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  1. #1
    meow bostongarden's Avatar
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    Can't adjust profile fast forward clamps so seat is flat, help :-)

    For the life of me, I cannot adjust the clamps tightly so that the nose on the seat is anything other than pointing down!!! This strikes me as weird, but, maybe there is something inherent in the Profile Fast Forward seatpost which makes this normal.

    It is an older 27.0 profile design fast forward seatpost with a front and back bolt. My seat is a circa 1991 Avocet Racing I (I don't think this should matter, but, just in case I'm letting you know. Also, the rails are fine).

    I have the back bolt as tight as possible; I then tighten the front bolt so that the clamps come together well enough to keep the seat stable. But, when I do this, it forces the nose down, which, when I ride, forces me to slide down to the nose!! In order to stay in the proper place in the saddle, I have to use my arms to hold myself in place.

    Is this normal for this type of seatpost? I know that they are designed for TT, but, it strikes me as bizarre that I cannot adjust the "level" to the way I want it with the clamps tight.

    I don't think this is rocket science; although, this is the first time I have had a double bolt seatpost. Am I missing something here?

    I appreciate your help!! Happy to provide information as desired.

  2. #2
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    If the rear bolt is screwed all the way in it will force the nose of the saddle down. Two-bolt seatposts use the two bolts in opposition to set the seat angle so you have to loosen the rear bolt and tighten the front to raise the saddle nose.

  3. #3
    meow bostongarden's Avatar
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    Thanks, I'll give it a go!!!!

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    Whoops, I just reread what I recommended and it's incorrect. The rear bolt should pull the back of the seat down and the nose up so if you loosen the front bolt and tighten the rear bolt all the way, that should leave the seat pointed up, not down. Is the rear bolt the stock one and has it got enough threads to pull the seat up far enough? If it's bottoming out on the threads, perhaps a better bolt will help.

    BTW, how are you orienting the seatpost? Is the bend going forward as intended for Tri use?

  5. #5
    meow bostongarden's Avatar
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    Quote Originally Posted by HillRider View Post
    Whoops, I just reread what I recommended and it's incorrect. The rear bolt should pull the back of the seat down and the nose up so if you loosen the front bolt and tighten the rear bolt all the way, that should leave the seat pointed up, not down. Is the rear bolt the stock one and has it got enough threads to pull the seat up far enough? If it's bottoming out on the threads, perhaps a better bolt will help.

    BTW, how are you orienting the seatpost? Is the bend going forward as intended for Tri use?
    Nevertheless, I tried what you said because my method was not working. Indeed, tightening up the front bolt a bit first, or, doing each bolt, front and back, a little bit each alternatively, did not yield the desired result.

    I believe that I have tightened the back bolt as much as possible and that a longer bolt would not enable me to "pull it back" any farther.

    The seatpost is supposed to be oriented with the bend forward and this is how I am setting it up.

    In spirit, the back bolt is ok at the fully tightened position and the seat is level as desired; the problem is that the clamp is not tight enough against the rails to keep it stable, so, I have to tighten the front bolt a bit more to make the rails clamped properly; but, when I do this, the nose goes down too much.

    Something is unusual or amiss here. Not sure what the fix is, assuming that there is one for my case.

    I appreciate your help!!

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    One other thing occured to me, what type of frame is this seatpost installed on? It's intended to make a road frame with a 72° or 73° seat tube angle behave like a tri-specific frame with a 78° seat tube angle. Any chance you already have a tri frame with the steep sear tube angle and the Profile seat post is too much of a good thing?

  7. #7
    meow bostongarden's Avatar
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    Quote Originally Posted by HillRider View Post
    One other thing occured to me, what type of frame is this seatpost installed on? It's intended to make a road frame with a 72° or 73° seat tube angle behave like a tri-specific frame with a 78° seat tube angle. Any chance you already have a tri frame with the steep sear tube angle and the Profile seat post is too much of a good thing?
    Thanks for thinking about this!!! I put it on a 1992 Bridgestone RB-1, 53cm with seat angle of 73.5 degrees. This is crazy!!

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    A picture is worth a thousand words, can you post one?
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  9. #9
    The Site Administrator: Currently at home recovering from a couple of strokes,please contact my assistnt admins for forum issues Tom Stormcrowe's Avatar
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    I suspect it's because the saddle is oriented for use primarily for use with aerobars, since it's a TT/Tri specific seatpost.
    on light duty due to illness; please contact my assistants for forum issues. They are Siu Blue Wind, or CbadRider or the other 3 star folk. I am currently at home recovering from a couple of strokes. I am making good progress, happily.


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  10. #10
    meow bostongarden's Avatar
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    Quote Originally Posted by dperreno View Post
    A picture is worth a thousand words, can you post one?
    I'll look to post some pictures that can detail the situation more...

  11. #11
    meow bostongarden's Avatar
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    Quote Originally Posted by Tom Stormcrowe View Post
    I suspect it's because the saddle is oriented for use primarily for use with aerobars, since it's a TT/Tri specific seatpost.
    I had wondered about this too...I do not do TT or ride on aero-bars...but, is a nose slightly down a typical TT position? Also, you gotta admit, isn't it still weird that a seatpost would not allow for at least a "level" setup? Thank you for your thoughts on this mystery!!!

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    One more comment, you don't need a longer rear bolt but you may need a shorter one.

  13. #13
    meow bostongarden's Avatar
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    Quote Originally Posted by HillRider View Post
    One more comment, you don't need a longer rear bolt but you may need a shorter one.
    Much appreciated!! I'll have to think about this one because, again, with the current back bolt, the current clamp mechanism is in full/closest contact with the back part of the seatpost in the "best" setup that I can get at present. I'm not sure of the effect of a shorter bolt.

    As a related aside; I put out a post to TT riders on the Road Cycling forum and asked about nose position and no one indicated that the proper position should be down or anything other than level.

    I'll continue to work on this and report back when I find out what's up with this seatpost!!!

    Many thanks again.

  14. #14
    Small Member maddmaxx's Avatar
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    2 thoughts


    1. Although it may appear symetrical, you might try to reverse the saddle mechanism (unbolt rear and front, reverse and rebolt) to see if that helps.

    2. While reading the installation instructions (Profile Design website tech/docs) the adjustment proceedure calls for the saddle to be slightly nose down.

  15. #15
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    Quote Originally Posted by maddmaxx View Post
    1. Although it may appear symetrical, you might try to reverse the saddle mechanism (unbolt rear and front, reverse and rebolt) to see if that helps.
    +1
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  16. #16
    meow bostongarden's Avatar
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    Quote Originally Posted by maddmaxx View Post
    2 thoughts

    1. Although it may appear symetrical, you might try to reverse the saddle mechanism (unbolt rear and front, reverse and rebolt) to see if that helps.

    2. While reading the installation instructions (Profile Design website tech/docs) the adjustment proceedure calls for the saddle to be slightly nose down.
    Thanks:
    1) I did try reversing the clamps...same results.
    2) Ah, nice, did not know this was out there...found it here...these instructions do say "Adjust the saddle height and alignment and tighten binder bolt to a torque recommended by the frame / clamp manufacturer. Align the saddle angle. Using the M5 wrench, tighten the bolts (#4) to adjust the saddle angle until this angle is slightly “nose down” from the normal required position. Then using your 5mm Allen wrench, tighten the M6x30 socket cap bolts (#4) to a torque of 63in-lb. (7.2Nm)."

    But, the thing is that "bolt #4" is the rear bolt, which when tightened, pulls the nose up. My interpretation of this is that the second part of this process, that is "Then using your 5mm Allen wrench, tighten the M6x30 socket cap bolts (#4) to a torque of 63in-lb. (7.2Nm)," would pull the nose up to the "normal required" position. In addition, it just says that nose should be down from "normal required" position, it does not say what is a "normal required" position.

    I also did the following this morning:

    1) Took it to my friends at Bicycle Sport Shop -- unable to get nose anything other than down.
    2) Took it to my friends at a nearby Performance bike shop -- unable to get nose anything other than down; also tried seatpost with a modern/current saddle with same undesirable results.
    3) Posted to the folks in the Road section of this forum asking about TT positions...no one said that the nose should be down.

    I am now convinced that something is wrong with the design or with the seatpost itself. Thanks for your help. I'll report back after I speak with Profile-Design about this. Sheesh, I just wanna ride!!!!

  17. #17
    Senior Member BCRider's Avatar
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    You'll want to check to see if the upper clamp shoe is actually being limited in travel by the lower stem assembly's bolt ears. If you have tightened the rear bolt as much as you can and that has rotated the clamping shoe so it's in contact then that's as far as you'll get without breaking out a metal file and removing some metal.

    Try to get that picture and make it a series of closeups from different angles so we can see this issue as much as possible.

    Looking at the pictures of this post it really does appear to be a serious tri bike setup what with the angle in the post for the serious saddle positioning. I'm having trouble figuring out if it's sopposed to angle back or forward but either way it's pretty extreme.

    Mind you so is the riding position in tri bikes. With the body leaned that far forward I'd suspect that most riders would WANT at least a small nose down amount to keep the sitting pressure located on the sit bones. But that same post used for a more casual riding position could easily result in the rider sliding forward and hating it. I gather this is your situation? If so then perhaps this isn't the seat post you should be using?
    Model airplanes are cool too!.....

  18. #18
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    Quote Originally Posted by BCRider View Post
    Looking at the pictures of this post it really does appear to be a serious tri bike setup what with the angle in the post for the serious saddle positioning. I'm having trouble figuring out if it's sopposed to angle back or forward but either way it's pretty extreme.
    It's supposed to angle forward. It's supposed to position the rider further forward and the intent is to make a normal road frame with a 72 or 73° seattube angle behave as if it had a ~78° seat tube like a dedicated tri-bike. Why the OP is having the problems he is is still a mystery that perhaps Profile Design can finally solve

    I suppose someone with a need for a HUGE amount of set back could use it angled the other way on a regular road frame.

  19. #19
    meow bostongarden's Avatar
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    I emailed Profile-Design Customer Service about my situation and here is an excerpt from their reply: "... the fast forward post was designed around a 73 degree seat tube angle. Your seat tube angle could be steeper. You might need to switch to another seat post if you cannot get it to the desired angle. Unfortunately I do not have a good answer for you..."

    It strikes me as shocking were this seatpost designed such that the saddle could not get level on a bike with a seat angle greater than 73 degrees. Hey, if that's the case, fine...but, strikes me as poor design and very very strange. In addition, Profile-Design's literature indicates that one can effectively change a 73 degree angle to a 78 degree angle. It does not say that any bike with a seat angle greater than 73 degrees -- mine has 73.5 degree seat angle -- would not be able to get the saddle level.

    I'll keep exploring this because now I am curious as to whether the seatpost was designed such that a bike with a seat angle greater than 73 degrees would not allow for a level saddle.

  20. #20
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    A 0.5° angle difference shouldn't be enough to make the post unusable.

  21. #21
    meow bostongarden's Avatar
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    Agreed!! Naturally, I am searching for a good solution. But, now that I ran into this oddity, I am intellectually curious about this situation.

  22. #22
    meow bostongarden's Avatar
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    I spoke with some folks at BikeSport Michigan and at Koobi because I respect their opinions...they did not say anything that would suggest that the design of the seatpost should force me to have the saddle nose down...however, a fellow at Koobi did come up with a new possible explanation for my situation, which I won't be able to check out for a few weeks...maybe, maybe, the seat angle on my road bike is not as specified by the manufacturer catalog (courtesy of Sheldon Brown)...I'm gonna check this out...beyond this, I am at a loss to understand why the seatpost is not working for me...I'll keep digging (and I'm posting here for my own archiving as well -- sorry about that).

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