... Dunno, but I'd like to find a nice way to eliminate the usual gaggle of cables on a good CX bike's toptube - besides another singlespeed!
 

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It did take fairly long ovals to run the bass tubes with clean bends. Of course, if you were starting with a single tube instead of a complete frame you could probably do things much more efficiently with tubing selected to mitigate the problems. But I am not a frame-builder or engineer by any stretch.
 

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I wouldn't want internal cable routing on a cross bike. My preference for shift cables is dt routing, like a standard road bike. The rear brake can go along the tt, hopefully on the top of that tube. The extra point of entry for water that would be caused by internal routing doesn't matter to me, I always drill a hole or two in the BB shell so the bike can drain.

I want to be able to quickly replace cables on saturday night after a muddy race. I do not want to be frigging around with magnets, etc trying to snake those cables through the inside of my frame. Keep it simple...
 

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The approach I used does not allow any additional water into the frame. There is a brass tube running the entire length, through which full length housing is run. Makes cable changes pretty simple (and less frequent since full length housing elminates two entry points for water and grit into the cable housing).
 

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Shoulder, "lunchboxing" and running with the bike would be easier I suppose.
 

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i love the internal brake routing on my cross bike. no races on this thing yet. but, i have shouldered it plenty.

since it is a ss, it make the bike clean and simple. if it were full of gears and such, i'd probably would have had to think about internal routing abit more.

<img src=https://farm4.static.flickr.com/3052/2919401373_4ff6d3780d_b.jpg>
 

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My old Klein MTB had internal routing and never had a problem.
Well once while changing the cables and pulled the liner out.
Klein used a small plastic tube that was flaired at the front to keep it from being pulled into the top tube. The tube just stuck out the back. Pretty slick.
I think it could have its place on a cross bike.
 

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TheHeadlessThompsonGunner
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PeanutButterBreath said:
Also, when you sit on your TT drinking a beer after the race you won't be rubbing the cables into the paint.
Believe it or not, that's my favorite thing about it. This applies more to on-road use, but it's so much nicer to sit on at stoplights, too...
 

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Pretender, as you know, riding a cross-check I can't be called a weight weenie, but even I try to make that bike as light as possible. With housing at about 40 grams per meter, I'd guess you can add 60-80 grams of weight with full length cable housing (not including additional brass tubing). Also thought original advantage of cable stops was less friction for better shifting/braking. Maybe the housing has gotten better these days and that is less of an issue.

I had a great ride in the snow last Saturday morning, hope you were able to enjoy as well.
 

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I dig internal routing and if it's done right, it's not a pain in the ass and water entry is a non-issue.

http://www.flickr.com/photos/vertigocycles/2870183381/in/set-72157604733278133/


Also, I hear from several reliable sources that brass isn't necessarily the way to go when brazing in a line for full length housing. Supposedly the repeated flex created by hard braking causes the brass to work harden and over time, develop cracks. Stainless is apparently the way to go.
 

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Discussion Starter · #20 ·
gandhi said:
Fixie Inc's cyclocross "Pure Blood" has internal cable routing. http://www.cycles-for-heroes.com/bikes/cyclocross/pure-blood. Very slick indeed.

I wonder though, if mud can find its way into those holes? It also seems tricky to replace the outer cable.

~K
Looks nice, but the mech cables are downtube run and exposed. Seems counterproductive to me. Granted I haven't raced cross, but it makes sense to me to top tube route everything to keep it out of the mud, like on mtn bikes.
 
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