Lay back seatpost - with or without support?

Discussion in 'Motorized Bicycle General Discussion' started by Nougat, Sep 9, 2010.

  1. Nougat

    Nougat New Member

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    I've decided that I need a lay back seat post. Some of them have an extra support bar, and some don't. How important is that support? Take into consideration that I'm currently 210 lbs., and occasionally ride in gravel, and over rough roads. Has anyone ever unexpectedly bent an unsupported seat post?
     
  2. MotorBicycleRacing

    MotorBicycleRacing Well-Known Member

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    The first lay back seat post I tried came from Spookytooth.
    It had the extra support bar and it kinked like a pretzel after a few months?

    I weigh about 175 lbs and was carrying a 35lb? Nirve kids chopper on my
    shoulder when it started to noticeably bend.
    The seat post was about 2" above the minimum insertion mark.

    I have long legs and arms and really need the set back to be comfortable
    so I bought another one with the brace.
    This time I inserted the seat post another 1 1/2" so that the brace was
    as far down as it could be.
    I have put about 1700 miles on the bike and the post is starting to bend again.
     
  3. Venice Motor Bikes

    Venice Motor Bikes Custom Builder / Dealer/Los Angeles

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    I cut & weld my own lay back seat posts, & I weigh 210 lbs.
    I always insert a custom 'L' angle cut from 1/4" steel into the post before I weld it together! (I've had good luck with them so far.) ;)
     
  4. Nougat

    Nougat New Member

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    Venice, do you make those for sale? If so, how much for one (25.4mm) shipped to Chicago?
     
  5. Venice Motor Bikes

    Venice Motor Bikes Custom Builder / Dealer/Los Angeles

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    I usually charge $40 to make one, (1 hour labor)... PM me.
     
  6. chainmaker

    chainmaker New Member

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    You cant go wrong with a lay-back post for Me, it makes the ride so much more relaxed or (laid-backlaff)

    Cheers
     
  7. tvc15

    tvc15 New Member

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    Can we see one?
     
  8. sportscarpat

    sportscarpat Bonneville Bomber the Salt Flat record breaker

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    Lets face it, layback posts can bend. So far I have had good luck by being a little careful. The lower the post sits in the frame the stronger it is. Also don't lay them back too far. Its all about the overhung load and length of the leverage arm. Moving the seat back just 3" makes all the difference in the world. Moving it back 4-6" and you'll bend the post over time. Adding a gusset helps but then you can't move the seat post all the way down. They are cheap anyway, so if you bend one then buy another. Oh, starting with a good chrome moly post helps.
     
  9. bairdco

    bairdco a guy who makes cool bikes

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    nobody's mentioned riding style yet. a bicycle seat and post (not to mention your butt, spine, pelvis, etc...) is not designed to take heavy shockloads.

    look at the difference between motorcycle seats and the way they're mounted compared to a bicycle.

    you should be "unweighting" yourself when hitting bumps.

    that being said, i know there's always the unsuspected body jar out there, so if in doubt, go with the strongest possible.
     
  10. 2door

    2door Moderator
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    If you rely on a tubular seat post then bending it will always be a possibility. Like was said above, the longer it extends to the rear, the easier it will bend (more leverage)
    If you have access to a lathe and a source of heat you can fabricate your own post from solid bar stock. Most seat tubes will require a 1" seat post that tapers to 7/8" where the saddle mounts. I've made several with a lay back of six and seven inches. Never bent one yet. A friend in the metal working business would be a plus here if you don't have the necessary tools.
    Tom
     
  11. r00t4rd3d

    r00t4rd3d New Member

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    #11 r00t4rd3d, Sep 11, 2010
    Last edited: Sep 11, 2010
  12. azbill

    azbill Active Member

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    that's a cool seatpost :)
    thanks for the link ;)
     
  13. bluenosegoat

    bluenosegoat New Member

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    I cant ride a cruiser with out a laid back seat post. I weld in a support bar that goes to the brake mount so its verticle. No adjustment but I know where I like it and no one else rides my bike! I've made a few of these for cranbrooks I've sold- cant produce them though because every bike is different- even the cranbrooks vary (imagine that! quality control?)
     

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    #13 bluenosegoat, Sep 12, 2010
    Last edited: Sep 12, 2010
  14. silverbear

    silverbear The Boy Who Never Grew Up

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    On some of the old cruisers the seat post is an L shape and is solid steel. On my current Worksman NB build I used a 1942 Elgin seat and reversed the L so that in effect it is a layback post in that configuration. The diameter of the post is smaller than modern ones, so some shimming is required to make it work, which I did with a section of handlebar slit lengthwise in two, plus a section of copper water pipe also slit lengthwise. If you're after a vintage look it is one way to go.
    SB
     
  15. Venice Motor Bikes

    Venice Motor Bikes Custom Builder / Dealer/Los Angeles

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    Here's before & after pics of a customers bike that I built & later changed many of the parts for him... This seat post was one of the longer ones that I did & it's still working fine with no cracks or bending. (it has a 3"X3"X1/4" steel 'L' angle inserted into it before welding.)

    [​IMG]
    [​IMG]
     
    #15 Venice Motor Bikes, Sep 12, 2010
    Last edited: Sep 12, 2010
  16. Dan

    Dan Staff
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    This is an example of Tom's work. This thing is awesome and what ever MB I am ridding, this post gets moved to. A 600 LB rider could not bend this if (s)he rode off a cliff, cought fire and insulted alkida. Well worth making or having one made.

    A bent or lay back seat post is the best bang for the buck upgrade I know of.

    [​IMG]

    [​IMG]
     
  17. Dan

    Dan Staff
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    That looks awesome VB. (Whole MB too)
     
    #17 Dan, Sep 12, 2010
    Last edited: Sep 12, 2010
  18. tvc15

    tvc15 New Member

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    VB I'm sold... Set me up brother!
     
  19. r00t4rd3d

    r00t4rd3d New Member

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    That post does make that bike look totally different in a good way........
     
  20. culvercityclassic

    culvercityclassic Well-Known Member

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    I have to agree with you guys on the best bang for the buck for an upgrade. I felt a little tight against the bars so I decided to make one of those lay not way back seat post and try it out. I am hooked…just made two more to put on my other bikes. The one I put on my “Thrasher” bike set the seat back 3 in. which is just right.

    I attached before and after pics and also different sizes I made for my bikes. I was lucky that the seat post I used was 1/16 wall tubing. I just cut my angle needed and tig welded it together. I also made another one out of chromoly which is the bomb…..


    CCC
     

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