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  1. #1
    Unobtanium-Based Lifeform calamarichris's Avatar
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    Moving Seat Forward on a [Very] Laidback Dutch Bike

    Q: Would you deem it foolhardy/reckless to buy THIS setback SEATPOST and install it backward to shift the seat forward? If so, is there a more prudent way to shift my seat forward at least 1.5cm? (2.0cm would actually be better.)

    I adore this neat old Dutch bike with old Look pedals (PS76) and a 25.4mm seatpost, but pedaling this heavy sucker up the hills with the present rearward position on my commute is destroying my knees! (Despite keeping my cadence around 80.)

    I'd prefer to keep the Brooks saddle, but will gladly ditch it if there is a seat/seatpost combination that will permit me to keep both bike and knees. Mille grazzi!



    P.S. The shoes are Dromartis, and they're another reason I really want to continue riding this bike.

  2. #2
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    It won't work.

    Get a seatpot designed triathletes. Like the Fast Forward by Profile Design. Nitto makes one too, the S66.

  3. #3
    Unobtanium-Based Lifeform calamarichris's Avatar
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    Thanks, but do they make them in a 25.4mm diameter?

    Most modern seatposts seem to be 27.2 or 31.6.

  4. #4
    Asi
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    why not inverting the original seat post?

  5. #5
    Unobtanium-Based Lifeform calamarichris's Avatar
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    Quote Originally Posted by Asi View Post
    why not inverting the original seat post?
    It's a Thomson, which would bring it forward 0.0 cm.
    The original seatpost (in the top photo) was a very rusty steel post (also with no adjustment), and the original seat was very rusty with a broken spring.
    Thanks though.

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    The best I can think of is a straight post like this http://www.wallbike.com/seatposts/kalloy200.html Kalloy SP-200, comes in 25.4

    Use the clamp sandwich like this ... http://www.wallbike.com/clampvssand.html .... turn the sandwich part around, as the angle is adjustable to infinity.

    Brooks make sandwiches.... probably others too. Google "Brooks saddle clamp"

    There you go
    Last edited by Garthr; 06-23-10 at 06:06 PM.

  7. #7
    headtube. zzyzx_xyzzy's Avatar
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    Layback posts for BMX come in 25.4. Most of then take a standard 7/8" saddle clamp as found on many old seat posts so you can definitely flip them around.

    http://www.google.com/products?q=25.4+layback+seat+post

  8. #8
    Unobtanium-Based Lifeform calamarichris's Avatar
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    Quote Originally Posted by Garthr View Post
    The best I can think of is a straight post like this http://www.wallbike.com/seatposts/kalloy200.html Kalloy SP-200, comes in 25.4

    Use the clamp sandwich like this ... There you go
    It appears those sandwich clamps are for the dual-railed Brooks saddles, yes?
    Unfortunately my B67 is a single rail saddle and I don't believe it's usable with those sandwich thingies, (or with the BMX layback posts, ZZyZx, unless there's some kind of adapter clamp.)

  9. #9
    coprolite fietsbob's Avatar
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    I assume you have tried putting the saddle clip ahead of the seatpost already..

    I got a 25,4/1" seat post from SBS/Redline, Its of Chro-Moly steel tube so will be stronger, useful with a long extension above the frame.

    From Brompton dealers, get a saddle adapter pin, it mounts on the 7/8" top part of basic seatposts, and has a horizontal 7/8" tube welded onto its clamp .

    see: http://www.sjscycles.co.uk/product-B...QSAPA-2926.htm
    Then the saddle clip would have the saddle rails above the bolt that clamps it to this pin . It can rotate side to side , Just get the seat clip tight .

    I suppose you can use the twin or single rail seat clip with that , still , it will be horizontal on the SAP, some adjustment forward on the SAP 's length..

    for single rail saddle there is a Brompton made Penta clip, which is mostly aluminum, it is stepless and so can be set at any angle.

    see: http://www.sjscycles.co.uk/product-B...LIPA-13716.htm

    There is a dealer network for Brompton In the US, SJS links used for illustration.
    Last edited by fietsbob; 06-24-10 at 12:54 PM.

  10. #10
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    Quote Originally Posted by calamarichris View Post
    If so, is there a more prudent way to shift my seat forward at least 1.5cm? (2.0cm would actually be better.)
    I don't understand why people are saying your proposed solution won't work.

    I accidentally assembled a bike with the seatpost oriented backwards. I kept thinking how cramped I felt, and the bike was too small for me. I was planning to buy a Truvativ laidback seatpost to get a little more rearward adjustment. Then, one day I realized I had the seatpost backwards. Spun it around, and it was like having an immediate 1" to 1.5" of rearward adjustment.

    Without understanding why people are saying it shouldn't work, I'd do exactly what you proposed. But, I'd save money with the M-Wave seatpost for $8. That has the standard 30mm offset. If your current post is zero offset, spinning this forward ought to give you at least the 1/2" you're looking for.

  11. #11
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    Quote Originally Posted by calamarichris View Post
    It appears those sandwich clamps are for the dual-railed Brooks saddles, yes?
    Unfortunately my B67 is a single rail saddle and I don't believe it's usable with those sandwich thingies, (or with the BMX layback posts, ZZyZx, unless there's some kind of adapter clamp.)
    Saddle clamps come in single and double rail.


    Quote Originally Posted by az2008 View Post
    I don't understand why people are saying your proposed solution won't work.

    M-Wave seatpost for $8. That has the standard 30mm offset. If your current post is zero offset, spinning this forward ought to give you at least the 1/2" you're looking for.
    I've never seen a seatpost that it would work. Seatposts are not designed to be used either way. The angle of the seat will be way up. This is with Campy, Shimano,Kalloy, SR and a host of other seatposts. But, don't listen to me, try it yourself and see.

  12. #12
    AEO
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    I don't quite understand how being far back on the saddle is wrecking your knees.

    I mean, the ultimate form of waaaaay back on the saddle is a recumbent.
    Food for thought: if you aren't dead by 2050, you and your entire family will be within a few years from starvation. Now that is a cruel gift to leave for your offspring. ;)
    http://sanfrancisco.ibtimes.com/arti...ger-photos.htm

  13. #13
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    Quote Originally Posted by AEO View Post
    I don't quite understand how being far back on the saddle is wrecking your knees.

    I mean, the ultimate form of waaaaay back on the saddle is a recumbent.
    I'd agree with that ...... wrecking of the knees is often the seat being set too low or high, or loading the pedal too soon in the pedal stroke. The latter will surely wreck your knees no matter where the saddle is!

    Of course ... what is meant by "wrecking of the knees"? Many people call common kneecap pain , pain in the knee. It's really not the knee at all, as it has nothing to do with the joint itself.

  14. #14
    AEO
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    too low causes knee injury and too high causes hip injury

    if you haven't already, check out http://www.cptips.com/knee.htm
    give your legs a massage before and after a ride, especially on your quad and Iliotibial band region around the knee.
    Food for thought: if you aren't dead by 2050, you and your entire family will be within a few years from starvation. Now that is a cruel gift to leave for your offspring. ;)
    http://sanfrancisco.ibtimes.com/arti...ger-photos.htm

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