View Full Version : Zx12R brake bleeding hell! Help!
I've changed the seals on the front pair of calipers, and have spent far too long trying and failing to firm them up.
I'm lost as to what else to try?
Any suggestions most appreciated....
wind welder
08-04-09, 20:50
I've changed the seals on the front pair of calipers, and have spent far too long trying and failing to firm them up.
I'm lost as to what else to try?
Any suggestions most appreciated....
Hi,
Get hold of 2 big syringes, fill 1 with new brake fluid, put it on the brake nipple and push the fluid back to the reservoir,along with any air bubbles, use the second to empty the reservoir as it is filled.
That's how we used to do it on troublesome systems.
Hope it sorts it.
Cheers Trev.
wots upwith them at the mo? Bit spongy, absolutely no pressure?
I had a drama with my 6 at the back end of last year, no pressure pumping like mad for ages! Anyway, I would not recommend it unless you are brave or stupid, in my case I proved just plain stupid - put me pipe on the nipple and tried to suck like mad (if ya'v got a filthy mind that don't sound very pc does it?). Work eventuallyto start get the fluid thro' but it tasted like hell and burns quite a bit!!!
A nice mate of mine then let me know he had one of those hand held vacuum bleeding things that he reckons would have sorted it in no time.
If ya just havin probs gettin all the air bubbles out, tie the brake lever against the clip on and leave it over night, should force the air to the top of the system.
Hi,
Get hold of 2 big syringes, fill 1 with new brake fluid, put it on the brake nipple and push the fluid back to the reservoir,along with any air bubbles, use the second to empty the reservoir as it is filled.
That's how we used to do it on troublesome systems.
Hope it sorts it.
Cheers Trev.
Thats a gleeming idea Trev, wish I'd have heard of that one before, but I certainly remember it, instead of my last moment of stupidity!!!
team french
08-04-09, 21:31
if bleeding, start at the top and just crack open the banjo at the master cylinder(with nessicary protection around!!!) few pumps then nip. then move down the line to spliter/caliper banjo's etc then nipples. if still no joy id be thinking about brake hose condition or new master cylinder piston/seals.
I've sucked it through with a vacuum pump;
I've pushed the fluid up from the bleed nipple;
I've circulated the fluid with hose ends in the reservoir;
I've heated the calipers up to move the bubbles;
I've checked the banjos for air pockets;
I've pressed the lever 'on' each night......
I've used 2 litres of fluid?
I have no leaks?
I have no pressure worth talking about?
I'm at a loss?
Only the master piston seals to check - but they were alright before?
team french
08-04-09, 21:38
id look for a new master cylinder or at best a seal kit for it. probly ok to push fluid tru when little resistance but may be going around the piston seals when system is closed. ive had this before but on an older bike.
Al
I've had this on a set of 6pots, take the callipers off and string them up as high as you can with a piece of plate (or something like a spanner) in between the pads, now do your bleed again - the piston in the master cylinders are so small they sometimes can not shift the amount of air out - let gravity help you !!!
If this still don't work, then you need a master cylinder repair kit as the seal will have gone/perished.
Hope this helps.
Jim
Soft But Happy
08-04-09, 23:23
having no idea on motor bikes there is only one thing left in my book
HIT IT with a big hammer :D
I've sucked it through with a vacuum pump;
I've pushed the fluid up from the bleed nipple;
I've circulated the fluid with hose ends in the reservoir;
I've heated the calipers up to move the bubbles;
I've checked the banjos for air pockets;
I've pressed the lever 'on' each night......
I've used 2 litres of fluid?
I have no leaks?
I have no pressure worth talking about?
I'm at a loss?
Only the master piston seals to check - but they were alright before?
You are filling the correct reservior and using the brake lever on the right and not the clutch lever on the left arnt you.
LOL:LOL:LOL: Good one .... that thought did go through my mind, but thought I would refrain from that one.
Its a bit like when I got half way through stripping my monkey bike engine to see why it wouldn't go, then my lad (2yrs old at the time) came in and started flicking the kill switch :eek::eek::eek:
Penny dropped .... Kids eh, ya just got to love em :D
No need to worry about any of that 'amateur' shinanigans with my workshop antics!;)
Anyway - the clutch is a cable on this bad boy. But your consideration is much appreciated!I:
Although jimbo, I wasa late to work a few years ago, because of the same kill switch error. I thought it was the alarm/immobiliser and 3 hours later the pennt dropped!:(
I've ordered the master kit - hopfully that it sorted.
I also ordered paint from RS Paint to finish a pannel I damaged when I dropped it on the driveway. It turns out that the Kwak paint is a 3 pack candy colour affair. Expense to buy, and an ache to apply.
Why is this sooooooo hard? WHo/what did I do wrong to?
yeah sound like your master seals have gone, when you have replace them, best way to get a good brake is to do half pulls on the lever to pump the fluid round rather than all the way back tothe bar:)
tom
No need to worry about any of that 'amateur' shinanigans with my workshop antics!;)
Anyway - the clutch is a cable on this bad boy. But your consideration is much appreciated!I:
Although jimbo, I wasa late to work a few years ago, because of the same kill switch error. I thought it was the alarm/immobiliser and 3 hours later the pennt dropped!:(
I've ordered the master kit - hopfully that it sorted.
I also ordered paint from RS Paint to finish a pannel I damaged when I dropped it on the driveway. It turns out that the Kwak paint is a 3 pack candy colour affair. Expense to buy, and an ache to apply.
Why is this sooooooo hard? WHo/what did I do wrong to?
I was only kidding about the clutch ;)
Im having a nightmare at the moment, I have a 14 and a ZX9 track bike. Up at Cadewll on Monday I lost 3rd and 4th gears so bike is in bits but cannot undo the front sprocket bolt, it isnt going to budge at all.
Once it is off Ill remove the engine and split the g/box,I have all the cogs to go on as the splines on the shaft I got are mangled, it looks like some monkey has had it in a vice :(
There is nothing easy, but thats what keeps us on our toes :D
I have tried this tested formula before and its a winner, undo your master cylinder banjo bolt and bleed new fluid thru..it does go a bit all over the place so plent y of rags! once you have given a few pumps through lock the banjo bolt off....I trust you have a jar with the bleed nipple rubber bleed pipes submerged....? bleed the brakes as normal one calliper at a time..you will see the bubbles coming out into the jar this will be all the air....coming out....you shaould have a feel of preasure soon..Brent