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  1. #1
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    How to: flip a stem

    I'd like to do this myself, but this is new to me...

    I've removed the clamp bolts, the fork and stem are free of eachother, and I have the top cup pulled up this far, but now I'm hung up. do I remove the top cap? if so, how? the fork isn't falling out....

    what next - how do I remove the stem? here's my setup....

    thanks for your assistance!
    Attached Thumbnails Attached Thumbnails How to: flip a stem-dscn2457.jpg  

  2. #2
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    The top cap should come off by unscrewing it. Usually it's just a 5mm hex bolt in the centre of the cap that you unscrew from above. In this case I don't see a bolt head. Is there a plastic cap in the centre of the top cap that you need to prise off? How did you get the cap up this far?

    Note that when reassembling you tighten the top cap as a preload before tightening the bolts on the stem itself. The aim is to get the preload torque just right so that the steerer will turn left or right without any binding, and so that there is no vertical play. Torques are important on all these bolts.
    Old La Honda in less than 20 minutes! Or you can watch race video from the low-key hill climb on Welch Creek. More at www.biketelemetry.com.

    "I think," said Christopher Robin, "that we ought to eat all our Provisions now, so that we shan't have so much to carry.", Winnie-the-Pooh, A. A. Milne.

  3. #3
    Cycling induced anoesis
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    It looks like you've somehow managed to pry the top cap up bringing the compression plug with it. You should have taken the rubber cover off the allen bolt (center of cap), then loosen/ remove the top cap.

    It's hard to tell from the pic, but I think I'd move the compression plug down the steerer tube at least 5 mm's once the stem is flipped and before reinstalling the top cap.

  4. #4
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    once I unscrewed the clamp bolts, I pulled up on the stem, which pulled the top cap up. I simply pushed the stem back down to get things as they show in the photo.

    now that I go back to it, I can easily pop out the rubber cap and the allen bolt is exposed in the center of the top cap. I'll tackle it Monday night.

    when reassembling, is the torque so important I need a torque wrench? or my LBS? or can I do it by feel? ( keeping in mind I haven't done this before )

    thanks for the assist.

  5. #5
    Cycling induced anoesis
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    Quote Originally Posted by mark4501
    once I unscrewed the clamp bolts, I pulled up on the stem, which pulled the top cap up. I simply pushed the stem back down to get things as they show in the photo.

    now that I go back to it, I can easily pop out the rubber cap and the allen bolt is exposed in the center of the top cap. I'll tackle it Monday night.

    when reassembling, is the torque so important I need a torque wrench? or my LBS? or can I do it by feel? ( keeping in mind I haven't done this before )

    thanks for the assist.
    Since you've never done this before, it's probably best to let the LBS handle reassembling. If possible, work with (or at least, watch) the mechanic so that next time you'll be familiar with the process.

    I go by feel when retightening, but YMMV.

  6. #6
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    I agree. It's not brain surgery, but you need to have confidence in your wrenching abilities for this. The consequences of any stem/steerer failure while riding are just horrible.

    If neither stem nor steerer are carbon, I'd go by feel since you can err a bit on the too tight side for the stem bolts. But if either are carbon I'd definitely use a torque wrench - my fingers just aren't calibrated enough to get it as tight as possible without going wildly beyond spec.

    Also, if you can pull the expansion plug up like that (unless you used a lot of force), the expansion plug probably needs to be looked at too.
    Old La Honda in less than 20 minutes! Or you can watch race video from the low-key hill climb on Welch Creek. More at www.biketelemetry.com.

    "I think," said Christopher Robin, "that we ought to eat all our Provisions now, so that we shan't have so much to carry.", Winnie-the-Pooh, A. A. Milne.

  7. #7
    Behind on post count
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    Quote Originally Posted by PJ352
    Since you've never done this before, it's probably best to let the LBS handle reassembling. If possible, work with (or at least, watch) the mechanic so that next time you'll be familiar with the process.

    I go by feel when retightening, but YMMV.
    +1 Your pics remind me of what I tried to do the first time I screwed around with one of those new-fangled threadless headsets. You've moved the compression plug and it needs to be moved back down. It sounds like you may not have done a lot of wrench work on your bike so definitely buy or borrow a torque wrench when you are working with the carbon parts of your bike, which is probably about any part on your Pinarello. The torque required is usually not that much and it's pretty easy to learn the touch if you have a torque wrench to compare with.

  8. #8
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    thanks for the input. I appreciate it.

    my Pinarello is no Prince so I've got a lot more aluminum than carbon bits - my frame is aluminum as are the stem, handlebars and seatpost. only the rear stays and the fork are carbon.

    I haven't looked at it yet, but I'm thinking the steerer tube is aluminum too.

    I did use force to pull the compression plug up, of course, but I wouldn't say it was a crazy amount of force. I was trying to be careful certainly. though I do have some concern about this particular part now that I've goofed with it.

  9. #9
    n00bsauce
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    Chances are reasonably good that the steerer tube is carbon fiber. Compression plugs must be used on carbon fiber steerers. They can be used on alu or steel but must be used on carbon. However, you can certainly easily tell what the steerer is made of when you remove the stem. Assuming it's carbon you should definitely use a torque wrench when re-installing the stem and use the manufacturer specs. When we say properly torque the bolts we only mean the stem and faceplate bolts, not the top cap bolt. The top cap bolt is tightened only enough to take all play out of the headset but still allow for free turning, right to left, without any binding. There is no torque setting for the top cap bolt. It's whatever it takes (and that goes by feel).

    An easy way to check for looseness in the headset is to apply the front brake while the bike is on the ground and try and rock the bike forward and backward. You will feel any looseness in the headset. If you feel looseness you have to tighten the top cap bolt a bit and check again. Keep doing this until there is no looseness. Sometimes I apply both brakes for final fine tuning to get a good feel.
    "Those who can make you believe absurdities can make you commit atrocities." Voltaire

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  10. #10
    duh...
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    look at the pic in his original post
    .


    Quote Originally Posted by mikagsd
    Fat tire Fred....you are the bike god of the universe and unless someone agrees with your reasoning they are just plain stupid

  11. #11
    n00bsauce
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    Quote Originally Posted by FatTireFred
    look at the pic in his original post
    I did and I can't tell what the steerer is made of from the small amount of steerer I can see.
    "Those who can make you believe absurdities can make you commit atrocities." Voltaire

    There are your fog people & your sun people, he said. I said I wasn't sure which kind I was. He nodded. Fog'll do that to you, he said.

    "We are all ignorant about most things."
    Mel Erickson

  12. #12
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    it's done!

    when I got home from work this evening, I took the stem off, flipped it, put things back together enough to give it a 1 block test ride. didn't even take me 10 minutes. was pretty easy to do once I learned the little rubber thingy that covers up the 5mm allen bolt comes right out and reveals the allen bolt!

    anyway, flipping the stem seems to provide some improvement that I was looking for. so I put the bike in my vehicle and took it to my LBS for the Pro to tighten things up properly. he even did it for me no charge. btw, the steerer is carbon.

    thanks to eveyone for your input. I learned some things and got advice needed to point me in the right direction...in this case my LBS.

  13. #13
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    Basically that top cap is compressing everything together. So, the tighter you make it, the more friction will be present in the bearings and such. A good example of this is to tighten to top cap quite a bit. Then lift up the front of the bike by your top tube. You will see that the handlebars don't fall to one side quite as easily and might even get stuck in place. A well tightened top cap will keep everything together yet still let everything move freely.
    “The best rides are the ones where you bite off much more than you can chew–and live through it.”–Doug Bradbury

  14. #14
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    how much better is the ride/feel? I'm thinking about doing the same thing with my 07 Lemond Zurich.

  15. #15
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    haven't really ridden it yet - just up and down the block once.. by the time I get home at night it's pitch dark. weather permitting ( i.e, no rain ) , I'll get out on it a couple times this weekend.

  16. #16
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    You back yet?

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