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  1. #1
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    Coil Shock Fitment on HD4: Can someone explain?

    I know that Ibis says it won't work due the clevis yoke extending the eye to eye too far for proper bushing overlap but, what does that mean exactly? Can someone elaborate on that?

  2. #2
    Ride Fast Take Chances :)
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    It has a lot more to do with the suspension leverage ratio. It's not progressive enough to prevent a coil from bottoming out with proper sag. If you get a progressive spring it can work.
    The leverage curve fills the holes in an air spring and was designed with air in mind. The Fox X2 is an excellent shock and gives performance extraordinarily close to coil with a weight advantage.
    Making shit harder than it needs to be isn't awesome, it's just...harder.

  3. #3
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    Quote Originally Posted by alexbn921 View Post
    It has a lot more to do with the suspension leverage ratio. It's not progressive enough to prevent a coil from bottoming out with proper sag. If you get a progressive spring it can work.
    The leverage curve fills the holes in an air spring and was designed with air in mind. The Fox X2 is an excellent shock and gives performance extraordinarily close to coil with a weight advantage.
    The leverage ratio makes sense but what does that have to do with bushing overlap? LOL Ibis' way of going the extra mile to try and keep people from trying it?

    MTBs need dual rate spring setups like they use in the off road world.

  4. #4
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    From another thread, Noah works for MRP.

    Quote Originally Posted by romulin View Post
    I am hoping to get some more information on the progressive springs and whether I can put this onto hd4. They have been saying something about clevis extending a yoke or something, which I don't understand but I know that specialized enduros like breaking coils so don't want this to happen to me.
    Now, Noah may enter...
    Here's my response in another thread that's relevant:

    Bikes that use a layout whereby the rear shock eyelet is turned 90 and a yoke is utilized present some challenges to shocks in general, and especially coil shocks. They effectively lengthen the shock and increase the stress on them and potential for side loading.

    Among coil shocks, the Raze and Hazzard have pretty large shafts, and the eyelet-to-shaft connection (the weak spot for coil shocks) has been beefed up in the Hazzard compared to the (v1) Raze to better deal with these stresses. However, we can't guarantee that "yoked" bikes won't damage or break the shocks and if that occurred it wouldn't be covered under warranty. Additionally, this type of failure could result in damage to the frame which the frame manufacturer might decline to cover under their warranty.

    All that said, I've put hundreds of heavy miles on a Hazzard on my Pivot Firebird and had no issues. But that experience alone isn't enough for us to approve them without caveats on every or even any bike with that type of linkage.

  5. #5
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    Quote Originally Posted by bdundee View Post
    From another thread, Noah works for MRP.

    Quote Originally Posted by romulin View Post
    I am hoping to get some more information on the progressive springs and whether I can put this onto hd4. They have been saying something about clevis extending a yoke or something, which I don't understand but I know that specialized enduros like breaking coils so don't want this to happen to me.
    Now, Noah may enter...
    Here's my response in another thread that's relevant:

    Bikes that use a layout whereby the rear shock eyelet is turned 90 and a yoke is utilized present some challenges to shocks in general, and especially coil shocks. They effectively lengthen the shock and increase the stress on them and potential for side loading.

    Among coil shocks, the Raze and Hazzard have pretty large shafts, and the eyelet-to-shaft connection (the weak spot for coil shocks) has been beefed up in the Hazzard compared to the (v1) Raze to better deal with these stresses. However, we can't guarantee that "yoked" bikes won't damage or break the shocks and if that occurred it wouldn't be covered under warranty. Additionally, this type of failure could result in damage to the frame which the frame manufacturer might decline to cover under their warranty.

    All that said, I've put hundreds of heavy miles on a Hazzard on my Pivot Firebird and had no issues. But that experience alone isn't enough for us to approve them without caveats on every or even any bike with that type of linkage.
    Good info. Thank you for sharing.

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