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ontarget
07-11-2017, 08:21 AM
My front derailleur cable is beginning to fray, so I need to replace it. I've never done this on this particular bike before, and have a question for you all before I screw something up.

The cables are externally routed. The FD cable runs on the bottom side of the downtube, through a guide on the bottom side of the BB, through a hole in the bottom side of the BB area, then out a hole in the top side and to the derailleur. The portion going through the BB area looks like a straight shot. Should I expect to be able to just insert the new cable without much fuss, or do I need to attach a string to the old cable to use for pulling the new cable through? Or some other technique?

Thanks!

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AngryScientist
07-11-2017, 08:22 AM
what bicycle are we talking about here?

a picture of the BB area would totally help...

Blown Reek
07-11-2017, 08:33 AM
If it's external and your bottom bracket guide looks like this,

https://www.universalcycles.com/images//products/large/6695.jpg

then all you have to do is route the cable. No other tools or tricks necessary. Easiest thing to do in the world.

eddief
07-11-2017, 08:56 AM
I had a Spec Roubaix where the channel through the bb was a bit clogged up. I think there was a plastic tube through which the cable had to pass. It took a bit of "jamming" of the cable to clear the path. But I'd guess if when you take out the old one and if it comes out smoothly, then inserting the new one should go smoothly too.

seanile
07-11-2017, 08:57 AM
could look like this, in which case you want the little plastic tubies
https://www.pedalroom.com/f/8c0e7df19d_4.jpg

ColonelJLloyd
07-11-2017, 09:04 AM
If it's like the Merckx you can rob the lining from sold old housing by dissecting carefully with a razor blade.

zmudshark
07-11-2017, 09:06 AM
If it's a straight shot, it's a straight shot. Should be easy-peasy.

ontarget
07-11-2017, 09:35 AM
Sorry for the lack of photos previously. Here are a couple quick ones I took as I was heading off to work this morning.https://uploads.tapatalk-cdn.com/20170711/12499de1b17f55beeaa259a32835904a.jpghttps://uploads.tapatalk-cdn.com/20170711/2fd0c5bce6f68970572217b824a88569.jpg

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icepick_trotsky
07-11-2017, 10:09 AM
I think you just poke that through as is and cross your fingers.

David Kirk
07-11-2017, 10:17 AM
Start with a brand new uncut cable so that it's soldered closed on the end and this will allow you to poke and jab it through without worry of it fraying. Then once you get it all set up cut it to length.

dave

Blown Reek
07-11-2017, 10:56 AM
I think you just poke that through as is and cross your fingers.

Start with a brand new uncut cable so that it's soldered closed on the end and this will allow you to poke and jab it through without worry of it fraying. Then once you get it all set up cut it to length.


Yes and yes. Poke gently.

ontarget
07-11-2017, 03:38 PM
Thanks for the feedback, everyone. Much appreciated!

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dustyrider
07-11-2017, 03:42 PM
:beer:

Mark McM
07-11-2017, 03:50 PM
That's an awfully sharp bend where the cable enters the BB shell - not a particularly well executed design. While I'm sure it can work at some level, the derailleur cable can easily get a kink at the bend, hampering the shifting performance a bit. Not to mention that if you shift the front derailleur a lot, the cable may slowly saw its way through the BB shell.

What brand/model bicycle is this?

Hilltopperny
07-11-2017, 03:56 PM
I took a pipe cleaner and threaded the cable through it and through the frame on my internally routed bike. Before I figured that out it seemed impossible.

ontarget
07-11-2017, 06:10 PM
That's an awfully sharp bend where the cable enters the BB shell - not a particularly well executed design. While I'm sure it can work at some level, the derailleur cable can easily get a kink at the bend, hampering the shifting performance a bit. Not to mention that if you shift the front derailleur a lot, the cable may slowly saw its way through the BB shell.

What brand/model bicycle is this?
It is sharp, indeed. The bike is a 2012 Fuji Altamira LTD. Any suggestions as to what can be done about it?

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eddief
07-11-2017, 06:14 PM
a piece of plastic tubing in that channel. it could be old and used up. not sure if there is if it is replaceable or not. check it out, let us know.

It is sharp, indeed. The bike is a 2012 Fuji Altamira LTD. Any suggestions as to what can be done about it?

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ontarget
07-22-2017, 10:13 PM
Just want to provide some follow up on this. I replaced the cable. It went in without a hitch. It felt like there was some sort of channel. In other words, I didn't have to fish it through the entrance and exit holes ... it went there on its own, and felt as if there was a hole through an otherwise solid piece of material.

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