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Old 08-18-06, 08:12 AM   #1
krazygluon
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Bent seatpost: causes, prevention and repair?

Preface: this is an old steel road bike, and i'm pretty sure its a 7/8" (21.13 mm?) seatpost.

As I got more and more into cycling, I realized my seatpost was too low. I finally got it into a good position, leveled out the saddle and everything went fine for about a week.

then I converted the bike to single speed and something happened: my seatpost started to bend!
Its sitting right at the max height line, so i'm not exactly going beyond what it was supposedly designed for, but wth? I'm guessing that in switching to single-speed, I do a lot more pulling of the pedals (I do ride clipless) and its the pull added to my 240lbs of lard-butt that's doing the bending.

my question is, 1) have other clydeish riders experienced this and 2) how do I prevent it, a longer seatpost so I have more of it in the frame at the height i need?

also, is any specific seatpost material less prone to bending? this one looks like aluminum, but given its age, I'd say its not a very good alloy.
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Old 08-18-06, 03:05 PM   #2
bOsscO
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also, is any specific seatpost material less prone to bending? this one looks like aluminum, but given its age, I'd say its not a very good alloy.
Well aluminum usually doesn't bend: it breaks. So it maybe cro-mo or something, I don't know. I've bent a post before but due to a crash (in teh dark, a chain across a shool drive way is almost invisible btw). If the bend is where the post meets the frame, then it's probably your belly. if it's bending anywhere else, then the post has just had it's day.
Yes! a longer post will help you out (more in the seat tube = less leverage at clamp) or a larger diameter post...but that requires a larger diameter frame
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