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Ridden my carbon fatbike at -36C. Just fell apart like it was made from spaghetti....


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EAT MORE GRIME
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Not a carbon expert, but lots of airplanes both commercial and military are built using carbon fiber, which at extremely high altitudes are subject to extremely low temps.
planes often go from 100 deg tropical humidity to -60 degrees in 30 minutes, and the only problem CF airplane parts have is if there is an existing defect allowing water in the layup. [bikes can't come anywhere close to those temperature extremes unless it is in the cargo bay of an airliner]
 

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Elitest thrill junkie
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[bikes can't come anywhere close to those temperature extremes unless it is in the cargo bay of an airliner]
The cargo bay of an airliner is kept above freezing. Think of the dogs.
 

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the only issue you will have with cf frames and cold might be water ingress into the layup due to defects around water bottle bosses or any other part of the frame if water can get in there and freeze

if clean and dry, you are fine

https://www.youtube.com/watch?v=JNd8MoWRnr8
This does make sense. Anecdotally I've ridden nine winters on a CF frame with various amounts of water in it, some of which was saline, some not, due to my substandard winter bike care, which consisted of spraying it with a hot water hose.

I've had the rivets for a few water bottle bosses and cable guides corrode and give out, but nothing that was too difficult to fix.

In the winter of 2013 when it was constantly -20C or lower, I was having trouble steering, which I blamed on the headset grease thickening in the cold.... until I took the headset apart to degrease/regrease, and a quarter cup of water came out. So... no grease alteration was required.
 

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Discussion Starter #26
Thanks for all the replies. I really did not consider temperature as a detractor for any bicycle frame material. But when the majority of people keep bringin it up, sometimes you second guess yourself.
 

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nah it's all good,

it is water where it ain't 'sposta be which is the killer in cold, not the frame itself
 

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Nope, on some planes there are multiple bays and not all are always temperature controlled or adequately pressurized.

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Unless you are talking about a piper navajo and wing lockers, no. The cargo hold of an airliner/cargo aircraft has to be pressurized for structural integrity of the fuselage, and then the bleed air is naturally hot, mixed with cooler air, but kept above freezing. If not adequately pressurized, the in “some sections”, the fuselage would collapse like stomping on an empty soda can. Small cargo planes like a Cessna 208 wont give enough time to cold soak the cargo except in extreme situations.

This is generally untrue and not a concern (that cargo freezes on the plane). I kinda have to know this for work. ;)
 

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Unless you are talking about a piper navajo and wing lockers, no. The cargo hold of an airliner/cargo aircraft has to be pressurized for structural integrity of the fuselage, and then the bleed air is naturally hot, mixed with cooler air, but kept above freezing. Small cargo planes like a Cessna 208 wont give enough time to cold soak the cargo except in extreme situations.

This is generally untrue and not a concern (that cargo freezes on the plane).
Again incorrect, there are multiple confirmed instances of animals dying in the hold due to temperature extremes, both hot and cold, as well as inadequate pressurization of the hold. Now if you are talking exclusively commercial that is a different conversation with regards to pressurization. Inadequate does not equate to none.

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well FFS folks, the point is, CF composites don't require much more than perfect engineering and layup (no defects) to survive wild temperature swings from hot tropical air (100 deg or more) to far below zero (-60F) in 30 minutes, or less. well laid up CF handles this fine

your bike will not experience anywhere near the extremes CF breezes through on a regular basis.

Now, if your bike frame is full of voids, defects, too much or too little resin, water got in there....all bets are off. water freezing and thawing for a winter can turn your frame to dust if it has invaded the layers
 

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Again incorrect, there are multiple confirmed instances of animals dying in the hold due to temperature extremes, both hot and cold, as well as inadequate pressurization of the hold. Now if you are talking exclusively commercial that is a different conversation with regards to pressurization. Inadequate does not equate to none.

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You said an airliner. The pressure vessel HAS to pressurize evenly. Unless there is an aircraft accident, the pressure is adequate. Same for temps, they are kept above freezing. You will die with enough time at 40 degrees, but you won’t freeze. Show me exactly what scenario where cargo is being subject to extreme cold temperatures. What aircraft?
 

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You said an airliner. The pressure vessel HAS to pressurize evenly. Unless there is an aircraft accident, the pressure is adequate. Same for temps, they are kept above freezing. You will die with enough time at 40 degrees, but you won’t freeze. Show me exactly what scenario where cargo is being subject to extreme cold temperatures. What aircraft?
Getting a little off topic?

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You said an airliner. The pressure vessel HAS to pressurize evenly. Unless there is an aircraft accident, the pressure is adequate. Same for temps, they are kept above freezing. You will die with enough time at 40 degrees, but you won’t freeze. Show me exactly what scenario where cargo is being subject to extreme cold temperatures. What aircraft?
Yes, I said airliner. You know, the type of aircraft used for transporting passengers and cargo? It can be any aircraft with zoned holds for any number of reasons. HVAC malfunction, inattentiveness by the crew to turn the switch on, etc.

Here is just one incident, http://avherald.com/h?article=48c6c1aa&opt=0, luckily the captain caught it and diverted due to knowing an animal was below. That does not always happen. Additionally, if you read to the end it makes no mention of the heater being repaired but that the dog and owner boarded another plane and the original continued on to its destination making it easy to draw an inference that it continued on with an unoperational hold heater it that section.

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Yes, I said airliner. You know, the type of aircraft used for transporting passengers and cargo? It can be any aircraft with zoned holds for any number of reasons. HVAC malfunction, inattentiveness by the crew to turn the switch on, etc.

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Um, yeah...it doesn’t really work like that. I’m going to chalk this up to old wives tales. It’s a myth with few exceptions that the cargo holds on airliners aren’t pressurized or temp controlled. Those articles are simplified and not the full information, there is no “heater”, there’s hot bleed air from the engines and then heat exchangers that mix it with cooler air, valves and other components. Likely a failure of one of the heat exchanger “pacs” or associated valves, but above all pressurization has to be maintained for structural integrity. In any case, that’s an outlier and no extremes were even experienced. People think the cargo holds are at -60 and unpressurized.
 

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Um, yeah...it doesn’t really work like that. I’m going to chalk this up to old wives tales. It’s a myth with few exceptions that the cargo holds on airliners aren’t pressurized or temp controlled.
I mean when you cut out the article from my post that describes one scenario where it can, and actually did, happen I guess you can come to that conclusion.

I'd also suggest looking into the An-124 and 747-400 for starters...

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Jayem and tuckerjt07; You two are positively the most airplanest MF'ers on the forum. Nobody, and I mean NOBODY, airplanes any harder than you two guys. Equally. Perfectly even. I-----dentical! Are we cool now?

Oh, and your names were listed in alphabetical order, so there.




By the way, you guys hear they started making those things out of carbon fiber? Crazy that bike part material is trickling up into everything these days.
 

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I mean when you cut out the article from my post that describes one scenario where it can, and actually did, happen I guess you can come to that conclusion.

I'd also suggest looking into the An-124 and 747-400 for starters...

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How are you traveling with your bike on an all-cargo 124? Even the 747-400F has temperature controlled cargo holds.
 

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Www.bike-flights.com


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You do realize those airplanes are for specialized heavy-lift contracts, right? And I don’t mean specialized bikes.

Get over it, you posted a common myth about air cargo.

All of the 748-400F operators I have checked advertise temp control between 4-30 degrees C for cargo btw.
 
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