rear brake not playing ball

Guru's,

After having a non excisting rear brake for some time I thought it would be best to get it sorted, master cylinderseems to function and no air coming out when I bleed the system.

How ever I have to push the brake lever very far down befor I feel any braking???????


Any ideas? Braded hoses seem intact

Yup take the caliper off and tease the line out from its clips or retaining bracket the lift as straight up in the air as you can get it , bleed nipple uppermost . put a piece of wood or something between the pads then put a heavy weight (around 5kg's) on the brake pedal , leave over night.

Next day bleed as normal, as a clue I remove the exhaust can and bolt the caliper to that. The when not riding the bike just leave that 5 kg wait hanging off the pedal.

I kept the caliper up high all last night but made no difference

Ill try putting the weight on, cheers

Dont mean to speak out of turn. I have had trouble with calipers front and back after a total rebuild, new pads and fluids etc... Just persistence needed to ensure the air is all out. Sometimes the passage of time may help ! The fronts were a complete pig...and reverted to spongy . Eventually I got em done although I will not hesitate to remove a difficult system and do it on the bench...something about all that fecking fluid and paint and rubber and the whole bloody mess. It bugs me , so onto the bench it is ! lol !
The rear, I simply adjusted the freeplay in the end - there was nothing wrong with it. Unless it is going noticeably spongy overnight for instance, and requires pumping up to reach a working pressure - you gotta reckon it's ok ? Bear in mind that if the brake action is very low ( at the end of pedal travel) then the bleeding process is less than optimal also....adjust the freeplay and bleed again!
HTH !

Tim,

You are scaring me when you say adjusted freeplay on the back brake.

Kiwi_rsvr said:

Tim,

You are scaring me when you say adjusted freeplay on the back brake.

Click to expand...

:stupid

Be really careful when you adjust that rear brake piston actuator.
Make sure you have the specified free play (and then some)
If you get it a smidgeon too tight, the pads will drag, causing friction, which causes a build up of heat, causing the fluid to expand, increasing pressure in the system which will result in the back end locking up without warning....

alls I have done is move the pedal action higher FFS ! Standard adjustment on MC pin....
You guys like to make a drama out of a molehill huh ! :jack

caliper must be as high as possible, then just bleed it in the simplest way possible.
1. Length of tube on the bleed nipple which is sitting in a container suitable for receiving brake fluid
2. push the lever down
3. crack the bleed bolt
4.do up the bleed bolt
5. let the lever go
6. repeat steps 2-5 until the lever goes hard, making sure to keep the reservoir filled above the minimum line or more air will get in and you'll have to start again..

Of course the whole process counts on the caliper pistons not being stuck. Give them a clean and a grease and that'll make a world of difference. Most people don't use their back brake much- especially on milles as they are often only used for fast road riding, not sitting in traffic or shuffling around on slippery surfaces. For this reason the calipers do seize through lack of use and when you need them, they haven't been paid any attention to and won't work.

As mentioned above, there should be a little play at the lever, that's not only acceptable but recommended if you don't want the brake to self apply when the fluid gets warm

Then use the correct terminology you muppet !

Its easier to simply avoid the forum I guess...theres always one know all plonker isnt there !
Who are kiddin man ? And who does it help? Really ? Scaring you...no explanation why...just smart arse BS...grow up ! And direct your snidey comments elsewhere man !

TimR V2 said:

Its easier to simply avoid the forum I guess...theres always one know all plonker isnt there !
Who are kiddin man ? And who does it help? Really ? Scaring you...no explanation why...just smart arse BS...grow up ! And direct your snidey comments elsewhere man !

Click to expand...

Not my fight, but I think it's you who needs to grow up fella. A perfectly valid post from Kiwi given your vague description. Tifa explained the fears. Man

I thought I tried to explain it ....if posting requires word perfect terminology from layman..I dont want to be here frankly.
Thanx for wading in Paul...a mature response displaying a clear grasp of the issues of internet abuse...
I dont have these problems in real life...
Its not the first time this member has knit picked a post from me. And he too has waded in showing he doesnt read the post...Im not happy about it...but I got better things to do than argue the toss with complete strangers..let alone people who are not directly involved.
Internet. :roll
Excuse me for breathing....!

@ Admin - Flame wars...not here ! Im done. :thumbup

Better things to do, but you keep posting... :roll And arguing with someone that's been here a lot longer and contributed a lot more, no less... Funnily enough, correct terminology is quite important. It's the difference between knowing your ****, and knowing you're ****.

Back to the topic at hand. After trying numerous bleeding techniques to fix the rear brake issue, replacing the master cylinder and the brake fluid to 300° stuff mine was still *****. From the advice of the guru's here the options were to replace the rear sets and mount the master cylinder vertically, as it should have been designed initially. Alternatively you can do a straight swap for the master cylinder from an Aprilia Shiver. Or you can hang a weight off the rear brake every third or fourth night. All of these will solve the issue that's plagued us all, the dreaded rear brake...

Hang the weight occasionally. Solves it for a while.