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  1. #1
    Senior Member Thumpic's Avatar
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    Treading the thin line of stem safety.........

    I am trying to get a more comfortable position on my bike. I think it is the correct size as the stand over leaves about an inch between the top tube and the honeymoon hardware. But I have a generous gut (not as bad as my avatar) and would like to sit more upright.

    I understand the mechanics of how the stem works with the wedging action between the anchor nut; the bottom of the stem and the fork tube. It appears that I can raise the stem another inch (easily) past the safety line and still maintain the mechanical integrity of the stem/fork tube attachment. Is there some other factor to consider?? All the parts are clean and lubed so I am sure of a firm assembly between the two components.

    Thanks for your help!!!

    btw....'85 Panasonic DX3000...............
    Thumpic....

    Green is the new "CHEAP"

  2. #2
    Senior Member CACycling's Avatar
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    I wouldn't do it. The "minimum insertion" line is there for a reason. Either get a longer stem or a stem extension.

  3. #3
    rebmeM roineS JanMM's Avatar
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    Worst case scenario: Your estate will have a hard time winning a judgment against the stem manufacturer if you raise it 1" above the line.
    Search for a longer stem.

  4. #4
    Senior Member
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    Bike shops in my area usually have a supply of used threaded stems of various sizes that they will trade at a modest fee.

    Al

  5. #5
    hello roadfix's Avatar
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    Nitto Technomic

  6. #6
    Senior Member Retro Grouch's Avatar
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    Quote Originally Posted by roadfix View Post
    Nitto Technomic
    My answer too. Do it right the first time.

  7. #7
    Senior Member DieselDan's Avatar
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    Your stem may appear to be seated securely inside the steerer tube 1" about minimum insertion, but the wedge is pushing against the weaker, threaded section of the steerer tube.
    Bikes use brakes to stop.

    If your bike has breaks, don't ride it.

  8. #8
    Senior Member
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    Quote Originally Posted by DieselDan View Post
    Your stem may appear to be seated securely inside the steerer tube 1" about minimum insertion, but the wedge is pushing against the weaker, threaded section of the steerer tube.
    That's absolutely correct and a recipe for catastrophic failure. Either get the Nitto Technomic stem recommended above or Profile Design's H2O, an up-angled stem that also has a long quill.

  9. #9
    surly old man jgedwa's Avatar
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    Yup. It seems like you can go higher. But the threaded portion of the stem is significantly weaker than the lower portion. When it goes, it goes catastrophically. A cheapo new or used stem at the LBS is a much better deal than dentures.

    jim

    p.s., I a hack at heart so its not just a knee-jerk reaction to advise against it. Plus, if you are big and strong, you really need to have trustworthy bars and stem.
    Cross Check Nexus7, IRO Mark V, Trek 620 Nexus7, Karate Monkey half fat, IRO Model 19 fixed, Amp Research B3, Surly 1x1 half fat fixed, and more...
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    SB forever

  10. #10
    Your mom
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    You need a Nitto Technomic, probably the deluxe, if you're not planning on raising the bars a lot.

  11. #11
    Perineal Pressurized dobber's Avatar
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    Oh the heck with all the worry warts here. That line is there only because lawyers made them put it there.



    Besides, they can do incredible things these days with dental surgery.
    This is Africa, 1943. War spits out its violence overhead and the sandy graveyard swallows it up. Her name is King Nine, B-25, medium bomber, Twelfth Air Force. On a hot, still morning she took off from Tunisia to bomb the southern tip of Italy. An errant piece of flak tore a hole in a wing tank and, like a wounded bird, this is where she landed, not to return on this day, or any other day.

  12. #12
    Senior Member Thumpic's Avatar
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    thanks.............finally somebody said that "nitto technomic" was a stem..........I didn't know what the hell you first guys were talking about until then.......I'll get a new taller stem................Thanks for the advice...........
    Thumpic....

    Green is the new "CHEAP"

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