Carbon seatpost strength
#27
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Carbon posts, handlebars, and forks do very well under routine stress. But, tighten a seat clamp too much, tighten a stem bolt too much, hit a pothole at high speed...carbon fails, and it fails instantly.
But, carbon is light, cool, and your neighbor can't afford it. Aren't those things more important than your health or life?
But, carbon is light, cool, and your neighbor can't afford it. Aren't those things more important than your health or life?
#28
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Originally Posted by Machka
The snapped forks I saw broke under a guy who wasn't very big ... and who was riding downhill on a very smooth road. He was hospitalized.
That's two carbon failures (my seatpost and his forks) I've seen in less than a year ... and enough for me to consider carbon as a non-viable material for a bicycle.
That's two carbon failures (my seatpost and his forks) I've seen in less than a year ... and enough for me to consider carbon as a non-viable material for a bicycle.
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Think of it this way--carbon is a material you're not supposed to a.) Clamp, and b.) Grease. What sense does it make to use it for a part whose basic function means wrapping a clamp around it and will only stop creaking in many frames if you smear grease on it? Carbon seatposts are an example of consumer stupidity and manufacturer dishonesty.
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I just replaced my seatpost on my Trek 7.5 FX disc with a carbon one. The carbon didn't really feel any lighter even though it's about 6 inches shorter. It does look better though.
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Originally Posted by trekkie820
The seemingly sporadic faliure of carbon fiber has got to be either misuse or manufacturing defects, not a flaw with the material itself.
#32
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How about a carbon/aluminum post? My Felt has a 'carbon' seatpost, but also says 6061 on it... is this just an aluminum post wrapped in carbon to look 'blingy?'
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CR-wrapped Alu is a good thing. Wasn't that how the early bars were done? And a lot of CF forks? That seems to be an ok combination. Take the best qualities of both materials, and combine them into one strong and light part that offers damping.
#34
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Im 5'11 155lbs. broke a very expensive selcof. was replaced under warranty. its sitting on my desk now. do i dare put it back in I'm pretty sure I will......
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Originally Posted by Jim Bonnet
Im 5'11 155lbs. broke a very expensive selcof. was replaced under warranty. its sitting on my desk now. do i dare put it back in I'm pretty sure I will......
#36
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Originally Posted by MERTON
you don't know about carbon wheels? where have you been?
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Weather today: Hot. Humid. Potholes.
Weather today: Hot. Humid. Potholes.