Rear brake - piston bad or just need to adjust travel?

Discussion in 'Crazy-Awesome almost Dakar racers (950/990cc)' started by DanoPDX, Nov 12, 2012.

  1. DanoPDX

    DanoPDX monkey piss

    Aug 14, 2007
    Stumptown, OR
    Both the free play and the engaged travel on my '08 990A's rear brake pedal have increased significantly. Based on general experience, is there much reason to think my brake piston is stuffed, or is it more likely I just need to adjust the pushrod, etc?

    Measured at the front of the pedal, free play is 7 mm. Additional travel while engaging the brake is max of 22 mm.

    Not finding any specs for "correct" travel, I measured a new 990A at the dealer. It had 3 mm free play, and 17 mm additional travel.

    My main concern is with having to push too far down to engage the brakes when standing on the pegs. Otherwise, the brakes feel fine - not spongy or weak.

    I've snugged the brake pedal down REAL tight a few times, while breaking my CS sprocket nut free. Maybe something has slipped on the piston as a result? Nothing's leaking though.

    I'm due for a fluid change, so if I need to rebuild the piston, now's the time. I'll also disassemble the lever, to make sure nothing's reamed out, but it doesn't feel sloppy.
  2. Tosh Togo

    Tosh Togo Long timer

    Nov 21, 2010
    Change/bleed the fluid, then get back to us. :D