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  1. #1
    AllMountain+CwmcarnUplift
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    Formula K18 Bleed Problems

    Hi there. Ive put this in the Brake Time section but have had no replies. So as fellow All Mountainists I hope someone will help here.

    Ive just dug out my Cube Fritzz from the back of the shed after riding my hardtail through the winter. So i decided to give it the once over and some new brake pads.

    The front is very sharp and responsive but My problem lies with the rear.

    This is the first time im changing the front pads but the second time for the rear. I had to push out the pistons (using the bleed valves) on both because the disc/rotor would not fit.

    After doing this the front was fine but i had to bleed the rear. The front is spot on but the rear is still spongey. I was wondering would this be caused by the rear disc/rotor being worn more or is there another cause?

    I did read some where about something in the lever need changing?

    If i can not find a fix im going to have to pay ro get it done in my LBS. but i would prefer to do it myself
    If your not falling off, your not riding fast enough!

    Cube Fritzz 2008

    GT Aggressor XC 1

  2. #2
    Biking Like Crazy!
    Reputation: blcman's Avatar
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    Probably need to bleed the rear brakes. You need either an Avid or Formula bleed kit. About $35.
    The longer hose has more fluid and hence more chance for air or moisture to affect the brakes.

  3. #3
    mtbr member
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    Raise the rear of the bike and then do the rear bleed by simply screwing on the bleeder syringe (no entrapped air in the hose) and pulling on the syringe plunger - more air should come out. Then unscrew with light pressure on the plunger and cap off rear bleeder. The rear brake is always going to feel spongier than the front because of the longer hose.

    Have FUN!

    G MAN
    "There's two shuttles, one to the top and one to the hospital" I LOVE this place!!!

  4. #4
    AllMountain+CwmcarnUplift
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    blc i had already bled the rear.

    Thanks G man i'll try it.
    If your not falling off, your not riding fast enough!

    Cube Fritzz 2008

    GT Aggressor XC 1

  5. #5
    mtbr member
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    Read the formula instructions again and follow them exactly. What needs to be done near the end is to pull the lever and pull on the plunger on the lever. You get more air out. Mine had the same issue.

    If you want firmest feeling rear brakes, switch the hose to the Oro Kevlar one. It helps on that spungy feel. I can tell a little between my front and rear on feel, but mine is ok for me.
    Lead by my Lefty............... right down the trail, no brakes.

  6. #6
    Biking Like Crazy!
    Reputation: blcman's Avatar
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    Quote Originally Posted by DIESELindustry
    blc i had already bled the rear.

    Thanks G man i'll try it.
    Your OP didn't mention that you had bled the brakes, only replaced pads and pushed the calipers out.
    Go to YouTube and type in Avid brake bleed and at least try the preparing the syringe part.
    You'll be amazed at the amount of air that is in brake fluid.
    I've also just followed their bleed instructions and they worked for my K-24's!.

    PS my friend just bled his and it took 2 trys!.

  7. #7
    mtbr member
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    Actually the Oro sintered pads give the best feel and braking power but cause squeel. You can get around that by running one sintered and one organic pad in each caliper (trick I learned from Adam Craig). Do that and get the Oro levers (better for one finger braking) and your K18's get transformed into amazing brakes!

    Have FUN!

    G MAN
    "There's two shuttles, one to the top and one to the hospital" I LOVE this place!!!

  8. #8
    100% fuzz, 0% melody
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    I've been using K24s for 4 or 5 years and sometimes when the pads need replacing I have to do a bleed... and sometimes I don't. There doesn't seem to be any rhyme or reason to why the bleed is required.

    Like you experienced, I've had to replace both sets of pads -- but only needed to do one bleed.

    If you use the dual-syringe bleed kit provided by Avid or Formula (same fittings etc) and follow the directions from Formula or Avid (again same, essentially) you shouldn't have much trouble with the bleed. Just be patient. The isolated purges are the key to removing all the little bubbles in the caliper and the master cylinder/lever assembly.

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