Damaged carbon frame

Richridesmtb

Member
Jan 23, 2022
207
96
Australia
I'm pretty certain you've made the right choice. I hope I don't find myself in your situation, as I live in a country where I would have to drive the distance of a small country to find a carbon fibre repairer.
 

Longfellow78

Active member
Jan 4, 2022
284
116
Hampshire
I've done the tapping test thing already and didn't notice a change of sound. It looks there is no damage to the carbon itself.
My fall was more of a slide in a field , it was so slippery and muddy that the rear wheel went slowly sideways till the point I was totally lying on the ground and sliding with the bike on a few meters. So no real hard knock on the frame (I think!).

Safest option is unfortunately out of my budget! All this COVID thing killed it...

Luckily, in regards of this small country that is Belgium, I found a carbon specialist near my place and I will definitely pay him a visit to fix this.
Make sure you keep us updated on the repair!
 

paske

Member
Apr 2, 2021
47
33
Belgium
Make sure you keep us updated on the repair!

I will but it it will take some time.
I go to the hospital tomorrow for an operation and will be out both riding and working for a month!
During this month as soon as I can lift a little bit of weight, I will go to the carbon specialist.
 

Gary

Old Tartan Bollocks
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Mar 29, 2018
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I'm pretty certain you've made the right choice. I hope I don't find myself in your situation, as I live in a country where I would have to drive the distance of a small country to find a carbon fibre repairer.
A country with no postal service?
Interesting 🤔
 

DarrenCC

Member
Apr 3, 2021
61
22
Hertfordshire
As already stated by others, Carbon repairs are often stronger than the original tube and are invisible after a respray.

DON’T SPRAY WD40 ON IT

Penetrating oil potentially getting into the Carbon fibres may render it much harder to repair 😬
Good luck
 

Mybrainaches

Member
Jan 27, 2019
45
33
Sheffield
This makes zero sense, but okay. I don't think a rock differentiates if a bike has a motor or not, but that's my thinking.
The reason for a carbon bike is principally to save a few grams. On an ebike this is offset by the motor, so for me the advantage of an alloy frame having a less catastrophic mode of failure is more important than saving weight. Does that clarify my position to you?
 

Chicane

Active member
Nov 11, 2020
364
318
SoCal
The reason for a carbon bike is principally to save a few grams. On an ebike this is offset by the motor, so for me the advantage of an alloy frame having a less catastrophic mode of failure is more important than saving weight. Does that clarify my position to you?
Makes since for most Ebikes, but not quite as much in the light weight Ebike forum.
 

Gary

Old Tartan Bollocks
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Carbon has many more advantages over Alu than simply weight savings as a frame material for a bike which has a motor bolted on and a battery inside it.
Carbon is also much more repairable when the frame is damaged.
But just ignore these facts if it makes you feel better.
 

jimbob

Active member
Aug 3, 2020
523
433
East UK
Carbon has many more advantages over Alu than simply weight savings as a frame material for a bike which has a motor bolted on and a battery inside it.
Carbon is also much more repairable when the frame is damaged.
But just ignore these facts if it makes you feel better.
Could I ask what the additional advantages are? I (perhaps wrongly) assumed that an aluminium frame would be stronger and last longer?
 

Gary

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Their strength properties simply differ. Carbon can be stronger in many ways and can be designed to be stiffer and lighter or less stiff but stronger.
Carbon can have a longer life than welded Alu accidental damage excluded.

Some here should think about doing a little research before making unfounded claims about materials.
 

geehaw

Active member
Nov 17, 2019
107
86
Melbourne Australia
Could I ask what the additional advantages are? I (perhaps wrongly) assumed that an aluminium frame would be stronger and last longer?
Carbon can be layered to provide stiffness in one direction while providing more flex in another direction. A properly designed carbon frame bike should provide better handling characteristics and less rider fatigue.
This is a great article about advantages and disadvantages of Carbon vs AL specifically on bike frames.
Carbon Vs Aluminum Bike Frame: Pros and Cons - Where The Road Forks
 
Last edited:

Rod B.

Well-known member
Aug 18, 2021
530
925
USA, Orange County Ca.
Hi,
Last ride I fell and now there is a big scratch on my carbon frame.
I have no idea what can I do or have to do to avoid that damage to extend more.
Any advice will be welcome, thanks. View attachment 82025 View attachment 82026 View attachment 82027

Paske,

I’m sorry to see the damage to your bike. Totally sucks my friend. You should not ride your bike
further in it’s current state. The damage looks severe.

The top tube is the main structural component on you frame. Additionally, the rear shock mounts in the area where the damage is. This area is under a lot of stress and a weakened top tube should not be taken lightly. If the top tube fails while riding, you could be badly injured when the frame collapses.

Carbon frame damage is much like an iceberg. You can see the tip, but the real mass is hidden below the water. What looks like superficial paint chipping on the frame may actually be fractured carbon fibers radiating out internally. Fractured carbon fiber has no strength.

Fortunately carbon fiber frames can be repaired and the paint expertly matched.

You have several options:

1) Strip all of the parts, wiring, battery, components off your current front frame triangle. Purchase a replacement frame from Orbea via your local Orbea dealer and put your parts on the new frame.

Most bike companies will sell you a replacement frame at a much discounted price. I’ve gone this route myself on one occasion. Unfortunately, Orbea has it’s hands full meeting orders right now. It may take a while to get a replacement frame.

2) Your other option is to take the stripped frame to a certified carbon frame repair specialist. Most frame repair specialists can match the frame paint so that there is no evidence of the damage. You want your baby to look good.

3) I do not presume to know your financial situation. Times are hard these days. If you do not have the funds to buy a replacement frame or the ability to pay for the services of a carbon frame repair specialist, you can do the repair yourself. Carbon fiber is much like working with fiberglass and resin.

NOTE: I would strongly caution against doing the repair yourself unless you are familiar with carbon fiber repair and have no choice due to finances. The consequences of a failed repair are extreme.

I saw on your profile that you are from Belgium. I took the liberty of looking for a Belgium based certified carbon frame repair and paint matching expert. I found the website listed below. I do not know anything about these people. I attach it to let you know that there are services available near you.

 

Mikerb

E*POWAH Elite World Champion
May 16, 2019
6,581
5,068
Weymouth
Paske,

I’m sorry to see the damage to your bike. Totally sucks my friend. You should not ride your bike
further in it’s current state. The damage looks severe.

The top tube is the main structural component on you frame. Additionally, the rear shock mounts in the area where the damage is. This area is under a lot of stress and a weakened top tube should not be taken lightly. If the top tube fails while riding, you could be badly injured when the frame collapses.

Carbon frame damage is much like an iceberg. You can see the tip, but the real mass is hidden below the water. What looks like superficial paint chipping on the frame may actually be fractured carbon fibers radiating out internally. Fractured carbon fiber has no strength.

Fortunately carbon fiber frames can be repaired and the paint expertly matched.

You have several options:

1) Strip all of the parts, wiring, battery, components off your current front frame triangle. Purchase a replacement frame from Orbea via your local Orbea dealer and put your parts on the new frame.

Most bike companies will sell you a replacement frame at a much discounted price. I’ve gone this route myself on one occasion. Unfortunately, Orbea has it’s hands full meeting orders right now. It may take a while to get a replacement frame.

2) Your other option is to take the stripped frame to a certified carbon frame repair specialist. Most frame repair specialists can match the frame paint so that there is no evidence of the damage. You want your baby to look good.

3) I do not presume to know your financial situation. Times are hard these days. If you do not have the funds to buy a replacement frame or the ability to pay for the services of a carbon frame repair specialist, you can do the repair yourself. Carbon fiber is much like working with fiberglass and resin.

NOTE: I would strongly caution against doing the repair yourself unless you are familiar with carbon fiber repair and have no choice due to finances. The consequences of a failed repair are extreme.

I saw on your profile that you are from Belgium. I took the liberty of looking for a Belgium based certified carbon frame repair and paint matching expert. I found the website listed below. I do not know anything about these people. I attach it to let you know that there are services available near you.

I have said all of this before on another thread but I guess it is worth repeating here.
Fabricating carbon composite tubes and then joining those tube together is a labour intensive and highly skilled job. The strength and integrity of the finished product is dependant on a lot of factors, most of which are not disclosed by the bike brands. Merely calling a frame carbon tell you nothing. There are several different carbon mat formats....UD, Matrix etc. It does not even specify it is 100% carbon so the composite layers used could comprise a mix of fibres.....carbon, glass, kevlar etc. The type of epoxy used is never specified. It is not even specified if the constrcution method is wet lay up or pre preg. It does not tell you what modulus carbon is used.
In other words, you buy a carbon framed bike and you do not what it is made of, how it is made, who made it, what their experience is.
What you do know is that quality control is likely to be highly variable, and carbon composite, whilst it can be made very stiff on a directional basis, is invariably brittle. Carbon composite does not deform ( ie dent). It can be made with a certain degree of reflex.....that is it deforms slightly and rebounds, but it is impossible to tell without xray equipment whether that impact has caused delamination and/or fracture of carbon threads at some point in the composite. In most case carbon composite tubes are joined by a male/female joint and stuck with epoxy. How that joint is made more attractive is either through wet laying further layers around the joint or just filler. 3 way joints are highly complex areas to make look smooth. Anything mounted in a carbon composite frame needs metal inserts laid into the composite. Reinforcement around those inserts and ensuring the composite is unable to flex in ANY direction around those inserts is very important.

Not knowing virtually anything related to the above is one reason I would not buy a carbon framed bike for mountain biking. The performance of the construction is impossible to determine without that knowledge. It may be overly stiff, it may be too flexible, it may be badly designed and/or constructed. By way of contrast ,hydro extrusions are la argely automated process, enabling ally tubes to form the most beneficial shape and thickness at different points in the tube to balance weight with strength/stiffness in multiple axis. The welding together of the component parts is automated and you can see the quality of the welds ( if you know what you are looking at!). Ally tubes are strong and can deform ( dent) often without significant impact on the strength of the tube.....and can be repaired. The raw materials and construction process is lower cost and repeatable with high levels of quality control. It is also recycleable.

Ally for me everytime for mtb.
 

KnollyBro

E*POWAH Elite World Champion
Dec 3, 2020
1,004
2,348
Vancouver
"It is also recycleable."

But not many bike manufacturers consider the carbon foot print of making an aluminum frame vs. a carbon frame (I know Knolly does!) and where they will both ultimately end up (recycled vs landfill). My wife and I both have carbon frames and with out a side by side comparison with an aluminum frame, we are not at such a high level to notice a difference, on the trail (bank account - YES!!!). For those reasons, we would prefer to have aluminum frames as well but the emtb choices are limited.
 

Gary

Old Tartan Bollocks
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Mar 29, 2018
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Many bicycle frame manufacturers do actually stipulate exactly what grade of carbon their frames are made from and openly share what their manufacturing process involves.
 

Rusty

E*POWAH BOSS
Jul 17, 2019
1,513
1,673
New Zealand
Personally, even though I have destroyed a couple carbon fibre frames and many handlebars, will take it over aluminium alloy any day - not for the weight factor, but for the feel of the ride. I will accept an alloy rear triangle, but prefer carbon fibre for both triangles.

Back to the OP.
@paske - that should be repairable, but I would not recommend doing it yourself .... unless you have access to the proper scanning equipment. What I see in the original picture is that it has sustained an impact hard enough that could definitely cause fracturing of the fibre weave, or a delamination of the layers. Where that is, just back from the headset is not as highly stressed as if it was say the same distance from the seatpost, but it could fracture and fold at a very inopportune moment - especially if you ride gnarly trails with g-outs & jumps.
 

Mikerb

E*POWAH Elite World Champion
May 16, 2019
6,581
5,068
Weymouth
Personally, even though I have destroyed a couple carbon fibre frames and many handlebars, will take it over aluminium alloy any day - not for the weight factor, but for the feel of the ride. I will accept an alloy rear triangle, but prefer carbon fibre for both triangles.

Back to the OP.
@paske - that should be repairable, but I would not recommend doing it yourself .... unless you have access to the proper scanning equipment. What I see in the original picture is that it has sustained an impact hard enough that could definitely cause fracturing of the fibre weave, or a delamination of the layers. Where that is, just back from the headset is not as highly stressed as if it was say the same distance from the seatpost, but it could fracture and fold at a very inopportune moment - especially if you ride gnarly trails with g-outs & jumps.
no 2 carbon frames will feel the same, and no 2 ally frames will feel the same and I doubt if blindfolded you would be a ble to say which you are riding. The primary structional reasons for using carbon composites as opposed to glassfibre, aluminium or polyprop etc are to achieve exceptional stiffness together with lightweight and most often in extended flat panels since that is where achieving those objectives is mostly impossible with alternative materials.
A construction consisting jointed tubes is another story and carbon composite is not an obvious choice unless absolute stiffness and ultra lightweight were essential. The penalty in that case would be fragility any time it experienced an impact or a torsional force. That is an accepted risk in some race circumstances where longevity and cost are not important and/or where it is relatively easy to use the product a voiding the risk of impact.
An extruded ( ie seamless) ally tube already inherits the multi directional strength of a tubular shape. If you then add to that the selection of the best grade of ally ,e.g. 7075, which is lighter and stiffer than say 6061, and use the hydro forming extrusion method you can vary the shape, diameter and wall thickness of the tube at different points along its length, you can design in the required strength, stiffness or flex. There is little difficulty in designing strength or stiffness in a frame triangle except for torsional forces. In terms of stiffness that is where design rather than material makes a difference. Hence the actual weight differences between a modern ally frame and a carbon composite frame is marginal.
 

Rich-EMTB-UK

E*POWAH Master
Aug 11, 2019
369
283
UK
I've done the tapping test thing already and didn't notice a change of sound. It looks there is no damage to the carbon itself.
My fall was more of a slide in a field , it was so slippery and muddy that the rear wheel went slowly sideways till the point I was totally lying on the ground and sliding with the bike on a few meters. So no real hard knock on the frame (I think!).

Safest option is unfortunately out of my budget! All this COVID thing killed it...

Luckily, in regards of this small country that is Belgium, I found a carbon specialist near my place and I will definitely pay him a visit to fix this.
hopefully no damage to the carbon as you say but get it checked for your own peace of mind.
 

Rusty

E*POWAH BOSS
Jul 17, 2019
1,513
1,673
New Zealand
no 2 carbon frames will feel the same, and no 2 ally frames will feel the same and I doubt if blindfolded you would be a ble to say which you are riding.

We will have to agree to disagree. The way modern alloy frames are hydroformed should make them as close to identical as you could get. Only a change in the alloy batch could make any noticeable change as the jig settings don't change, the pressure used would only change if there was a leak and the way they are welded is electronically controlled. As far as telling the difference blindfolded - while I have attempted to ride a large dirt oval with a blindfold on I would not be trying to ride on a proper track.
However, I can hear and feel the difference between an alloy bike and a carbon fibre one. Have owned several models identical except for the frame material and always have been able to go faster for a longer period. Yes I can accept some is mental, but to me aluminium alloy frames on bicycles just don't feel right.
 

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