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  1. #1
    Newbie C-daleRider's Avatar
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    28.6-31.6 Seat Post Shim

    Hey Just wondering if anybody new how to make one because apparently they aren't availbale to purchase? p.s. I want to make sure it's reliable and safe thanks.

  2. #2
    coprolite fietsbob's Avatar
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    1.5 mm thick shim stock .. that is the difference between the 2 , rolling it around the post = 3mm ,
    the diameter difference in question..
    Vernier Micrometer caliper is useful in measuring these sort of thin materials..
    wall thickness of a tube is a radial measurement .. 2r=D

  3. #3
    cab horn
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    http://wheelsmfg.com/content/view/529/41/

    why don't you just buy a 31.6 seatpost? They exist, thomson et al. 28.6 is also another unusual size.

    Pre-manufactured shim will take a 31.6 to a much more common 27.2 size. Do that.
    Mes compaingnons cui j'amoie et cui j'aim,... Me di, chanson.

  4. #4
    Newbie C-daleRider's Avatar
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    Quote Originally Posted by fietsbob View Post
    1.5 mm thick shim stock .. that is the difference between the 2 , rolling it around the post = 3mm ,
    the diameter difference in question..
    Vernier Micrometer caliper is useful in measuring these sort of thin materials..
    wall thickness of a tube is a radial measurement .. 2r=D
    Thanks fietbob for the lightening quick response and the helpful insights, I read that aluminum is the best matrial to use for this. Any advice on how to get the shim formed?
    Quote Originally Posted by operator View Post
    http://wheelsmfg.com/content/view/529/41/

    why don't you just buy a 31.6 seatpost? They exist, thomson et al. 28.6 is also another unusual size.

    Pre-manufactured shim will take a 31.6 to a much more common 27.2 size. Do that.
    Thats true that regular post exist, but suspension seat posts in a 31.6 dia. don't(with the possible exception of an awful looking device called a thud buster but it still might haved to be shimmed up). I want a suspension seat post that's as close the the diameter as possible. When I purchased my bike I was naive and thought suspension seat posts were availble in all sizes. p.s. a 27.2 looks like a tooth pick when coming out of a 31.6 tube.

  5. #5
    cab horn
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    Quote Originally Posted by C-daleRider View Post
    p.s. a 27.2 looks like a tooth pick when coming out of a 31.6 tube.
    This requirement makes no sense. Aesthetically a suspension post in of itself is a fail already
    Mes compaingnons cui j'amoie et cui j'aim,... Me di, chanson.

  6. #6
    Newbie C-daleRider's Avatar
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    No requirement, and there are different levels of ugly. Doing this for comfort/health reasons only.

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