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I'm a "she".
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Discussion Starter · #1 ·
After a little over two month of riding, this happened to my rear shifter cable:
<a target="_blank" href="http://www.mudncrud.com/gallery/main.php?g2_view=core.DownloadItem&g2_itemId=48877"><img src="http://www.mudncrud.com/gallery/main.php?g2_view=core.DownloadItem&g2_itemId=48874&g2_serialNumber=3" /></a> (Click on the thumbnail to see the full size.)

Okay, it seems that introducing the bend by routing the cable(s) above that horizontal beam in that link piece is not such a good idea. (It seemed a good idea at the time of assembly because the cable cleared the shock.) The underside of the housing at the bend wore through, but even the upper side of that bend showed some abrasion. In addition, a little piece of paint in the top tube is missing where the shifter cable comes out of the top tube.

This is the brake cable. There is a small groove in the carbon fiber link piece under the cable already.
<a target="_blank" href="http://www.mudncrud.com/gallery/main.php?g2_view=core.DownloadItem&g2_itemId=48901"><img src="http://www.mudncrud.com/gallery/main.php?g2_view=core.DownloadItem&g2_itemId=48898&g2_serialNumber=3" /></a> (Click on the thumbnail to see the full size.)

I noticed that most, if not all, FTMs posted on this forum route the cable as shown on Titus website:
<a target="_blank" href="http://www.mudncrud.com/gallery/main.php?g2_view=core.DownloadItem&g2_itemId=48912"><img src="http://www.mudncrud.com/gallery/main.php?g2_view=core.DownloadItem&g2_itemId=48910&g2_serialNumber=3" /></a> (Click on the thumbnail to see the full size.)

Okay, I'll try that way -- route the shifter and brake cables through that hole between the shock and the beam. But what I don't get is, when the suspension compresses, where will the cables go? Will there be constant chafing between the cables and the enclosing top tube? For you guys, esp carbon FTM owners, who route the cable this way, do you notice any abrasion at any spot?

Any suggestion?
 

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Does the housing not slide easily through the frame openings? I figured it would slide through the frame openings and curl out between the bars and the other opening close to the headtube.

The routing is much better now vs the way it was done in 09 though.
 

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I'm a "she".
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Discussion Starter · #3 ·
terrible said:
Does the housing not slide easily through the frame openings?
Did you mean the housing inside the frame (for internal routing)? I didn't think it should slide and since both the brake cable and the shifter cable go through the same tunnel, it does not seem to me that any slide is expected to happen. No, the answer is the housing do not slide easily.

But back to the routing question. Take below FTM Ti as an example, what would happen to the piece of cable (and housing) when the shock fully compresses? Since the housing would not shorten, it has to bend either upward (hitting the bar) or downward (hitting the shock), right? Has nobody noticed any rubbing?

Oh, BTW, I just read in the Technical Service Instructions for my Shimano rear derailleur: "Use a frame with internal cable routing is strongly discouraged as it has tendencies to impair the SIS shifting function due to its high cable resistance." But I love my internal cable routing!
 

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mudworm said:
Did you mean the housing inside the frame (for internal routing)? I didn't think it should slide and since both the brake cable and the shifter cable go through the same tunnel, it does not seem to me that any slide is expected to happen. No, the answer is the housing do not slide easily.

But back to the routing question. Take below FTM Ti as an example, what would happen to the piece of cable (and housing) when the shock fully compresses? Since the housing would not shorten, it has to bend either upward (hitting the bar) or downward (hitting the shock), right? Has nobody noticed any rubbing?

Oh, BTW, I just read in the Technical Service Instructions for my Shimano rear derailleur: "Use a frame with internal cable routing is strongly discouraged as it has tendencies to impair the SIS shifting function due to its high cable resistance." But I love my internal cable routing!
Yes, cable rub is a problem. Even on my ML (set up like your last picture), the cable rubs the seat and top tube. I have placed frame patches on those areas to prevent damage. I also am getting rubbing of my link, which will eventually saw the damn thing in half!

I would ignore what shimano says with internal routing.
 

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Dozer
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mudworm said:
But back to the routing question. Take below FTM Ti as an example, what would happen to the piece of cable (and housing) when the shock fully compresses? Since the housing would not shorten, it has to bend either upward (hitting the bar) or downward (hitting the shock), right? Has nobody noticed any rubbing?
I have noticed that with my ML, the cable housing and brake hose actually flex out to either side horizontally rather than up or down when the shock is compressed. They also sort of criss-cross each other, so really the only rub I'm getting is a little bit of the hose on the other cable housing. It hasn't been an issue at all yet.
 

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There are already a few threads on bad cable routing. I still think this is a design flaw which Titus had never rectify it. The rubbing of the cables on the seattube and rocker is not so bad for motolite. But when 09 ftm came, the problem got worse as the rear shock is more progressive. And this continues on the 2010 Titus, ESP the carbon where the rub will be more serious. Now, the trick is....the 2 fixed points. As pointed out by a bro earlier, the cable has to bend very badly within the rocker thus rubbing the paint or carbon off. What you can do is the lenghten the 2 fixed points..
 

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Discussion Starter · #7 ·
I replaced the cable last night. After taking the broken shifter cable out, I ran my fingers along the brake cable where it comes out of the top tube (again, internal cable routing), it was very obvious that that 2" section of housing had been worn. I'll need to keep a close eye on its wear and replace it before the mineral oil gushes out of it someday.

It seemed to me after playing with the compression cycles that with internal cable routing, the designer did mean to have the two cables go back and forth in the top tube. I don't see another way unless I put a zip tie around the two cables where they exit the top tube (on the seat tube end). I haven't done it, but am contemplating. Mainly, do I want the wear inside the top tube where I can't inspect, or do I want the wear at the hole (from zip tie hitting it)?

Now, routing the cables as shown on Titus website, I could see that some rubbing on the rocker link (on the inside) is inevitable, ziptie or not. I should tape it. What's the best tape on the market out there for this use?

On the other hand, Shimano is so determined to discourage internal cable routing that the shifter cable kit they make has the housings pre-cut too short. I got a good laugh out of it when I opened the package.
 

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mudworm said:
It seemed to me after playing with the compression cycles that with internal cable routing, the designer did mean to have the two cables go back and forth in the top tube. I don't see another way unless I put a zip tie around the two cables where they exit the top tube (on the seat tube end). I haven't done it, but am contemplating. Mainly, do I want the wear inside the top tube where I can't inspect, or do I want the wear at the hole (from zip tie hitting it)?

Now, routing the cables as shown on Titus website, I could see that some rubbing on the rocker link (on the inside) is inevitable, ziptie or not. I should tape it. What's the best tape on the market out there for this use?
Has your local dealer had a look at the cable routing? Did they not build it up for you?
Check out Frameskin.com
Here's an IbisTranny kit he offers. Very clean and strong.
 

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Try to get your hands on some of the stuff they put on Cars, Clear Bra. you can go to a place that installs it and ask for a piece, then you can cut it to what ever shape you want. its a lot less expensive then the pre-cut mini band-aid crap you get at a bike shop. you can get it thicker as well so it will last a lot longer. If you do a web search I think 3M make it and you can get small 12" x 18" sheets. I did and I have more than enough. I think I got it from a company called Clear Defender, under Bulk film. You can buy it by the foot in different widths. hope this helps.
 

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Discussion Starter · #11 ·
Bikerbob.com said:
Has your local dealer had a look at the cable routing? Did they not build it up for you?
The dealer who built my bike is not so local for me. Plus, FTM carbon is new in 2010, so it's not like any local dealer has assembled tons of them. On top of that, I feel that this is something one just has to figure out by trial and error... and maybe with some help from MTBR. I have fun and learn a great deal in the process.

I'm lazy, so if frameskin.com made a kit for FTM carbon, I would go for it, but it does not seem like that's the case. Are those a bunch of Scotch tapes in that Mojo photo? Doesn't look strong and clean to me. (Just kidding...)

malen, thanks for the information. I need to digest it a bit since it's a lot of brand names, Clear Bra, 3M, and Clear Defender.
 

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Discussion Starter · #12 · (Edited)
malen said:
...If you do a web search I think 3M make it and you can get small 12" x 18" sheets. ...
Just to confirm, malen, is this what you are talking about? Did you buy it online or do you know if any local shop (chain or not) may carry them?

Edit: By using "Where to Buy" on 3M website, I found a dealer very close to me. Will check them out soon.
 

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To continues with my previous post, my shifter cable rub against the seattube until the metal wires of the internal housing and be seen. So imagine having the metal internal shifter housing rubbing against my anodized frame and plus lots of ghost shifting due the cramped up cables between the two fixed point. The solution is.......the rear shifter cable.... Unfix the 2nd fixed point by use a cable tie ring for the rear d cable. Now you have a longer lenght for the cable movement and this reduces the cable pull due to the rocker movement. See the run of the rear brake cable as an example. Now no more ghost shifting and nasty rubs .
 

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Discussion Starter · #14 ·
mambo76 said:
Unfix the 2nd fixed point by use a cable tie ring for the rear d cable.
Thanks for sharing. By 2nd fixed point, I assume you meant the one on the seat post. Got a picture of your setup?
 

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The 2nd point is at the seat stay. There is another point just before the rear Dee but you have to keep that fixed to avoid ghost shifting. With the 2nd point unfixed, you will have a longer lenght of cable to spread the bending of cable out. Other the bending of cable only limit to the lenght within the carbon rocker. Let go the air in the rear sus, press yr seat down and you will see how bad the bends of the shifter cable. A portion rubs the rocker and another rubs the seattube. I had my anodIzed paint rubber off with 2 months.
 

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The shifter cable and brake hose are designed to run under the rocker bridge. This allows them to travel through the internal routing as the bike goes through the suspension. The edges are also smoothed to prevent the housing from being damaged. The pictures on our website show the best way to build the bike.
 

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Discussion Starter · #18 ·
Titus_Mikey said:
The shifter cable and brake hose are designed to run under the rocker bridge. This allows them to travel through the internal routing as the bike goes through the suspension. The edges are also smoothed to prevent the housing from being damaged. The pictures on our website show the best way to build the bike.
Thanks Mikey for confirming that. I'm less concerned about the housing than the hose being worn through. After 2+ month of riding, the wear is there, although I'm not sure if any picture can show it. Now, I have wrapped the hose with electric tape where it exits the top tube. Will see how it holds up. A friend suggested Housing/hose frame protector. I may look into that.
 

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Discussion Starter · #19 ·
Was at Spokesman (in Santa Cruz) for some else, and started talking about the cable routing. It spiked Wade's interest. When he geeks out on stuff, usually something good comes out of it. (My custom made GPS holder is an example.) I showed him a pix of sworksflux's rig. He machined this for me (out of a spoke wrench):


The cables can still run length-wise freely as intended.
 

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