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  1. #1
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    Question about SAG.

    This may be a dumb question for most of you, but I'll ask any how. If you have a 6" travel bike (or whatever size travel for that matter) and you set the sag for 25% of the travel. Are you not losing that 25% of the travel in your suspension? I'm confused.

  2. #2
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    Reputation: Speedub.Nate's Avatar
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    Well, yes and no.

    In a static sense, you'd be correct: your six inches are reduced to 4.5. But suspension is dynamic, and while in motion your properly set-up suspension will be using all six inches.

    If you didn't set any sag, you would likely be riding a very harsh suspension and might not have full use of your available travel.

    Also consider when you've got your wheels off the ground, or are riding fast terrain that drops away from you: Your suspension extends fully (zero sag) and is there for you as you return to earth. With zero sag, your wheels would leave the ground much more often, and landings would be harder.
    speedub.nate
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  3. #3
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    Cool, thank you. That was kind of what I was thinking but wasn['t sure. Thanks for helping out a new guy.

  4. #4
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    Quote Originally Posted by Speedub.Nate
    Also consider when you've got your wheels off the ground, or are riding fast terrain that drops away from you: Your suspension extends fully (zero sag) and is there for you as you return to earth. With zero sag, your wheels would leave the ground much more often, and landings would be harder.
    You also have no control over the wheel when it leaves the ground, and your bike can end up going in a different direction than where you're expecting or trying to go. A little sag can keep your front and back ends from jumping around on you, giving you much more stability and control. When your wheels start bucking, your going pretty fast and keeping your wheels on the ground can keep you from crashing.

  5. #5
    Your bike is incorrigible
    Reputation: Guyechka's Avatar
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    25%???

    Whoa! I thought I was setting my sag on the low side at 33%.

    Yeah, I've had the same feeling: I'm losing 2" of sag. But then I ride down something rough and realize that I am using the negative stroke just as much as the positive stroke (I guess this is the terminology). The wheel tracks over nasties at high speed, and I like it.

  6. #6
    The Ancient One
    Reputation: Steve from JH's Avatar
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    Braking

    In addition to the benefits of running sag already mentioned, it helps when braking.

    Weight naturally shifts to the front when the brakes are applied and if no sag is run the rear shock becomes in effect pre-loaded. That means any bump must overcome the pre-load before the shock can compress. The bike will bounce like a hardtail over small bumps.

    Automotive suspension engineers call the extension from losing sag "droop travel". I love that term.
    "Don't criticize what you can't understand."

  7. #7
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    Thanks a lot for all the help. I also run about 30% sag, but just picked 25% for simplicty here is my question. The negative and positive stroke explanation helped me getting a understanding. Thanks guys ,

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