Had the most bizarre wrenching experience yesterday

[weisan]

A friend was having shifting issues so I took her bike home to look at after our ride yesterday.

It was an older model Giant TCR. Up until yesterday, I have never worked on bikes that use internal routing, except the nominal top tube internal on my LOOK which was easy and straightforward, doesn't pose any difficulty at all.

Long story short, I ended up having to replace her rear deraileur cable and encountered some difficulty trying to get it routed. Finally, got it done using the "trick" of tying dental floss to one end of the cable with the idea of sucking the floss out the other end using a vacuum cleaner and then pulling the cable out with it. Well, this is the bizarre part. For a while, I couldn't push the cable through on its own but as soon as I tie the dental floss to it, miraculously, it just came out on the other end without much plodding. I didn't even get to use my vacuum cleaner. So I guess, the key to a easier life with internal routing is tying dental floss to cable. I get the message now. :D

I can understand and appreciate the sleek and cleaner look of internal routing and it has probably improved in its design, ease of assembly and application since my friend bought her Giant several years ago.

[Gummee]

Yeah, sometimes you get lucky.

AFA that last sentence: uhhhh no. They haven't improved anything with internal routing since that Giant. If anything, it's gotten worse

M

[peanutgallery]

Plastic cable sheathing and the park internal kit in a pinch

Internal is way cleaner looking, you just have to think ahead when working on it. For the record, internal cabling on $500 Boomer Bikes are completely unnecessary

[eddief]

https://www.parktool.com/product/internal-cable-routing-kit-ir-1-2

[AngryScientist]

i've been working on cars, boats, motorcycles, jet skis and bikes for a long time.

over the years, i've resorted to all sorts of crazy tricks and hacks to get the job done, and re-purposed a whole bunch of household items to "no-traditional" use, haha.

[Veloo]

Haven't actually worked on many internally route bikes myself.
A 90's steel frame with SL tubing I owned had internal top tube routing but even that had internal guides so it was a no-brainer to fish a cable through.

I just assumed today's $3K+ carbon frames integrated some kind of routing (despite the additional weight) to make life easy(er) considering the money spent on them.

[jbay]

So I guess, the key to a easier life with internal routing is tying dental floss to cable. I get the message now. :DWhat type of dental floss do you recommend?

[choke]

https://youtu.be/smZA9Jv3qH0

[dem]

So I've only replaced 1 internal cable, and once a cable is in there, replacing seemed trivial - cut off end of cable, slide cable liner tubing over the whole internal cable til it pokes out the other end, remove old inner, insert new inner, pull out tubing?

Is there some reason this is more challenging on other bikes?

[Andy sti]

So I've only replaced 1 internal cable, and once a cable is in there, replacing seemed trivial - cut off end of cable, slide cable liner tubing over the whole internal cable til it pokes out the other end, remove old inner, insert new inner, pull out tubing?

Is there some reason this is more challenging on other bikes?


It’s more challenging if you don’t do that first. :banana:
Yes, you described the proper way.

[steelbikerider]

I have built up about a half dozen used ex pro team bikes and a couple of used tt frames. For whatever reason NONE of the pro team bikes had a single cable or liner or even cable fittings left and all had been used, some extensively. The only saving grace was that the bottom bracket wasn't installed or was bearings only and no sleeve. Some took 2 hours, others 30 minutes and the cables came out right where they were supposed to the first time. TT and aero bikes with all cables going in behind the stem on the top tube are the worst.

Needle nosed pliers with an angled tip are a great help.

[redir]

Magnets work well too.

[cmg]

You could also cut off the ball/barrel lead piece at the shifter and tape the new cable to it and pull it through to the derailleur.

[benb]

I have been procrastinating changing the cables on my Trek Domane for a long time over this.

I have all the new supplies sitting in the garage and have still not started it a month later. (It probably should have been done years ago)

At least the Trek has a removable panel under the BB so hopefully it won't be too bad.

This stuff just happens with complicated wrenching though. My Honda motorcycle I used to have had 25 different things on it that were about 10x as ridiculous as anything to do with internal cables on a bike though. 36" long screwdriver to get to throttle body retainer screws? CHECK. Drain clutch hydraulic fluid and remove clutch slave cylinder to change the chain & sprockets? CHECK.

[Spaghetti Legs]

So I've only replaced 1 internal cable, and once a cable is in there, replacing seemed trivial - cut off end of cable, slide cable liner tubing over the whole internal cable til it pokes out the other end, remove old inner, insert new inner, pull out tubing?

Is there some reason this is more challenging on other bikes?

There was a guy named Seldinger many years ago who, if he didn't invent it, managed to get his name applied to the technique of placing medical tubes and catheters into difficult spots over a wire. it's used for all kinds of stuff now but I'm not sure if he or his family get a cut. Anyway, same concept as this.

As an addendum, it's a nice touch, if you sell a frame with internal routing, to leave the outer cable, or some other guide wire, in place for the new owner.

[GregL]

This stuff just happens with complicated wrenching though. My Honda motorcycle I used to have had 25 different things on it that were about 10x as ridiculous as anything to do with internal cables on a bike though. 36" long screwdriver to get to throttle body retainer screws? CHECK. Drain clutch hydraulic fluid and remove clutch slave cylinder to change the chain & sprockets? CHECK.Sounds like my wife’s first generation Miata. Everything is packed so tightly together that seemingly simple maintenance tasks require removal of multiple components. Changing the coolant hoses to the oil-to-water heat exchanger required me to purchase a set of long-handled, needle-nose pliers. Work on the lower parts of the engine often requires going in through the front wheel wells. Nearly any repair under the dash requires removal of the entire dash. Love the car, hate the maintenance!

Greg

[benb]

Yah sportbikes are basically that Miata on crack.

The Miata is basically the only car that seems to have the same performance mentality where the vehicle is supposed to get lighter, have it's balance improved, and have it's mass more centralized in each redesign. If that makes something a little tricker to maintain that's OK.

I would have said cars over $100k or $250k or $1M were more like sportbikes but it seems the last 10 years not so much.

If I wasn't over 6' I'd be pretty interested in a Miata... might be workable anyway though. I've never taken one for a drive.

The amount of stuff in a modern style motorcycle and how carefully it's engineered and how much it improves over time always makes me hyper skeptical of the "marginal gains" in bicycles that cost as much as motorcycles.

[dddd]

Using noodle tubing to get the new cable through can sometimes depend on whether the tubing OD can pass through the cable hole at the cable stops, usually (maybe with twisting) it can.
It's the initial build that can be tricky, I even made a long-handled "fork" tool that follows the pair of gear cables from the bb up to the cable inlet ports up near the head tube, verifying that they aren't twisted.

I have to say that I recently built up the most mechanic-friendly frame to date using internal cabling.
It was a Chapter2 Team Issue frame and all of the internal cabling featured in-place permanent end-to-end noodling. So it was as easy as feeding the gear cables in and having them magically emerge from the end of the chainstay and behind the bb shell. Bravo!

This frame further impressed with it's exceptional level of press-fit tolerances at the bb shell, as each cup simultaneously pressed in at the same rate until both seated at the same time (good bb/hdst tool allowing both cups to be pressed in at the same time).

[Hawker]

What type of dental floss do you recommend?

This is going to open up a whole new thread about Dentist bikes isn't it?

[fxyris]

I can understand and appreciate the sleek and cleaner look of internal routing and it has probably improved in its design, ease of assembly and application since my friend bought her Giant several years ago.

Not so, in fact give me the Cervelo S1/Soloist internal cable routing any day. Although long in the tooth now, the shift cables come out super easily through the nice gaping hole at the BB.

[ColonelJLloyd]

What type of dental floss do you recommend?

I have to admit I was genuinely curious.

And do you pull the cable in the direction of derailleur to shifter so you can tie the floss to the shifter end?

[weisan]

What type of dental floss do you recommend?

This is going to open up a whole new thread about Dentist bikes isn't it?

Whatever Costco is selling at a discount right this moment. :D

[johnniecakes]

What type of dental floss do you recommend?

Waxed cinnamon is my favorite

[aaronka]

Magnets work well too.

Second for magnets - have had success with magnets when the floss and vacuum failed me

[weisan]

Second for magnets - have had success with magnets when the floss and vacuum failed me

I tried that.

Got to be some strong magnets though.

[buddybikes]

I've had my internal routing rust (on a Kestrel) which was a horrid mess.