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  1. #1
    Nim
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    New question here. Is it possible? X post

    Is there a way to make a full suspension bike rideable (get you back to the car), when the deraileur snaps and all you can do is try to make the bike into a SS. It seems that the rear suspension travel causes chain issues which prohibits pedalling. Maybe a SS specialist has a suggestion.

  2. #2
    Nouveau Retrogrouch SuperModerator
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    Can you lock out the shock?
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  3. #3
    Nim
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    Nope

    Quote Originally Posted by shiggy
    Can you lock out the shock?
    I have Fox DHX - no lockout. I could crank the pro pedal to its max, maybe add air to the booster valve??? Preload is at max setting. But I'd guess I still get some travel.

  4. #4
    Nat
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    Quote Originally Posted by Nim
    Is there a way to make a full suspension bike rideable (get you back to the car), when the deraileur snaps and all you can do is try to make the bike into a SS. It seems that the rear suspension travel causes chain issues which prohibits pedalling. Maybe a SS specialist has a suggestion.
    I've tried this before with a FS bike that got a broken derailleur. This bike was an old high-pivot swingarm design on which the chain length was at its shortest at suspension full extension. I went ahead and turned it into a singlespeed using the small ring and big cog, and the chain kind of held the swingarm at full extension. When I'd hit a bump, the swingarm would want to move but the chain wouldn't let it. It kind of worked, kind of didn't, but I was able to pedal (slowly) for a few miles.

  5. #5
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    Hose clamps???

    Carry a worm gear hose clamp or two. Put the hose clamp around the part of the shock that moves in and out (the shaft) and up against the housing. Then clamp it down real hard. Use 2 to make sure you've got good clamping. With this you will cause the shaft not to be able to move into the housing rendering you with a locked out shock. Now, the problem might become that you have put nicks and cuts onto your shaft doing this. But, you probably will have gotten home.

    I"ve never tried this. I have heard folks say this is a way to deal with a front fork that has dumped its air and now has collapsed.

    Regards,
    Marc
    LA

    Quote Originally Posted by Nat
    I've tried this before with a FS bike that got a broken derailleur. This bike was an old high-pivot swingarm design on which the chain length was at its shortest at suspension full extension. I went ahead and turned it into a singlespeed using the small ring and big cog, and the chain kind of held the swingarm at full extension. When I'd hit a bump, the swingarm would want to move but the chain wouldn't let it. It kind of worked, kind of didn't, but I was able to pedal (slowly) for a few miles.

  6. #6
    Nouveau Retrogrouch SuperModerator
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    Yikes! I would rather walk than risk damaging the shock like that.
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  7. #7
    dirty hippy mountainbiker
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    I think he meant like when you're using a FS bike to get around a post-apocolyptic wasteland and you're being chased by flesh eating zombies and have to get away, but your derailer gets ripped off. In that situation I think I'd be pretty ok with loosing travel and ruining a shock or fork.
    Mike Henderson, Dirty Hippy Mountain Biker and part owner of Jet Lites.

  8. #8
    Nat
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    Quote Originally Posted by LocoMotoMan
    Carry a worm gear hose clamp or two. Put the hose clamp around the part of the shock that moves in and out (the shaft) and up against the housing. Then clamp it down real hard. Use 2 to make sure you've got good clamping. With this you will cause the shaft not to be able to move into the housing rendering you with a locked out shock. Now, the problem might become that you have put nicks and cuts onto your shaft doing this. But, you probably will have gotten home.

    I"ve never tried this. I have heard folks say this is a way to deal with a front fork that has dumped its air and now has collapsed.

    Regards,
    Marc
    LA
    I read that article in the bike mag also, circa 1992. Immediately I thought to myself, "What a TERRIBLE idea. Destroy the stanchion tube with a hose clamp (that's probably going to slip anyway) rather than just ride home with the fork bottomed out."

  9. #9
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    What the heck, remove the shock and replace it with a fixed shaft with an eyelet at each end. If you're really prepared for this, the shaft will be the right length for a magic gear on a chosen cog.

  10. #10
    Nouveau Retrogrouch SuperModerator
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    Quote Originally Posted by pacman
    What the heck, remove the shock and replace it with a fixed shaft with an eyelet at each end. If you're really prepared for this, the shaft will be the right length for a magic gear on a chosen cog.
    or have a shaft with threaded eyelets so you can adjust the chain tension.
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  11. #11
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    Quote Originally Posted by shiggy
    or have a shaft with threaded eyelets so you can adjust the chain tension.
    And of course one eyelet would be left hand threaded so you can just put the shaft in and turn the center section to adjust chain tension without having to remove the shaft.

  12. #12
    Nouveau Retrogrouch SuperModerator
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    Quote Originally Posted by Kennetht638
    And of course one eyelet would be left hand threaded so you can just put the shaft in and turn the center section to adjust chain tension without having to remove the shaft.
    and that is called a turnbuckle!
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  13. #13
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    Depending on the suspension design you might survive, some 4-bars change chain length very little but shorten the effective chainstay when the suspension compresses (my FSR is this way) so I guess on my FSR I could find a combo that's close with the suspension slightly compressed then just air up the shock to tension the chain. Lee rode the bottom 5 miles or so of Mckenzie River on his FS Jamis without a rear Deraileur and survived.

  14. #14
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    Wrap your shaft..shock shaft that is..with inner tube...

    Quote Originally Posted by Nat
    I read that article in the bike mag also, circa 1992. Immediately I thought to myself, "What a TERRIBLE idea. Destroy the stanchion tube with a hose clamp (that's probably going to slip anyway) rather than just ride home with the fork bottomed out."
    You could wrap your shock shaft with something tha twon't mar it when you tighten up the hose clamp. Perhaps felt, cloth, an old innertube etc. to prevent the damage.

    I would think that repeatedly bottoming out the shock would be just as bad. However, I'm not that familiar with the internals to know if this is true or not.

    Regards,
    Marc
    LocoMoto

  15. #15
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    Quote Originally Posted by LocoMotoMan
    You could wrap your shock shaft with something tha twon't mar it when you tighten up the hose clamp. Perhaps felt, cloth, an old innertube etc. to prevent the damage.

    I would think that repeatedly bottoming out the shock would be just as bad. However, I'm not that familiar with the internals to know if this is true or not.

    Regards,
    Marc
    LocoMoto
    There's no way you're going to get a hose clamp to hold against a shock activating on a FS bike. If it's an air shock The shaft is coated in Teflon, if it's a coil-over the shaft is only about 1/8" thick and you'd never get close to enough clamping force. The activating force on a rear shock is extremely high. My 4" bike uses a 900#/inch spring for a 1.5" stroke (which means that I've exceeded 1350lbs of force on the shock when it's bottomed out.

    Anything that tight will scratch the stanchion on an air shock which will cause a $100+ rebuild at the factory, Trying it would probably damage the shaft on a coil-over too which might have equally bad effects.

    Shocks are designed to be bottomed out on a regular basis, they are designed to use all the travel and in order to do that they have to bottom out.

    Unless I was being chased by rabid flesh eating zombies or something equally bad I would walk out and chalk it up to experience. I'd rather spend a few hours hiking out than trash my shock and have to spend way more time off the bike plus significant money to get it repaired.

  16. #16
    Nat
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    Quote Originally Posted by Brandon
    There's no way you're going to get a hose clamp to hold against a shock activating on a FS bike. If it's an air shock The shaft is coated in Teflon, if it's a coil-over the shaft is only about 1/8" thick and you'd never get close to enough clamping force. The activating force on a rear shock is extremely high. My 4" bike uses a 900#/inch spring for a 1.5" stroke (which means that I've exceeded 1350lbs of force on the shock when it's bottomed out.

    Anything that tight will scratch the stanchion on an air shock which will cause a $100+ rebuild at the factory, Trying it would probably damage the shaft on a coil-over too which might have equally bad effects.

    Shocks are designed to be bottomed out on a regular basis, they are designed to use all the travel and in order to do that they have to bottom out.

    Unless I was being chased by rabid flesh eating zombies or something equally bad I would walk out and chalk it up to experience. I'd rather spend a few hours hiking out than trash my shock and have to spend way more time off the bike plus significant money to get it repaired.

    I think the concept of using a hose clamp on a fork was brought about by some well-meaning author in a magazine (who maybe never even tried it). The article in which I read it covered the topic of field fixes to get you home, and this fix specifically addressed the question, "What if I blew a fork seal out on the trail?" After that, people passed the idea along. I wonder if anyone has ever actually tried it? I wonder if anyone has ever blown a seal enough to make the fork collapse? A little oil leakage is the most I've ever had go wrong with a fork on a ride, and only on one leg at that.

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