head tube angle vs fork stanchion angle- Mtbr.com
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  1. #1
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    head tube angle vs fork stanchion angle

    quick question -

    Why is the angle of the fork stanchions always a degree or two steeper than that of the head tube?

    On some bikes the difference is less obvious than on others, but it's always there - I went ahead and exaggerated it a bit in my drawing below just to make it clear what I'm talking about-

    head tube angle vs fork stanchion angle-fork6.jpgThanks-

  2. #2
    Fat-tired Roadie
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    I didn't think it was! Sure it's not an optical illusion? Bear in mind that, especially recently, a lot of head tube shapes get wider from top to bottom.
    "Don't buy upgrades; ride up grades." -Eddy Merckx

  3. #3
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    They're not, that's an optical illusion.

    Here is an example drawing from RockShox showing the steerer axis parallel to the stanchions and lowers. It's the dashed line through the steerer in the profile view that continues down to the 46mm offset dimension at the bottom

  4. #4
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    The only reason the steerer axis might not run parallel is if the fork was in a bad crash and the lowers were tweaked.
    You cannot go against nature, because when you do, its part of nature too.

  5. #5
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    What you're seeing is probably a little bit of barrel distortion from the camera lens. Same reason the center of the frame appears to be slightly closer to the lens than the wheels

  6. #6
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    Quote Originally Posted by next View Post
    quick question -

    Why is the angle of the fork stanchions always a degree or two steeper than that of the head tube?

    On some bikes the difference is less obvious than on others, but it's always there - I went ahead and exaggerated it a bit in my drawing below just to make it clear what I'm talking about-
    That's an optical illusion man. I fell for it as well a few years ago...
    Last edited by Max24; 03-02-2015 at 07:03 PM.

  7. #7
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    Yep per , there is HT angle and fork offset , but the stanchions and the steer tube are on the same angle as the HT, its like was said above ----------an optical illusion .

    I will say the green bike in the OP first pic does look like the fork is bent from the angle the pic was shot at .

    Or you loaned the bike out and your buddy slammed a parked car

  8. #8
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    Forks are actually straight?! I saw that diagram of the RockShox fork, and it blew my mind.

    Here are just a couple more pictures of bikes with forks that look seriously off/not straight to me. Maybe it's barrel distortion, or an optical illusion, or I just need to visit my optometrist. The 2nd bike is actually my wife's Wally-world bike, right before I sold it.

    Anyway- I'm moving on with my life. But I'm not happy about it.

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  9. #9
    transmitter~receiver
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    Even if it were the case, which it isn't, why would it matter?

    It is definitely true of many rigid forks.
    Quote Originally Posted by pvd
    Time to stop believing the hype and start doing some science.
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  10. #10
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    i like forks to be straight with the head tube, or if the head tube has too much angle, i like the forks to have the back angle like these photos, basically i hate it when forks
    lean outwards because it looks bad and feels bad and feels like they could snap.

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