[5DII]

Bought a steel frame from a custom local well known builder.
The FD cable guide guides the cable against part of the BB shell. Shifting is fine right now, but ideally should it be routed differently? Worried it might eventually wear down the paint or have more friction. The owner said cable sheaths arent necessary.
See photo.

 

[Peter P.]

They're not necessary. Of course the paint will wear but it's no big deal.. Some builders do insert sheaths in the groove if they fit, such as Richard Sachs. Either way is fine but if you want to go that route, just pilfer some from extra shift housing you have on hand.

 

[velodog]

Ain't nothing to worry about. Just ride and enjoy the bike and quit fretting.

Paint wear=beausage, the beauty of use.

 

[MDM]

Do yourself a favor and put on a set of Jagwire Road Elite cables. Running a bare cable over that bottom bracket shell is going to cause a lot of friction and negatively affect your shifting.

 

[tlg]

Looks like a friction nightmare.
You can see on both cables where they enter the guides they make a sharp bend.
The FD cable wraps 90° around the shell.
The guides look like they're designed to perfectly trap grit and gunk. Clean them with a toothbrush frequently.

Do yourself a favor and put on a set of Jagwire Road Elite cables.

+1
Back when I used cables, Road Elite's were all I would use. Totally sealed and maintenance free.

 

[jetdog9]

Some of this stuff (cable liner) might help. Of course you don't need 30 meters worth:
https://www.amazon.com/Jagwire-Black-Housing-Liner-Cables/dp/B0029LF1XO/

PM me your address and I can mail you 6" worth if you want.

 

[Opus51569]

PM me your address and I can mail you 6" worth if you want.

Perv...


Sent from my iPad using Tapatalk

 

[jetdog9]

Oh geez I didn't even realize. I said something similar in a work meeting once and my co-workers wouldn't let go of it for years.

 

[GKSki]

My Pinarello Gavia TSX is routed with even less. 2 loops to go through bare over the BB shell. Never a problem and no friction I can discern. Yeah, eventually they'll wear grooves in the paint, but we're talking under the bottom bracket.

 

[Kerry Irons]

Some of this stuff (cable liner) might help.

Yup. Go to any bike shop and ask them to snip you enough for the job. They will have lots of it on hand.

 

[DaveG]

Bought a steel frame from a custom local well known builder.
The FD cable guide guides the cable against part of the BB shell. Shifting is fine right now, but ideally should it be routed differently? Worried it might eventually wear down the paint or have more friction. The owner said cable sheaths arent necessary.
See photo.

I had this same conundrum when I built up my Mondonico 2 years ago. I bought some of the cable housing, per advice here at RBR, but in the end decided to try it "bare". I don't have an issue with friction and shifting but what I do notice is if I don't ride the bike for a while and conditions are humid, light rust will form between the cable and shell. This can cause the first couple of shifts to be very stiff. So, I try to keep the area clean and hit it with some WD-40 occasionally. Next time I change cables will try the sheathing

 

[flatlander_48]

Ain't nothing to worry about. Just ride and enjoy the bike and quit fretting.

Paint wear=beausage, the beauty of use.

On a steel frame that can lead to Rust...

 

[velodog]

On a steel frame that can lead to Rust...

Yep, and so can a rock chip caused by a tire kicking up some road debris. A bike's not a painting to be hung on a wall an looked at, it's a vehicle to be ridden and enjoyed.

I've got a couple of DeRosa's since the mid 80's, with the cables running under the bottom bracket, one with the original friction shifting and the other has been updated to indexed 10 speed and no problem, they both shift fine and no rust issues. Yes the cable will wear thru the paint, but the cable rub will also polish the exposed metal keeping rust at bay.
I've also got a late 70's or early 80's Miyata that I bought 2nd hand with brazed on above the bottom bracket cable guides, no problem. And this bike sees absolutely no maintenance. My wife has a mid 80's Univega, of which she is the original owner, which also has above the bottom bracket cable guides, and guess what, no problem.

If you want to worry about rust on a steel frame focus on the brake cable guides on the top tube, they collect sweat and aren't as robust as a bottom bracket. They will not only rust, they will rot right off the bike.

 

[MDM]

Those look like those expensive Shimano polymer coated cables. How long do you think that coating will last rubbing on those unlined cable guides around the bottom bracket?

 

[DaveG]

If you want to worry about rust on a steel frame focus on the brake cable guides on the top tube, they collect sweat and aren't as robust as a bottom bracket. They will not only rust, they will rot right off the bike.

I have generally have not had major issues with rust on my steel bikes, but I had a Torelli that always had problems with the rear brake cable stop. Every winter I had to wire brush the stop, treat with rustoleum and re-paint. None of my other bikes were as bad.

 

[flatlander_48]

Yep, and so can a rock chip caused by a tire kicking up some road debris. A bike's not a painting to be hung on a wall an looked at, it's a vehicle to be ridden and enjoyed.

I've got a couple of DeRosa's since the mid 80's, with the cables running under the bottom bracket, one with the original friction shifting and the other has been updated to indexed 10 speed and no problem, they both shift fine and no rust issues. Yes the cable will wear thru the paint, but the cable rub will also polish the exposed metal keeping rust at bay.
I've also got a late 70's or early 80's Miyata that I bought 2nd hand with brazed on above the bottom bracket cable guides, no problem. And this bike sees absolutely no maintenance. My wife has a mid 80's Univega, of which she is the original owner, which also has above the bottom bracket cable guides, and guess what, no problem.

If you want to worry about rust on a steel frame focus on the brake cable guides on the top tube, they collect sweat and aren't as robust as a bottom bracket. They will not only rust, they will rot right off the bike.

I’m a retired mechanical engineer. To me, the important thing is to respect your machinery. One way to do that is to take care of it. I put close to 6,000 miles on the steel BreakAway that I had before it was stolen and it didn’t have one stone chip. Anyway, more importantly, Campagnolo supplies a plastic cable guide that attaches under the bottom bracket. It covers the entire curvature and clearly minimizes any wear on the cable and the degree of drag on it is consistent...

 

[GKSki]

I have the same take as Velodog concerning the cable routing under my Pinarello's BB. Probably 20+ years and never a problem.

I don't think there's right and wrong answer here. If you want to use the sheath, that's fine, and if you want to run the bare cables as the builder imagined, that's fine too.

 

[DaveG]

I’m a retired mechanical engineer. To me, the important thing is to respect your machinery. One way to do that is to take care of it. I put close to 6,000 miles on the steel BreakAway that I had before it was stolen and it didn’t have one stone chip. Anyway, more importantly, Campagnolo supplies a plastic cable guide that attaches under the bottom bracket. It covers the entire curvature and clearly minimizes any wear on the cable and the degree of drag on it is consistent...

Flatlander, steel bikes that have metal guides brazed on to the bottom bracket (like in the OPs photo) won't allow a plastic cable guide. So the question is do you use the guide bare or add some sort of sheathing

 

[velodog]

I’m a retired mechanical engineer. To me, the important thing is to respect your machinery. One way to do that is to take care of it. I put close to 6,000 miles on the steel BreakAway that I had before it was stolen and it didn’t have one stone chip. Anyway, more importantly, Campagnolo supplies a plastic cable guide that attaches under the bottom bracket. It covers the entire curvature and clearly minimizes any wear on the cable and the degree of drag on it is consistent...

Mechanical engineer or not, honest wear is not a sign of disrespect to machinery or a tool, it's a sign of use. There is a difference between wear from use, and damage from abuse.