mornin all
got caught in a rain storm yesty. not a prob ill jus get wet. that was until i went to pull the front brake on and it went straight to the bar without any real brakin assitance.
jus gone out to it to see and it feels as if theres no fluid in there. any ideas what mightve happened ? cos i aint gotta clue
cheers :hat10
How is the fluid level in the master cylinder?
Blown brake pipe...Look for leaks.
Worn out pads, are they down to the metal? (Score marks on the disc).
If those ok, suspect mastercylinder seals gone.(The handlebar one).
fluid levels fine, brake lines are fine, pads are good too. master cylinder seals got replaced bout a month or so ago. jus fitted some tockico 6 pots on and currently bleedin em to see what happens
I just cannot imagine how this has any connection with the rain. :5huh
Quote from: FoothillRyder on August 31, 2012, 05:21:29 PM
I just cannot imagine how this has any connection with the rain. :5huh
Somewhat puzzled about the rain!!
Was the master cylinder honed or cleaned up before replacing seals?
Have known new seals to leak when they hit the un-worn/unswept part of the bore.
Maybe bad fluid with water in it? I guess....
More critically i trust you are ok. Did you write-off your undies or were you not going fast?
well i dont know whats goin on with em. bled em up yesterday and can no longer get air out of any part of the system. tried a new set of calipers, had the lever tied back all night last night and still no brakes :BangHead.
which means im now stuffed as ive tried everythin i know and still cant get a lever.
so far i have tried :
pumpin the lever and releasin the nipple, still no brakes
pressure bleedin from the top, still no brakes
pressure bleedin from the bottom, still no brakes
usin a vacuum pump to draw fluid throo the bleed nipple, still no brakes
rebuilt master cylinder (unhoned cos i aint got a tool for it), still no brakes
another set of calipers, guess what ? .........still no brakes
im now at a point where im thinkin of rippin meself off and takin it to a dealer. :new_all_coholic
If you still have flexible hoses, not braided, perhaps you could try clamping one caliper off, and bleed the other, to see if you can isolate the fault. Its a closed system, so either there is a fault in one or more component parts , or you have air.
It can be very frustrating.
Some years ago my sister bought a car, and the front brakes would only work for about 1000miles if new pads fitted, turned out a locating pin had sheared in one of the callipers, which meant that movement of pad was restricted to just a few millimetres, took a lot of finding, and only when we finally clamped off the brakes one by one to find where the fault was.
Phil's on the right track, you have to break it down into stages until you find the bit not working. You've done well so far, establishing that there are no leaks, and no air in the system and the calipers are unlikely to be the problem as you've changed them.
Go out to the bike and pull the lever on and tie it back. Have the pads moved? If they have can you prise them back with a screwdriver or similar (carefully, don't damage anything obviously). If the pads haven't moved, or if they have but can be prised back, then the prob is in the master cylinder. I don't know without seeing them if the seal can be fitted the wrong way round but it's an idea. Also look at the valve that draws fluid from the reservoir to make sure it's not letting fluid past.
Since you have fluid moving through when you bleed them and no leaks it can't really be anywhere else.
BB is right there, as had similar before especially with pattern kits for the master cylinder.
The main seal can swell slightly with brake fluid and can cover the inlet port under normal operation but if pumped fluid is involved, will pass through the port. The brake lever not returning fully or if an aftermarket one is used then it can stop the plunger from returning fully, again covering the port.
Sometimes if the cylinder isn't honed, when the new seal passes over the unworn part of the bore, it can get damaged by the unused bore being rough.
I believe Kawasaki master cylinders are similar.
cant block off a hose unfortuantly cos i got braided lines on it. later on today im goin to try one line from the master cylinder and a loop over line from caliper to caliper. ive got it in me head the airs in the master cylinder. so im thinhkin if i take out the double banjo bolt and replace it with a single one theres less places for the air to get trapped. if they dont work ill be lookin at the master cylinder.
when i replaced the cylinder seals, genuine not oe. i still had no real improvement in the feel of the lever. so i thought that perhaps it wernt that what was causin the problems. hopefully today ill suss it
yesterday saw me remove one brake line from the master cylinder and replace it with a caliper to caliper line, i tied up the lever last night and guess what ? ive got a brake lever :thumbsup.
so im guessin that i jus couldnt get the air out of the double banjo bolt as once id swapped it down to a single line i bled it up in not time :eusa_clap
now its just a case of beddin in these new pads i got n i should finally have decent brakes :XXsunsmile
Well done mate, logic and perserverance are the keys eh? :thumbsup
Nice one. Glad you got there in the end, makes it all the more satisfying..
cheers all :thumbsup didnt last long tho. by the end of the dat the lever was back at the bar. so ive bled it again n got a bit more air out. i think this is goin t be a long slow process :sleepy1
Still sounds like master cylinder fault there.
Just saying!
Hope it doesn't rain again :XXsunsmile :eusa_clap
Quote from: metalguru on September 04, 2012, 02:18:35 AM
Still sounds like master cylinder fault there.
Just saying!
:iagree
If it was just air surely there'd be some feel? I would hate for you to find out the hard way Rybes..
well it would appear that tmora im gunna take the master cylinder off n have a good look n see whats in there. imguessin the seals are still gunna be good (?) so what am i lookin for inside there or will it stand out when i look inside ?
Its a long time since I did one so MG'LL probably have more recent info but, working from memory, take the master cylinder cover off and drain some of the fluid till its just covering the valve. Now when you pull the lever, if the cylinder is leaking you'll see/hear fluid squirting past the seal. Hope that helps!
i can say now that when ya look into the top of the master cylnder you see 2 holes. when i squeeze the lever fluid comes out of the hole on the left. squirts up as if its been in a water pistol. im guessin thats what you mean ?
Yup.... that's supposed to be going down the hose.
I love the way Mustang's standing off watching us pick through this instead of wading in and spoon feeding us the answer :ImaPoser
That's how ya learn tho :qgaraduate
i did think bout that mustangs lack of participation. was thinkin he was on holiday.
well got the cylinder off and took apart n had a look and there seems to be a patch of unshiney black stuff in there. not sure if its corrosion or not. tried cleanin it off with methanol and wire wool but its not shiftin so im guessin its corrosion of some kind.
so now ive gotta find a new cylinder n hope it was that.
Quote from: Bixxer Bob on September 05, 2012, 11:02:36 AM
Yup.... that's supposed to be going down the hose.
I love the way Mustang's standing off watching us pick through this instead of wading in and spoon feeding us the answer :ImaPoser
That's how ya learn tho :qgaraduate
:ImaPoser
Quote from: rybes on September 05, 2012, 11:34:42 AM
i did think bout that mustangs lack of participation. was thinkin he was on holiday.
well got the cylinder off and took apart n had a look and there seems to be a patch of unshiney black stuff in there. not sure if its corrosion or not. tried cleanin it off with methanol and wire wool but its not shiftin so im guessin its corrosion of some kind.
so now ive gotta find a new cylinder n hope it was that.
That will be what is left of the seal and it will be sucking air passed it.
Brake fluid is hygroscopic which means it will absorb water and in this case it looks like it has done its job.
The water condenses and makes a puddle, the oxygen content of the water produces oxidisation of the metal in the bore causing corrosion and a rough area results hence wiping the seal out.
Solution is either a good secondhand/new m/cyl or hone the old one till clean but not too hard as will become oversize.
i've lost track if it was an ebay master you are using or not but if it was ............THATS PROBABLY WHY IT WAS ON EBAY . it's a good way to get rid of your stuff that doesn't work any more. thats how a lot of ebay sellers operate
theres another master cylinder on its way so hopefully itll get it sorted. i jus gotta wait till monday for it :doubt
not an ebay item origanly mustang. i bought a load of stuff of rob for the conversion and that was in with it all.