brake system rebuild
Welcome guest, is this your first visit? Create Account now to join.
  • Login:

Welcome to the CBRXX.com.

Register ButtonIf this is your first visit, be sure to check out the FAQ by clicking the link above. You may have to register before you can post: click the register link above to proceed.


Results 1 to 8 of 8
Like Tree6Likes
  • 1 Post By cbrpaul
  • 3 Post By TheDuck
  • 1 Post By cbrpaul
  • 1 Post By Partsguy

Thread: brake system rebuild

  1. #1

    Member #
    38023
    Join Date
    Jul 16 2019
    Posts
    99
    Liked
    18 times

    brake system rebuild

    hi Guys
    in a earlier posting i had mentioned that i had gotten a long -in -the -garage bb for a small outlay
    the final thing i had to attack was the brakes
    the fluid had been sitting for about 10 years
    what happens is that
    the water vapour in the fluid starts to attack the steel in the calipers ( yes they are cast steel not alloy )
    the fluid coagulates and becomes a goo especially in the different master cylinders
    the relief valves at the back and front become embedded and stuck
    the pistons freeze onto the seals
    the slider pins dry out and freeze up
    the cross pins seize in the holes

    the dcbs system is probably the best analogue system you can find ( eg pre abs )

    when its in full order its very good at sharing the braking force as a primitive anti skid device

    but its complex with long hose runs and lots of nice places for goo and bits to accumulate
    when its far gone a flush is of no use as the good will not move out
    the only way to do it ( and i found out the hard way ) is to take off all the masters and relief valves and clean them out
    particular attention needs to be paid to the zamak spacer that collects goo and the tiny tiny relief holes that get blocked
    also the nylon filter and anti return valve on the side of the fork mounted mater cylinder needs to be removed ( not easy ) and cleaned

    the proportion valves need to be cleaned and rinsed very carefully
    the 2nd master cylinder needs to be reassembled very very carefully and the c clip has to click into place
    no click means its not fully seated and will release under pressure --- not good

    if you do that then you have a fighting chance to get the cbs working again
    for the flushing the factory procedure is ok but you will need a device to create a partial vacuum in the system to coax the fluid to come to the nipples
    i call it " sucking the nipple " sounds rude but it isnt
    i use a large syringe with flex hose to create the vacuum and when fluid starts to dribble out i then start to pump the appropriate lever to force the fluid through
    usually i let the bike sit overnight once flushed and then do a quick second flush the next day to force out any recalcitrant bubbles

    then i do several km of stop and go runs with repetitive braking to bed everything in and get resistance and bite in the levers
    have fun
    paul
    Ausblackbird likes this.

  2. # ADS
    Sponsor
    Join Date
    Always
    Posts
    Many

    CBRXX.com is the original Honda CBR1100XX Super Blackbird community! Registered Users do not see these ads. Please Register - It's Free!


  3. #2
    Supercharged Mod
    Member #
    4781
    Bike(s)
    99 Bird. 03 Supercharged KwakBird. DR800 Big
    Join Date
    Oct 25 2008
    Location
    UK South West
    Posts
    12,439
    Liked
    3994 times

    Re: brake system rebuild

    Good words Paul
    Quote Originally Posted by cbrpaul View Post
    the 2nd master cylinder needs to be reassembled very very carefully and the c clip has to click into place
    no click means its not fully seated and will release under pressure --- not good
    Non engineering nerds might not know that the internal circlip used has one 'sharp' and one rounded edge. The internal groove in the cylinder is also similarly shaped.
    So if the circlip doesn't snap into place turn it over and try again and it will almost certainly snap into place.
    CBRDEAN0, Punts and Ausblackbird like this.
    Full of Hot air? Intercool yourself............ you know it makes sense

  4. #3

    Member #
    38023
    Join Date
    Jul 16 2019
    Posts
    99
    Liked
    18 times

    Re: brake system rebuild

    in fact the face plate it seats against has an annular groove that traps the tangs if its fully home so its difficult to unclip
    big of a b--er to release it..
    TheDuck likes this.

  5. Remove Advertisements
    CBRXX.com
    Advertisements
     

  6. #4

    Member #
    616
    Bike(s)
    99 CBR1100 Race version
    Join Date
    Dec 23 2006
    Location
    near London,Canada
    Posts
    4,731
    Liked
    818 times

    Re: brake system rebuild

    Yep.Remember to keep your brake and clutch fluid clean everyone or you too can be a big tub of goo.

    I'm so glad I don't have linked brakes anymore.
    Ausblackbird likes this.

  7. #5

    Member #
    38023
    Join Date
    Jul 16 2019
    Posts
    99
    Liked
    18 times

    Re: brake system rebuild

    question
    the system is now bled and seemingly " water tight " so to speak but the pdeal is spongy
    if i pump is 2 times is hardens up
    is that an issue?
    i am wondering if i have residual air in the pipe work from the 2Nd master to the back caliper that wont flush out ??
    paul

  8. #6
    Older wiser and sorer
    Member #
    15988
    Bike(s)
    2000BB
    Join Date
    Apr 27 2013
    Location
    australia
    Posts
    1,395
    Liked
    668 times

    Re: brake system rebuild

    I found a cheap vacumn sucking device in the form of a manual sucker bottle for lawn mower oil. Get the right hose diameter and it is very good at pulling the brake through. Far cheaper than specific brake vacumn pumps which are quite dear.
    STAY ALIVE BE DROPBEAR AWARE.

  9. #7
    Supercharged Mod
    Member #
    4781
    Bike(s)
    99 Bird. 03 Supercharged KwakBird. DR800 Big
    Join Date
    Oct 25 2008
    Location
    UK South West
    Posts
    12,439
    Liked
    3994 times

    Re: brake system rebuild

    There will be some air in there cbrpaul if you have a spongy pedal. This can be a pain to get out.
    Steps to take.
    1. Disconnect the secondary cylinder where it attaches to the caliper. If you have another pair of hands handy (a helper) you can bleed the rear caliper by pumping the secondary push rod the air will eventually come out. If alone leave the bleed nipple open (with tube on going into a jar) and just pump the secondary cylinder a few times. Chances are that when you first pump the secondary you will not feel any/much fluid resistance. When you feel fluid resistance (it is very noticeable) stop pumping.

    2. The other 'trick' is to disconnect the rear caliper and hang it in the relevant position (one for each nipple) where the nipple is at the highest point, this ensures the air finds its way out.
    Full of Hot air? Intercool yourself............ you know it makes sense

  10. #8

    Member #
    38023
    Join Date
    Jul 16 2019
    Posts
    99
    Liked
    18 times

    Re: brake system rebuild

    hi Duck
    thanks for the info which i followed with the help of my lad
    i have now got 99 pct of the recalcitrant air out of the rear system
    so its about as good as ill get
    strangely enough the residual bubbles came out of the rear cylinder nipple and not the mid
    so pretty much good for the road
    got a bagster with backpack coming in later in the week ( bought 2nd in germany of eBay small ads ) and a small carrier for bagage on the tail
    then off we go…
    have fun
    paul


 

Sponsored Links

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •