barbags and carbon handlebars

General cycling advice ( NOT technical ! )
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honesty
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barbags and carbon handlebars

Postby honesty » 23 Oct 2013, 10:51am

Is this ok to do, or a big no-no. I'm talking about the rixen Kaul type mount with the restraining cable. I would be concerned with the cable damaging the carbon myself.

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cycleruk
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Re: barbags and carbon handlebars

Postby cycleruk » 23 Oct 2013, 12:48pm

I wouldn't expect carbon bars to be any different to alloy ones.
In fact they may be better?
Carbon products usually have a "varnish" coat which would scratch and show any rubbing or scuffing.
Just be careful that there are no sharp edges, as you would with alloy, and you can possibly fit tape to deter any scratching.
You'll never know if you don't try it.

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foxyrider
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Re: barbags and carbon handlebars

Postby foxyrider » 23 Oct 2013, 6:49pm

My advice would be don't do it. The issue is the 'crushing' action of the bracket regardless of whether its cable restrained against the stem or not - it could potentially cause a catastrophic failure. I'd play safe and put an alloy bar on - its not like the weight is gonna be an issue!
Convention? what's that then?
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cycleruk
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Re: barbags and carbon handlebars

Postby cycleruk » 23 Oct 2013, 7:56pm

foxyrider wrote:My advice would be don't do it. The issue is the 'crushing' action of the bracket regardless of whether its cable restrained against the stem or not - it could potentially cause a catastrophic failure. I'd play safe and put an alloy bar on - its not like the weight is gonna be an issue!


Why would the crushing action be any different than that of the bar clamp fixings?
You'll never know if you don't try it.

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foxyrider
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Re: barbags and carbon handlebars

Postby foxyrider » 23 Oct 2013, 9:01pm

Because the bar is designed for that, its not designed to have something wrapped around it with a bunch of weight constantly jumping up and down against it.

I stick by my advice.
Convention? what's that then?
Airnimal Chameleon touring, Orbit Pro hack, Orbit Photon audax, Focus Mares AX tour, Peugeot Carbon sportive, Owen Blower vintage race - all running Tulio's finest!

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cycleruk
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Re: barbags and carbon handlebars

Postby cycleruk » 23 Oct 2013, 9:40pm

foxyrider wrote:Because the bar is designed for that, its not designed to have something wrapped around it with a bunch of weight constantly jumping up and down against it.

I stick by my advice.


Is an alloy bar designed to take other weights?
I have seen a few alloy bars fracture in our club but never a carbon bar, except in crashes on the track.
If there is any real concerns then we would stick to steel.
You'll never know if you don't try it.

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CREPELLO
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Re: barbags and carbon handlebars

Postby CREPELLO » 23 Oct 2013, 10:31pm

foxyrider wrote:Because the bar is designed for that [ bar clamp fixings], its not designed to have something wrapped around it with a bunch of weight constantly jumping up and down against it.

I stick by my advice.
Sounds very much like the forces exerted by the cyclist on STI levers to me. So STI's are alright, the bar clamp is alright but the bar bag clamp isn't. :?

I don't have the definitive answer to this, but there is still a lot of superstition surrounding carbon. Understandable perhaps, but doesn't help broaden the knowledge of the material.

teh

Re: barbags and carbon handlebars

Postby teh » 24 Oct 2013, 1:40am

I've had bars fail on me twice. Both times, I got a hint of what was about to happen, just before the ultimate failure. Had the bars been steel, the "hint" would have been better. Had the bars been carbon, I'm not sure I'd be here to offer this sage advice.

So, as far as carbon bars are concerned, I would definitely not use them outside their test regime.

The Mechanic
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Re: barbags and carbon handlebars

Postby The Mechanic » 24 Oct 2013, 2:17pm

I believe some carbon bars state that they are safe to use with clip on tri bars. I would expect they would also be OK with a bar bag.
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[XAP]Bob
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Re: barbags and carbon handlebars

Postby [XAP]Bob » 24 Oct 2013, 4:04pm

The issue with the stem clamp is that it always going to be in the middle, so the carbon will be beefed up, or supplemented with metal, in that section.
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beetroot
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Re: barbags and carbon handlebars

Postby beetroot » 25 Oct 2013, 8:57pm

foxyrider wrote:Because the bar is designed for that, its not designed to have something wrapped around it with a bunch of weight constantly jumping up and down against it.

I stick by my advice.


You mean like a pair of hands, and weight of the rider?