07 990 Brakes-No Bueno

Discussion in 'Crazy-Awesome almost Dakar racers (950/990cc)' started by GoGoGavin41, May 6, 2013.

  1. GoGoGavin41

    GoGoGavin41 Isn't this that guy?

    Joined:
    Nov 29, 2009
    Oddometer:
    852
    Location:
    "America's Finest City" ...wait, what?
    So, I went and picked an 07 990a up yesterday from an inmate in San Fran. Very happy with the bike, the ride definitely sucked back to San Diego (ridiculous cross winds, dust storms, LA traffic, etc). I believe the bike has been sitting a while and thought maybe these brake issues would clear up after I had ridden a while but they're persisting.

    Front brake: Pull is a little squishy the first 2-3 pulls, then gets firm to what I would think is the right pressure. Now don't get me wrong, the thing still stops HARD with the front discs, but the first pull or two (while sitting still) you can get the lever almost all the way to the bar.

    Rear Brake: Well, there just isn't much. Putting "emergency" level pressure (as hard as I can push down on it) seems to provide about as much stopping power as the rear drum on my 1980 Tomos Moped. I noticed this when I tried to engage the ABS and the brake won't provide enough friction to break grip.

    Both sight glasses show plenty of nice, clear fluid, the bike only has 11k miles, and all the wear parts still have lots of life on them (pads, rotors). I'm thinking the front may just need to be bled, and maybe the rear got glazed over or something and the pads might need sanded and re-broken in. I've read stuff about people not putting the brakes back together correctly before, but this doesn't seem to be the case to me.

    Thoughts?
    #1
  2. FakeName

    FakeName Wile E Coyote SuperGenius

    Joined:
    Jan 1, 2007
    Oddometer:
    1,928
    Location:
    San Diego
    I'd start by bleeding them both. The front almost 100%- anytime they'll pump up, it's air in the system.

    I find the rear brake on my bike a little annoying in its travel when compared to my RFS bike. It still locks up nicely with the ABS off.

    Are the results the same with the ABS off on yours?
    #2
  3. Nailhead

    Nailhead Free at last!

    Joined:
    Apr 6, 2003
    Oddometer:
    6,406
    Location:
    Longmont, CO
    Mine did that for an entire summer.

    I bled the front system, with no improvement. I posted a thread about it, and someone suggested pushing on the shifter-side caliper with a knee to slide it back, or something like that. You might search for it, because the procedure did work-- albeit, temporarily.

    Next summer, the problem was gone, and it has not reappeared since.
    #3
  4. FakeName

    FakeName Wile E Coyote SuperGenius

    Joined:
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    San Diego
    another suggestion- use a tie-down to firmly apply the brake while parked in the garage. Turn the bars to the left so the MC is high.

    Wait overnight.

    Come back the next morning and evaluate. I've done this on my RFS bike with great success- the bubbles travel up the lines.
    #4
  5. Mr_Snips

    Mr_Snips Husky BRAAAAAAAAP!

    Joined:
    Oct 31, 2009
    Oddometer:
    356
    Location:
    Yucca Valley, CA
    I've found even with good fluid and pads the brakes are a little underpowered for aggresive street riding. they will fade. however when they are freshly bled and your on knobby tires you only need 1 finger to lock that front tire up.
    #5
  6. David37

    David37 Been here awhile

    Joined:
    May 26, 2008
    Oddometer:
    420
    Location:
    SLO County
    I have an 07 KTM 950 SE and was never really impressed with the rear brake. I bleed the brake, sanded the brake pads to rough up the surface, cleaned the caliper and used fine steel wool to rempve any glaze on the rotor. Stopping power was good but not great.

    I just purchase a vacuum brake pump from Cycle Gear (on sale for $39.99) and was able to remove all the air from the brake line and caliper. Rear and front brakes work great.
    #6
  7. DSM8

    DSM8 Where fun goes to die....

    Joined:
    Aug 1, 2005
    Oddometer:
    4,100
    Location:
    Glendora, Ca
    Fully flush the system, if it has been sitting or such then the fluid might also be a little old, it does absorb moisture over time.

    Fully drain the fluid, then reverse bleed them forcing the fluid from the calipers up to the master cyln.

    I have done this on both ABS and non ABS bikes with great success, since the fluid is moving up the lines it is allowing the air in the fluid and lines to move in the direction it wants to travel. Up.

    The tying the level back to the bars overnight is also another really good suggestion.

    Hope this helps.
    #7