Holes on rear break pistons

Discussion in 'Crazy-Awesome almost Dakar racers (950/990cc)' started by keener, May 18, 2014.

  1. keener

    keener Speed changes you.

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    This is a photo if rear break caliper of my 04 950 adv.

    I have never seen anything like this.

    There is no leak, break works fine.. Is this going to cause any issue? uploadfromtaptalk1400450900570.jpg
    #1
  2. charlie264

    charlie264 Long timer

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    Just covers over the piston...some brakes just don't use um...not leaking fluid I wouldn't worry
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  3. gefr

    gefr Life is a trip

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    Has no specific use but to cover the "tube"-piston opening.
    Cheers
    #3
  4. keener

    keener Speed changes you.

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    thx guys, I put a bit of caliper grease and buttoned it up.

    I rode in a ton of muddy trails in the last couple of week.

    Sent from my LG-D803 using Tapatalk
    #4
  5. spafxer

    spafxer Long timer

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    They do help prevent heat transfer into the brake fluid....
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  6. Bowber

    Bowber Been here awhile

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    I think their main use is to stop the piston filling with dirt and water and they also help insulate the piston from the pad heat.

    Steve
    #6
  7. keener

    keener Speed changes you.

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    thank you.

    whats the best practice to prevent this? grease will be washed off quickly.

    Sent from my LG-D803 using Tapatalk
    #7
  8. ADVill

    ADVill Been here awhile

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    JB Weld and sand it flush?
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  9. HeatXfer

    HeatXfer Bad knees

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    Looks like water got in behind them and started corroding the faces from the inside-out.(?)
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  10. gefr

    gefr Life is a trip

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    It corroded.
    Cheers.
    #10
  11. keener

    keener Speed changes you.

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    it didn't look like the caps are steal. They seem to be some kind of plastic.

    I think the vibration of pads sanded the ends in combination with sand from mud. Pads were worn 100%. So much that one fell off from one end by itself. They were just not the right pads for mud.

    The springs are supposed to prevent this I guess ,but not when pads wear that much?!

    new kind of pads are in and there is no play.
    #11