1. The most important thing about buying a new bike is to make sure it fits. The only way you'll know if the bike is right for you is to size up the bike and make sure that the bike's geometry matches your body's geometry. Ask questions and do some research.
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2. If possible, try to find a shop that will let you demo the bike on real dirt. Five minutes in a parking lot won't cut it. You wouldn't buy a car without a real world test drive, and a bike should be no different.
3. Don't belive the hype. Just because your favorite rider or best friend rides a certain bike, that doesn't mean that's the best one for you. Have an open mind and be realistic about your needs and ability.
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  1. #1
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    Smile seat clamp tightness

    Hi to all. My seatpost is slipping and just want to know what is the correct or proper tightness of the seat clamp im using the bolt on type. Im afraid might over tighten it up and damage seat tube. Any tips how you tighten yours, thanks in advance.

  2. #2
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    Reputation: Bikinfoolferlife's Avatar
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    It doesn't take a lot of torque if everything fits properly; somewhat dependent on the size bolt. Too tight and you're likely to bend the bolt let alone damage the frame or seatpost.
    Here's Park's torque page for their take on tightening bolts and such and some suggested values http://www.parktool.com/repair/readhowto.asp?id=54.

    You don't provide details of what post in what frame with what collar/clamp bolt (materials vary), or what you're doing (greasing the post or not, what torque you're tightening the bolt to, etc.), so hard to tell what your problem might be if you are tightening the bolt sufficiently. Have you checked to make sure you have the proper size post for your seat tube? How does the post fit in the seat tube before tightening the clamp bolt? Loose? Tight?
    "...the people get the government they deserve..."
    suum quique

  3. #3
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    My frame is hardtail Trek 6700. My seatpost is the exact size Im using thomson seatpost and hope 36.4 seat clamp bolt on. I did clean the inside of the seat tube and put small amount of grease but I guess I did not tighten up properly the seat clamp bolt thats why my seatpost slips. Do I need to tighten the bolt of the clamp all the way in until the bolt head stop rotating? How tight? The bolt of hope seat clamp is quite small Im worried I might over tighten it and damage the seat post and seat tube. I just started riding late last year and still got a lot to learn.. cheers.

  4. #4
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    Reputation: Maida7's Avatar
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    I think the bolt will break before you damage anything. Tighten it as much as it takes to keep things from moving. As long as you dont break the bolt your probably OK. But sometimes seat posts and seat tubes aren't quite the right size for each other. In your case it may be a bit of a loose fit. If you can't fix it by just tightening the bolt you can shim it to make it fit tighter with a piece of an alumium soda can.

  5. #5
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    I have a trek 4500, and I eventually had to tighten the bolt about 3/4 of a turn past the point where I can open the clamp with my hand. That isn't a terribly helpful description I know, but I found it must be TIGHT. Get some hex keys with long handles, torque is your friend.

    I might also try the shim trick, but so far, so good.

  6. #6
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    Thanks guys, my seatpost is the exact size but there is a bit small slack in between the seat tube and seatpost if my seat clamp is not yet tighten the seatpost goes down all the way inside the seat tube I will try to put soda can shim first and tighten it up and update you the result. I will test and see any progress.

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