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  1. #1
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    Skyhawk bad fork sound.

    Hey all really enjoying my new Skyhawk. Learning all this stuff from scratch and I have what I'm sure is a noob question. When I pull up forcefully to get the wheel up over an obstacle it the fork makes a really loud clanging sound. I guess the opposite of it bottoming out. So I guess it sounds like the fork is topping out? Is this normal? something to be concerned about?

  2. #2
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    Skyhawk bad fork sound.

    Quote Originally Posted by kope007 View Post
    Hey all really enjoying my new Skyhawk. Learning all this stuff from scratch and I have what I'm sure is a noob question. When I pull up forcefully to get the wheel up over an obstacle it the fork makes a really loud clanging sound. I guess the opposite of it bottoming out. So I guess it sounds like the fork is topping out? Is this normal? something to be concerned about?
    Hi, welcome here

    Your fork shouldn't be topping out like this, it means the rebound (return speed) is too fast, so you have to increase the damping to slow it down and prevent harsh top out. You didn't mentioned which fork your bike was equipped with, and since I'm not too familiar with airborne's bike specs, I can't tell if your fork as this kind of adjustment and if it does, wether it's located on top or bottom of the left or right leg.

    But to answer your question, no this is not normal and yes you should be concerned about it. Yes it's an easy fix and no you should not be having any trouble getting rid of this once you learn the proper way to tune your particular fork (check the model and look up the manual online or ask a friend of yours/mtbr forums).

    However, most entry level forks nowadays comes with this basic setting, so if you'd post the model and a pictures of the different dials knobs if you can't identify which one as the rebound adjust, I'll be pleased to guide you trough this.

    Quote Originally Posted by NicoleB28 View Post
    topless. that's what all mtb girls do. we go ride, get topless, have pillow fights in the woods, scissor, then ride home!

  3. #3
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    It's an XCM, David.
    Earnest Hemingway once said "The world is a fine place and worth fighting for." I agree with the second part.

  4. #4
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    Skyhawk bad fork sound.

    Quote Originally Posted by bleedinblue View Post
    It's an XCM, David.
    Alright, so this is your bike : http://www.airbornebicycles.com/prod...2-skyhawk.aspx

    And this is your fork : SR Suntour XCM 100mm

    Now, there are many declinations of this model, so if yours has rebound adjust, it should be the same as pictured below. If so, then simply turn the knob to make the fork slower. If not, the only way you can reduce top out with a coil fork is to change the oil to a heavier weight to make the fork slower or if using an air sprung fork, to use less compression pressure (the "elastic" setting of the fork) to reduce the return force, and also change the oil to a heavier weight if you can't get it right with the air springs.

    Skyhawk bad fork sound.-imageuploadedbytapatalk1365569498.317626.jpg
    Quote Originally Posted by NicoleB28 View Post
    topless. that's what all mtb girls do. we go ride, get topless, have pillow fights in the woods, scissor, then ride home!

  5. #5
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    Thanks for the help. Much appreciated. It does not have any dampening. Just two preload adjustment knobs which I haven't messed with. I'm pretty sure its the most basic model.
    Its about a month old and hasn't seen any dirt. (fingers crossed for this sunday). So this has been around the neighborhood going off curbs and such.

    Maybe I'm just super strong...lol.

    From what I've come to understand, adjustment to the preload wouldn't effect this correct? I didn't even realize there was oil in there...lol.. just thought it was spring only.

    I'll take a closer look at it today to see if I can provide any more info that might be relevant I'm pretty mechanically inclined, but new to modern bikes, so I'm willing to dive in if this is something I can remedy myself.

    Thanks again.

  6. #6
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    Skyhawk bad fork sound.

    No problem. The fact your fork tops out has nothing to do with your strength, it's simply a lack of rebound damping to smooth the recoil of the springs. Yes there is oil to keep everything lubricated and also to smooth the stroke of the fork, by passing trough small holes. In short, the rebound adjust setting is simply a valve in one if the legs that regulate how much oil can flow trough the hole, from very little (slow) to full volume (fast). Forks without a rebound adjust simply have a pre-determined hole size to allow a somewhat normal flow, and the only way to increase or decrease the oil flow is to change the oil to a heavier or lighter weight (viscosity).

    This is pretty easy to do, as most bike maintenance is. In short, hook the bike on a working stand or something to hold it tight, remove the front wheel and most likely the front brake caliper too, put a large oil pan under the fork, then unscrew the top caps to take out the coil springs. Then unscrew the bolts under each legs and then thread them back in maybe 3-4 turns. Using a rubber hammer, hit the screw in to break the crush washer seal and take off the bolts and let the oil drain in the pan. You can cycle the fork up and down to help get the most oil out of it. Once you're done, put back the bolts tight, and fill the legs with new oil (heavier) as specs by suntour, then cycle slowly the suspension to work all the air out, put back the springs and screw the top caps and re-install your front wheel and brake caliper, after cleaning up all oil residues using isopropyl alcohol.

    You can find the oil weight and oil volumes specs in the Suntour user manual of your fork.

    Tools should be a 21 or 24mm wrench (or around this size) for the top caps, usually a 5mm Allen key for the shaft bolts, a rubber mallet to hammer in the shaft bolts (you can leave the Allen key in the bolt heads to prevent hammering the fork instead) and a few good rags, oil pan (or anything at least 2x2ft to be sure to catch all the oil spill), new oil and a bike stand (I hooked mines with chains from the ceiling since I work in my basement). And it should also be a 5mm Allen key to unbolt your brake caliper.

    Hope that helps
    Quote Originally Posted by NicoleB28 View Post
    topless. that's what all mtb girls do. we go ride, get topless, have pillow fights in the woods, scissor, then ride home!

  7. #7
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    Are you sure it's not cause I'm super strong? dang it.

    Excellent guide. Thanks for the effort. While I'm confident I can do it, I'm on the fence. I was planning on upgrading the fork through suntour as soon as I replenished my fun money which will be Fri.
    But I was also planning to hit the trails this weekend.

    Could any real damage be done to the bike if its not remedied? The trails will be very beginner.
    Is this odd to be going on with what's essentially a new fork?

    I'll let you know how it turns out.Thanks again.

  8. #8
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    I've since upgraded to the Suntour Raidon but also had the same as you with my XCM.

    To stop it happening I slackened off the pre-load all the way on both sides and then tightened them equally on both sides until I was happy with the stiffness.

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