Bleeding Bloody Bleeding Brakes

[DEATH_INC.]

That doesn't make any sense, if it would self bleed why wouldn't it do it without taping the lever?

Correct, and when you pull the lever in it blocks all the return holes (how would it make pressure otherwise?), so the air has no-where to go. An old wives tale.

[Laava]

One thing you could try...leave the resovoir cap loose and tape the lever hard up to the twistgrip. Leave it overnight. The theory being that air bubbles rise and it will self bleed overnight. Doesn't always work but worth a try.

Correct. This is absolutely worth doing. I had a cunt of a time, spending a couple of days, getting my GSXR750 to bleed with all new everything and was getting sick of pumping endless fluid through it.
I bled as best I could and then if I pumped the lever quickly several times it would be just short of touching the bars. I taped it back at this point and left it overnight in disgust.
Fuck me, it works! Then the brakes were awesome!

+1 to this plan. Make sure to crack the banjo's a bit too, sometimes the air gets trapped in there; messy bleed but often gets results.

Also, its not just that the piston are over retracting each time?



That doesn't make any sense, if it would self bleed why wouldn't it do it without taping the lever?

I couldn,t for the life of me work out how it could work other than all air rising to the top of the system and then burping back into the master cyl when you release the tape.
So I was pleasantly surprised. It is a very easy try as well.

Correct, and when you pull the lever in it blocks all the return holes (how would it make pressure otherwise?), so the air has no-where to go. An old wives tale.

Yip, i was saying the same thing. Hope gwigs tries it then to see how it goes for him?

[Road kill]

Buy a set of one way speed bleeding nipples.

They have a valve in them that prevents air returning through the nipple so you don't need to open/close them during bleeding.

You just crack them and then pump away until your happy all the old fluid and air has been replaced "then nip them back up again.

Google is your friend,,I'm not.

[Zedder]

Correct, and when you pull the lever in it blocks all the return holes (how would it make pressure otherwise?), so the air has no-where to go. An old wives tale.

These guys disagree: http://helperformance.com/brake-doctor/index.php?page=6

[Laava]

These guys disagree: http://helperformance.com/brake-doctor/index.php?page=6

Oh yeah, and that,s where I got the info from for my probs!
Cos I had new Hel lines.

[Drew]

These guys disagree: http://helperformance.com/brake-doctor/index.php?page=6

The reason they site for dong it, sounds like bulshit to me.

The remaining air in the system is forced out. To where? Through what?

I also want to know how someone is going to "pop the brake caliper seals", by bleeding the system backwards. Anyone care to hazard a guess, as to how many PSI of pressure there are in a brake caliper, when the brakes are pulled on hard?

I think they have typed that out in a hurry, for the masses, without too much thought going into it.

[Zedder]

The reason they site for dong it, sounds like bulshit to me.

The remaining air in the system is forced out. To where? Through what?

I also want to know how someone is going to "pop the brake caliper seals", by bleeding the system backwards. Anyone care to hazard a guess, as to how many PSI of pressure there are in a brake caliper, when the brakes are pulled on hard?

I think they have typed that out in a hurry, for the masses, without too much thought going into it.

Yeah, it seems a bit of a gloss over explanation, but from what I understand (my background is geology not engineering) the tie back gives everything time to reseat properly which doesn't happen in normal cycles of use. This process then allows the air to bleed eventually.

I don't agree with leaving the top of the master cyclinder cover off though 'cos brake fluid is quite hygroscopic.

[imdying]

Sounds like it's sucking air in.

You'd see fluid coming out the same hole.

[FJRider]

When bleeding the brakes (front or back) ... if two people do the job ... one works the levers (A child's play ??), the other works the bleed valve .. [you] ... it gets done quite quickly. Regular top-ups of the reservoir ... Done.

[Subike]

The reason they site for dong it, sounds like bulshit to me.

The remaining air in the system is forced out. To where? Through what?

I also want to know how someone is going to "pop the brake caliper seals", by bleeding the system backwards. Anyone care to hazard a guess, as to how many PSI of pressure there are in a brake caliper, when the brakes are pulled on hard?

I think they have typed that out in a hurry, for the masses, without too much thought going into it.

Fawk, Id never let you monkey with my brakes. What they are doing is allowing the air suspended in the fluid to seperate from the fliud and come to one point where it can be bled off. Air impregnated fluid can be pumped through a system for days and you will still get that spongy feel. Let it settle pettle, and harden up.

[imdying]

I also want to know how someone is going to "pop the brake caliper seals", by bleeding the system backwards. Anyone care to hazard a guess, as to how many PSI of pressure there are in a brake caliper, when the brakes are pulled on hard?

Less than a 1000psi. That document is a bit of a laugh, but worth a read.

[imdying]

Fawk, Id never let you monkey with my brakes. What they are doing is allowing the air suspended in the fluid to seperate from the fliud and come to one point where it can be bled off. Air impregnated fluid can be pumped through a system for days and you will still get that spongy feel. Let it settle pettle, and harden up.

It's rubbish. Just bleed them correctly in the first place.

[FJRider]

You'd see fluid coming out the same hole.

Only if it was downstream of the pump. An air pocket in the reservoir outlet would suck air in ... but not always the whole air bubble.

[Drew]

Fawk, Id never let you monkey with my brakes. What they are doing is allowing the air suspended in the fluid to seperate from the fliud and come to one point where it can be bled off. Air impregnated fluid can be pumped through a system for days and you will still get that spongy feel. Let it settle pettle, and harden up.

Pray then, why are they strapping the lever back? It would make no difference as to separating the air from the fluid.

I'm not offering do your brakes by the way.

[imdying]

Only if it was downstream of the pump. An air pocket in the reservoir outlet would suck air in ... but not always the whole air bubble.

lul wut... Now you're just grasping at straws.