Front derailleur

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banik69
Posts: 118
Joined: Tue May 03, 2016 6:34 pm

by banik69

Hi there, is this normal guys ?
I mean the flexibility of front derailleur and the frame....

https://vimeo.com/167720593


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euph
Posts: 161
Joined: Wed May 13, 2015 10:35 pm

by euph

That looks entirely normal to me. You're putting a force on the cage where it was never designed to withstand such a force. No surprises that it flexes a bit. Someone with more experience is welcome to chime in but that is my thinking.

fh8425
Posts: 132
Joined: Fri Dec 04, 2015 3:20 pm

by fh8425

looks normal to me too ...

Just a suggestion .. you should not do it anymore as i can see the flexing of the braze on against the seat tube ... you may accidentally damage the mounting of the braze on without knowing .. just my 2 cents.

banik69
Posts: 118
Joined: Tue May 03, 2016 6:34 pm

by banik69

fh8425 wrote:looks normal to me too ...

Just a suggestion .. you should not do it anymore as i can see the flexing of the braze on against the seat tube ... you may accidentally damage the mounting of the braze on without knowing .. just my 2 cents.

This is what I mean, that flex exactly at the tube


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fh8425
Posts: 132
Joined: Fri Dec 04, 2015 3:20 pm

by fh8425

banik69 wrote:
fh8425 wrote:looks normal to me too ...

Just a suggestion .. you should not do it anymore as i can see the flexing of the braze on against the seat tube ... you may accidentally damage the mounting of the braze on without knowing .. just my 2 cents.

This is what I mean, that flex exactly at the tube


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I think what you trying to say is you suspect the seat tube is flexing too much or maybe the braze on bracket is not fasten tight enough to the seat tube. Maybe you get your LBS to take a closer look.

Mep
Posts: 516
Joined: Fri May 28, 2004 4:11 pm

by Mep

My vote is to tighten the cable tension.

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bikerjulio
Posts: 1900
Joined: Fri Dec 11, 2009 10:38 pm
Location: Welland, Ontario

by bikerjulio

I have a bunch of bikes sitting around and I cannot get flex like that. Perhaps that's because they have clamp-on FD's or adapters.

So in answer to the question, perhaps it's normal for a frame with a flimsy braze-on.
There's sometimes a buggy.
How many drivers does a buggy have?

One.

So let's just say I'm drivin' this buggy...
and if you fix your attitude you can ride along with me.

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Calnago
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by Calnago

Yes, my Colnagos have steel Brazeons and they don't flex at all. A lot depends on the layup of the carbon around the brazeon, or in a lot of cases, the bolt-on. Flatter frame tube profiles in that area will likely flex more. I was only trying to concentrate looking at the flex right at the Brazeon and the frame in your video and not the flex from you pulling and pushing it at the tail end of the derailleur. Whatever it is, not really much you can do about it except on the newer front derailleurs there's a support screw or "arm" (S2 Campy 2015 and onward) that lays against the frame for added support.
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2old4this
Posts: 366
Joined: Mon Jan 13, 2014 7:26 am

by 2old4this

I think that flex is too much. What I can't say is if the seat tube is flexing as well or if it is just the braze on. If the entire seat tube flexing, just take it to a carbon specialist and have it checked.

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