how often to bleed brakes?

KnightofCydonia
KnightofCydonia Posts: 957
edited July 2009 in MTB workshop & tech
I wondered if there was some sort of law into when to bleed them, is it just down to personal feel etc or is it indeed a good thing to do say every 3-4 months? I've had my bike since march now and the back is beginning to feel a bit weaker than it was previously, almost spongy on the lever which from what I've read before indicates bleeding required (usually then pads changed if not?)

cheers
Start Weight 18st 13lbs March 2009
17st 10lbs August 2009
17st 4lbs October 2009
15st 12lbs December 2010

Final planned weight 12st 7lbs

Comments

  • supersonic
    supersonic Posts: 82,708
    When they need doing. Or once a year.
  • thanks sir :) I'm going to see how they go but they're feeling less powerful. Fortunately I need to take the bike in for a spree of things I couldn't afford when I bought it soon, better pedals that don't hurt my feet, a good lock, a nice helmet, couple of other bits, so i'll ask them to fit it all & check themselves. Experts > Me :lol:
    Start Weight 18st 13lbs March 2009
    17st 10lbs August 2009
    17st 4lbs October 2009
    15st 12lbs December 2010

    Final planned weight 12st 7lbs
  • nicklouse
    nicklouse Posts: 50,675
    if they are feeling less powerful then they do NOT need a bleed.

    they only need a bleed if the lever feels spongy with the rotor not being displaced by the pads.

    once a year is OK but even then not always needed.

    sometimes brakes can need a bleed at the end of every DH run if they rider has been dragging the brake causing them to boil.

    what is the recommended brake fluid change time on a car?
    "Do not follow where the path may lead, Go instead where there is no path, and Leave a Trail."
    Parktools :?:SheldonBrown
  • Don't ask me, i don't drive yet!

    It's more a case of the lever feels like i'm pulling it further back than usual. At the start I barely had to pull and had a good stop, now they're coming 2-3x as far and it's not engaging very well at all. hmm :?
    Start Weight 18st 13lbs March 2009
    17st 10lbs August 2009
    17st 4lbs October 2009
    15st 12lbs December 2010

    Final planned weight 12st 7lbs
  • nicklouse
    nicklouse Posts: 50,675
    do the brakes have any adjustment?

    are the pads moving further than before? IE have not self adjusted.

    are the pads worn out.

    what are the brakes.

    try adjusting the lever reach adjuster and they should come back. then adjust the reach agin to suit.
    "Do not follow where the path may lead, Go instead where there is no path, and Leave a Trail."
    Parktools :?:SheldonBrown
  • Hayes Stroker Ryde. I've never fiddled with them tbh, too afraid of doing something that will make them explode or something!
    Start Weight 18st 13lbs March 2009
    17st 10lbs August 2009
    17st 4lbs October 2009
    15st 12lbs December 2010

    Final planned weight 12st 7lbs
  • jedi_master
    jedi_master Posts: 888
    Here's a video on bleeding the strokers http://www.youtube.com/watch?v=KpdTKzgoVGk
    You might also want to by one of these http://www.chainreactioncycles.com/Mode ... delID=7486 like it shows in the video as you don't get on with the bleed kit to help hold the fluid hose on the bleed nipple.Ordered one myself. With out it the hose seems to come off very easy and you end up with fluid on the floor.
  • duron1
    duron1 Posts: 2,475
    |In a car, brake fluid is changed every 2 / 3 years usually. Avid say veery 2 uears for theres. As the system is sealed, its quite hard to get any air in the system. Also ,when you bleed the brakes, if the fluid comes out darker, then it makes it deff needs changing.
    Commuter: Saracen Vex '03 (Full XT drivetrain, Rockshox Tora 302 80mm, Conti Touring Plus..etc)

    MTB Hardtail: Orbea Satellite - Team Colours '08 (Full XTR drivetrain, Reba Teams, XC717s - Hope Pro II, Fire XC Pro 2.1...etc).
  • 1st_aide
    1st_aide Posts: 11
    Check out the videos on the hope website.
    It could be pad ware, this would account for the longer lever travel.
    Also check the pistons are pressing the disk evenly, there is a video on this on the hope website.
    I change my fluid less than once a year, but it might depend on how much you ride etc.
  • dynamis_dk
    dynamis_dk Posts: 428
    I had no preformance issues with my Hope M4's for 3 years without being bled. Was doing about 30 mile a week on them so not getting massive use but it goes to show they don't need a routine bleedas such. Only reason they got bled this time round was to change to goodridge hose :)
  • Got the feel back when I fixed a puncture yesterday and compressed the lever a couple of times before re-fitting the wheel. Still don't feel 100% but I mostly use my front which seems fine so I'll wait until my 6 month service if I can, and ask the shop what it is, if it's something as simple as pads (I'm not totally sure i bedded them in as well as I could being a first time user) then we shall see :) Bleeding I think I'll wait again, get the expert advice when they feel it and maybe ask to watch so I get an idea of how to do it in the flesh.
    Start Weight 18st 13lbs March 2009
    17st 10lbs August 2009
    17st 4lbs October 2009
    15st 12lbs December 2010

    Final planned weight 12st 7lbs