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  1. #1
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    What Post Length For a Med. Spot?

    For a 5'6"rider, what length post should I get? I'm thinking a 410 is required or was that on the small. This will be a temporary post until I figure out which Gravity Dropper I want (4" vs. 3" drop vs. multiposition vs. All the way down).
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  2. #2
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    It all depends on your inseam length, not your overall height.

    I'm 5'8"or so and I have long legs. My inseam (true inseam, not pants inseam) is 32.5". I need a post of at least 375mm on my medium spot. You'll most likely need less. Just calculate the difference betweeen my inseam and yours.... then subtract (assuming your inseam is less) that difference from 375mm and you'll have your minimum post length.

    My suggestion is to buy a 410mm post and don't cut it. A longer post is easier to sell than a shorter post. You can always cut it if you decide to keep it.

    btw.... I recommend the 4" drop, multiple position GD. I currently have the 3" drop version and am about to buy a new insert to allow a 4" drop. The multi-position is great. The 1" drop is perfect for fast singletrack or very technical climbs.

  3. #3
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    Here's a rough approximation (all in inches): [(true inseam x 0.88) - seat tube length] + 4"

    So on a medium Spot that would be: (true inseam x 0.88) - 13
    "The best you've ridden is the best you know" - Paul Thede, Race Tech

  4. #4
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    Oh, yes. I forgot the most important measurement-inseam. I'm at 28", 29" with shoes. So, with your formula, that would be a 12 1/2" post. That's 317.5mm, so a 330mm post is good.

    4" GD, huh? Sounds good. I like the idea of a 1" drop for technical climbs, though I've always just ran my post full height for all climbs. I think I'll try it.
    Last edited by myitch; 05-17-2006 at 04:26 PM.
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  5. #5
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    Quote Originally Posted by myitch
    Oh, yes. I forgot the most important measurement-inseam. I'm at 28", 29" with shoes. So, with your formula, that would be a 12 1/2" post. That's 317.5mm, so a 330mm post is good.

    4" GD, huh? Sounds good. I like the idea of a 1" drop for technical climbs, though I've always just ran my post full height for all climbs. I think I'll try it.
    Sounds about; right.

    I also recommend the 0", -1" & -4" multiposition GD.

    If you've made your decision on the GD then save some money and buy the GD instead of a regular post and GD.
    "The best you've ridden is the best you know" - Paul Thede, Race Tech

  6. #6
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    Quote Originally Posted by myitch
    For a 5'6"rider, what length post should I get? I'm thinking a 410 is required or was that on the small. This will be a temporary post until I figure out which Gravity Dropper I want (4" vs. 3" drop vs. multiposition vs. All the way down).
    what is the source of 410mm being "required"? I've never heard that.

    seatpost length is a feature of your saddle height on a given frame. I am unclear as to why you would insist on a 410mm post if you don't need that much exposed post. someone on the shorter end of a frame's suggested rider height would not be likely to need 410mm of post... i.e., someone who's 5'6" on a Medium isn't likely to need more than 350mm of post, might not even need that much.

  7. #7
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    Quote Originally Posted by myitch
    So, with your formula, that would be a 12 1/2" post. That's 317.5mm, so a 330mm post is good. .
    Play it safe and get a post that is at least 350mm. I little too long is not an issue.

    Quote Originally Posted by myitch
    4" GD, huh? Sounds good. I like the idea of a 1" drop for technical climbs, though I've always just ran my post full height for all climbs. I think I'll try it.
    You'll love it. Here's a suggestion.

    If you want to use the GD on more than 1 bike.... Order the post for the larger of the 2 diameters. The Turner needs a 27.2. If the other bike is a 31.6, for example, then they'll send you a 27.2 GD with a 31.6 shim for free. Now you can use it on 2 bikes for no additional cost. I thought of that AFTER I ordered it for my Spot. I just purchased a shim for my other bike for $4 plus shipping. A fair price indeed.

    EDIT: I just received my 31.6 shim and it's only 2" long. Make sure that you order the Long Shim (4"). I don't understand why they would even consider supplying a 2" shim for any bike. 2" is not enough post insertion for any bike that I have ever been on.... or know about. No big deal, though. I called them up and the longer one is in the mail. They're great people to deal with at GD.
    Last edited by Blue Shorts; 05-18-2006 at 01:16 PM.

  8. #8
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    The GD in -1 is great for technical climbing. Especially for long legged people. You can keep just enough post up to still have pedal leverage but have enough manuvering space for all kinds of body english w/o the seat getting in the way. I don't use it this way all the time but there are definately times when I appreciate it as a climbing tool.

    Whatever length you decide on, consider how high your seat is now (collar to rails), and make sure your post is long enough to have 4" inserted in the seat tube. Preferably meeting the TT/ST junction. The ST flares out after the junction so post past that point just hangs there.

    Quote Originally Posted by Blue Shorts
    I'm 5'8"or so and I have long legs. My inseam (true inseam, not pants inseam) is 32.5".
    (chuckle) Maybe you could ask SS to have you fitted for a blue suit and white hat ... I got 38.5" on all three legs.
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