Seatpost binder bolt unusual
#1
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Seatpost binder bolt unusual
Has anyone ever seen this type of seatpost binder bolt? Can a different more standard one be used here ? There is no slit in the seat tube that can be clamped down on.Thanks in advance
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There are usually more than one reason why a design isn't used commonly. In this case the lesser ability to hold the post in place, compared to the usual slotted clamp design, is likely a big reason. Just look at the surface contact area of this design and look at a common slotted clamp and think about the huge difference. Less contact surface area means greater pressure will be needed for the same ability to hold the post.
This pinching internal binder has been done quite a few times over the bike industry's history. A well known version is the Fregus from the 1960s and 1970s. Try to find a replacement binder bolt set these days, oh and you better know which subtly different version your bike needs. Andy
This pinching internal binder has been done quite a few times over the bike industry's history. A well known version is the Fregus from the 1960s and 1970s. Try to find a replacement binder bolt set these days, oh and you better know which subtly different version your bike needs. Andy
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AndrewRStewart
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I hope the carbon post has been designed with the pinching binder in mind. Carbon isn't best used when localized compressive forces are at play. Andy
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AndrewRStewart
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#9
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There are usually more than one reason why a design isn't used commonly. In this case the lesser ability to hold the post in place, compared to the usual slotted clamp design, is likely a big reason. Just look at the surface contact area of this design and look at a common slotted clamp and think about the huge difference. Less contact surface area means greater pressure will be needed for the same ability to hold the post.
This pinching internal binder has been done quite a few times over the bike industry's history. A well known version is the Fregus from the 1960s and 1970s. Try to find a replacement binder bolt set these days, oh and you better know which subtly different version your bike needs. Andy
This pinching internal binder has been done quite a few times over the bike industry's history. A well known version is the Fregus from the 1960s and 1970s. Try to find a replacement binder bolt set these days, oh and you better know which subtly different version your bike needs. Andy
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This binder doesn't look too hard to make. A motivated person with basic metal working skills and tools (Tap, drill, file, hack saw) could do it. A machine shop would likely do it nicer and want more than a few dollars. If you're near Rochester, NY drop me a PM. Andy
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AndrewRStewart
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This binder doesn't look too hard to make. A motivated person with basic metal working skills and tools (Tap, drill, file, hack saw) could do it. A machine shop would likely do it nicer and want more than a few dollars. If you're near Rochester, NY drop me a PM. Andy
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Please do who ever has to duplicate this binder and record the dimensions and take better photos for reference. Otherwise a fairly simple fab job turns into a bigger design and hope it works one. That bigger job will be best done with the frame in the hands of the fabber. Andy
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AndrewRStewart
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The seat post that came with the frame is a Look product. I have owned 3 Look frames that used the same seat post and binder bolt arrangement. I assume that Look knows what they are doing
#16
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Do you have a picture of that bolt ? Does it look (no pun intended)like the one I have or is completely different?I am not planning on using a carbon seatpost but am still curious.