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Snapped frame do you trust carbon!

Westy

the teste
Nov 22, 2002
56,222
22,257
Sleazattle
I think this gets overstated a bit when it comes to bike manufacturing. Aluminum alloy frames have a lot of areas to have manufacturing defects as well, there's probably more recalled aluminum frames than carbon out there. It turns out to be "easy" to forget to weld all the way around the headtube (the way the downtube, headtube and top tube come together and are welded turns out to be important), or drilled some extra vent holes, or "forgot" to heat treat the frames again after a thermal event that would weaken them. As price for aluminum frames went down, some of the fine art/attention to detail/process control gets lost in the higher volume facilities.
Imagine how many "forgot to" opportunities there are when someone is hand placing hundreds of pieces of carbon fiber into a mold, with no easy way of seeing if something is wrong once the next layer is applied.

I have worked on large automated composite layup machines. They are significantly more repeatable than any human would ever be and have automated quality control systems, rework is regularly required. These have complex heating systems that closely controls temperatures ensuring there are no wrinkles or voids.

If you looked at the pictures from the GG auctions you can see they had people laying things down with an office projector and a hair dryer.

An advanced manual cell could have an overhead laser projector with an imaging system to check that every layer is in the correct position, but I suspect that isn't the case for bikes. Even then that can't ensure layers are compacted properly.
 
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Gary

my pronouns are hag/gis
Aug 27, 2002
8,594
6,494
UK
Another thing to be considered: Metal can be recycled, carbon and plastic can't.
Carbon can be infinitely repaired tho.
Recycling a rusty/fatigued old bicycle frame isn't exactly saving the world.
And buying a new one every five minutes because "geometry changed 5mm" certainly isn't.
 

Jm_

sled dog's bollocks
Jan 14, 2002
20,381
10,852
AK
Another thing to be considered: Metal can be recycled, carbon and plastic can't.
It can and it is. They are just now starting to spool up large scale operations for things like wind turbines, some CF some GF, but basically both can be recycled into CFRP and GFRP.
 

William42

fork ways
Jul 31, 2007
4,026
784
Another thing to be considered: Metal can be recycled, carbon and plastic can't.
Eh...

While technically true, the complete carbon cost of the product from start to finish of it's life cycle isn't dramatically different, and bicycles are a drop in the ocean compared to the big kahuna of waste that are the big industries.

I wouldn't lose any sleep over pretty much whatever material choice you want to go with.

Also, @Gary while I don't disagree that keeping bikes longer is a way bigger plus for the environment than whatever material you want to build your bike out of, I think the current topic of discussion is 'how do I get a bike that wont break and will last long enough for me to do that?'
 

joeg

I have some obvious biases
Jul 20, 2011
202
148
Santa Cruz CA
Imagine how many "forgot to" opportunities there are when someone is hand placing hundreds of pieces of carbon fiber into a mold, with no easy way of seeing if something is wrong once the next layer is applied.

I have worked on large automated composite layup machines. They are significantly more repeatable than any human would ever be and have automated quality control systems, rework is regularly required. These have complex heating systems that closely controls temperatures ensuring there are no wrinkles or voids.

If you looked at the pictures from the GG auctions you can see they had people laying things down with an office projector and a hair dryer.

An advanced manual cell could have an overhead laser projector with an imaging system to check that every layer is in the correct position, but I suspect that isn't the case for bikes. Even then that can't ensure layers are compacted properly.
The insight I shared comes from years making lots of different frames and components at different suppliers and doing a bunch of testing and seeing warranty data on said products over a decade. It does seem that theoretically there are lots of ways to fuck up making carbon bits, but in practice carbon manufacturing defects seem to account for fewer failures than composite design errors, or for aluminum manufacturing errors.
 

SylentK

Turbo Monkey
Feb 25, 2004
2,656
1,099
coloRADo
1: offer me a chainstay to buy
= I'm cool with that

2: don't tell me to buy another bike 20% off
= I don't buy a new truck cause it broke and axle
Just carry spare parts readily available especially if your stays are known to break...
Is that really their posture? And by that I mean their way of business. And this is Trek?
 

bullcrew

3 Dude Approved
Is that really their posture? And by that I mean their way of business. And this is Trek?
100% Trek
Yes...that's what they said... There was a stay available back east the tech at shop found I even told him I'd buy it... It was available for sale ..not as warranty in computer...

Then I called , hadn't heard anything... I called and he said "they won't warranty it, said buy a new frame 20% off"..The tech went to bat regarding it again and said sell him a stay "crickets".. so I'll call tomorrow
 
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SylentK

Turbo Monkey
Feb 25, 2004
2,656
1,099
coloRADo
100% Trek
Yes...that's what they said... There was a stay available back east the tech at shop found I even told him I'd buy it... It was available for sale ..not as warranty in computer...

Then I called , hadn't heard anything... I called and he said "they won't warranty it, said buy a new frame 20% off"..The tech went to bat regarding it again and said sell him a stay "crickets".. so I'll call tomorrow and show them pics of a snapped slash + less than a battery ride in and in the identical spot and there immediate call tag to get it to the factory immediately..they sent him a brand new frame, I don't want that...hell I just want to purchase the part at a crash replacement cost...
.then let them know I don't need a free part just sell the shit that can break...not a new bike...

Yeah I'm a bit irritated and it's pissing em off more and more...
Hmm...I'd say that's an interesting way of doing business.

Ahh Bike Industry: :You can do better.
 

Jm_

sled dog's bollocks
Jan 14, 2002
20,381
10,852
AK
100% Trek
Yes...that's what they said... There was a stay available back east the tech at shop found I even told him I'd buy it... It was available for sale ..not as warranty in computer...

Then I called , hadn't heard anything... I called and he said "they won't warranty it, said buy a new frame 20% off"..The tech went to bat regarding it again and said sell him a stay "crickets".. so I'll call tomorrow
Give em hell
 

bullcrew

3 Dude Approved
Anyone else find it hilarious that DH riders are putting lead weights on their Carbon bikes?
So what I need to pull the tire weights from my BB area???
Lol not kidding

Canfield short cranks going on and already coil shock and avy coil fox 40 up front ...sits just suv 38...want 38+ ..so weights it is...
..

Got my ass handed to me like a pingpong ball and not a Tijuana pingpong ball and ass style show either...

I read through the stuff and it's where I've been staying Enduro 36-40 DH 37+-44lbs...

It just rides better and less kick when you play Hellen Keller with rocks..


This is all and well the carbon thing but I'm not sure I'm 100% for hard material and rocks...strong yes hard no ...a dent is easier but when carbon hits it's threshold it shatters...hydro formed thin wall Pringles can crap I don't trust either...
 

Jm_

sled dog's bollocks
Jan 14, 2002
20,381
10,852
AK
Got a crash replacement coming in It's going to cost me a bit , but at least it's getting resolved I don't mind I just want it back up and running
Sou you bought the crash replacement frame?
 

englertracing

you owe me a sandwich
Mar 5, 2012
1,687
1,181
La Verne
So what I need to pull the tire weights from my BB area???
Lol not kidding

Canfield short cranks going on and already coil shock and avy coil fox 40 up front ...sits just suv 38...want 38+ ..so weights it is...
..

Got my ass handed to me like a pingpong ball and not a Tijuana pingpong ball and ass style show either...

I read through the stuff and it's where I've been staying Enduro 36-40 DH 37+-44lbs...

It just rides better and less kick when you play Hellen Keller with rocks..


This is all and well the carbon thing but I'm not sure I'm 100% for hard material and rocks...strong yes hard no ...a dent is easier but when carbon hits it's threshold it shatters...hydro formed thin wall Pringles can crap I don't trust either...

Well when you arent blind and hop and skip those rocks a 33lb enduro and 35lb dh bike sure whip, scrub flat, and table top easier...