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Hayes disc brakes problem after new pistons

bing gordonbing gordon Posts: 662
edited May 2015 in MTB workshop & tech
I recently bought a second hand mtb but front Hayes Nine disc brake was jammed solid. I have never had disc brakes so I decided to tackle it myself and after further investigation decided to order and fit new pistons o ring seal set , pads, and o rings , and new brake fluid then I know there it's had a full overhaul/service.
I stripped down the brake and installed the pistons and using a bleed kit I put new brake fluid in making sure to hold the lever up and no air.

The problem I'm having is, I have to pull the brake right to the handle bars , very hard for the front to work were as the untouched back brake you get a bite by pulling it 1/2 way to the bars. I followed the guide a few huides on youtube from singletrack.com but after 4 attempts bleeding the brakes they still don't fully bite. I've got a feeling only one side of the pistons actually comes out, how do I solve this ?

Posts

  • The RookieThe Rookie Posts: 27,747
    I've had this when in this situation, it can take a while for the seal to hold the piston out with the pad close to the disc, 3 options
    1/ just ride it and it will probably sort itself out
    2/ keep pumping the brake weever you are near the bike to encourage
    3/ remove the front wheel so the pistons come out further, then hopefully won't retract too far.
  • bing gordonbing gordon Posts: 662
    The Rookie wrote:
    I've had this when in this situation, it can take a while for the seal to hold the piston out with the pad close to the disc, 3 options
    1/ just ride it and it will probably sort itself out
    2/ keep pumping the brake weever you are near the bike to encourage
    3/ remove the front wheel so the pistons come out further, then hopefully won't retract too far.

    OK will do , I 'll give it a go and see if the left side piston losens the up abit
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