haphaeu

I've just installed a 105 front derailleur in my cyclocross. The derailleur came without a clamp, so I bought this one one separately.


The clamp fits perfectly the derailleur and frame.


However, this is a down pull derailleur with a pulley, and the cable going down along the vertical frame tube is clashing with the clamp. The clamp is just a little on the way, so it works, but it deviates the wire a little bit and I'm afraid with time it will cause problems - both the cable and the clamp will wear out.


Comparing this clamp with the derailleur I had previously, the brace has a much higher profile, therefore the clash.


As a quick fix, I was thinking about adding a small piece of cable housing, or a deflector, fixed to the clamp, so that the cable doesn't rub against the clamp directly.


But I'm not sure how to fix the problem properly. Is this clamp wrong (too high profile)? I can't see of any other way to install it to have enough clearance.



Top view, clamp on the way above the pulley.


Smallest angle I could fit was passing the wire inside the clamp.

frankenmike 

sch

Ditto frankenmike, the mud and snow from cyclocross will make that invisible in the first hundred meters of riding. It will be years before the
clamp will be compromised and if the cable is stainless it will wear out in the brifter first. If you liked the FD in the long lever arm configuration
(5800 IIRC) you will not be impressed with the 7000 series re-imagining.
From another POV, consider how well the plastic cable guide on the bottom of the BB shell through which the FD cable runs holds up.

haphaeu

Thanks for the replies with your opinions.

Pictures added above. Shifter is properly tuned and working fine, so I don't think it is any installation problem. I guess only way would be to find a clamp with narrow profile. However:

Shifting gears goes without problems, can't tell any extra friction for now. I also suspect that it won't be any major issues, and am tempted to go for it =) I guess worst case in a few years (months?), I'll just replace clamp and wire, which are both not expensive parts.

That's good example, and these wires that go underneath a BB cover a large angle there, so it adds lot's of tension and friction due to Capstan. And surprisingly some of these cable guides are made out of metallic material.


That said, as it stands now, to add a cable housing I would have to disassemble and re-terminate the cable, so not worth it. So maybe I'll try to fit a plastic cable guide to reduce friction, if I find something that fits well, it's quick and simple. Otherwise I'll just leave it and see how it goes.

fietsbob

Tried running the cable down the other way? ..pulling around the pulley, right to left ... then to the FD..

avoids the FD Clamp bolt entirely ..



You could shop for a top pull front derailleur , and not need the redirect pulley.










....

Troul 

It might be feasible to use a spacer in between the frame boss & pulley to offset the pulley out in order to shift out the cable positioning clearing the clamp from the outer side.

le mans

Can't the cable run outside the clamp, or am i missing something?

AnkleWork

You can avoid the pulley and clamp altogether by adding a length of housing between the last stop on the frame and the cable anchor. It should be long enough to allow full travel of the derailleur plus some slack. Your cable will stay much cleaner.

Wilfred Laurier

this^

dsbrantjr

Yes, Never Fix A Running Piece. Keep in mind that the shift wire rubs against metal (the inside of the housing) in normal use without issue. I suspect that the wire will fray or otherwise wear out someplace else first.

trailangel

Same here

fietsbob

40 years ago cables went bare into unlined housing , then they figured out a plastic tubing inside the housing reduced friction a Bit..

CliffordK

There are top pull derailleurs.

Look at the CX70 derailleur.

le mans

Looking at the top view, looks like it would clear the clamp if placed outside, running parallel to the seat tube, if it rubbed a bit on the clamp it could be filed with a small round file so it clears, another approach

Troul 

Install this after rerouting the cable a different direction, if feasible.

https://www.thebikeshopstore.com/cat...IaAqfDEALw_wcB

haphaeu

Interesting. No I haven't tried that. The cable could then rub against itself. Anyway, will give it a try next time I have to un-clamp it.

I'm not sure I understand what you mean.

Yes it can. I've tested that. But the deviation is even larger. I got the cable closer to a straight line after passing it inside the clamp.

That's where I'm putting my money =)