Bleeding Hints

[RIPPERTON]

Heres a cross section 3D model of a banjo fitting.
Its a Stamnas anodised alloy bolt and banjo.
Note the many nooks and crannys that air can hide in even when using speed bleeders.
Emphasizing the importance of cracking Banjos when bleeding brakes.
Note this is a prescision model detailing the imperfections in manufacture that create cavities. Even the main drilling in the bolt itself is too long.
http://i37.photobucket.com/albums/e62/ripperton_2008/Banjo-1.jpg
First loosen the banjo bolt about 10 degrees, ie crack the initial tightness then nip it up with the spanner so that it just seals the fluid in, basically a bit more than finger tight so it is easy to loosen with one hand.
Then pull the lever in as you would if you were to open a bleeder nipple, hold the lever in with one hand while you open the banjo with the spanner about 5 degrees, just enough to get the fluid (and air) to start leaking out and nip the bolt up again once the lever has bottomed. repeat till you cant get any more air out or you get a solid lever.

[Captain]

Wasn't this posted up about a month back? Mind you, good to see it again, just about to change my brake lines so the reminder is welcome :ayyy:

[Birdman]

Vacuum bleeder , never had a problem with air!!!

[unclewal]

Vacuum bleeder , never had a problem with air!!!

where can i get one? i have looked at a few auto shops and the teenage kid working there always gave me a blank stare.

[holdontight]

where can i get one? i have looked at a few auto shops and the teenage kid working there always gave me a blank stare.

Next time you go put some pants on. That should fix the blank stare.:lmao::lmao:

Auto 1 if they don't have one they can get one or Repco stores hold a lot of that tye of tool stuf.

[unclewal]

Next time you go put some pants on. That should fix the blank stare.:lmao::lmao:

Auto 1 if they don't have one they can get one or Repco stores hold a lot of that tye of tool stuf.

pfft wearing pants, what are you smoking ! If getting a speed bleeder means i need to wear pants when i go out i will go without thanks.

[tazkenny]

where can i get one? i have looked at a few auto shops and the teenage kid working there always gave me a blank stare.

I use a 20cc syringe with a piece of rubber tube attached. Works great and costs nothing.

[unclewal]

I use a 20cc syringe with a piece of rubber tube attached. Works great and costs nothing.

back flushing the system right? Might give that a try tomorrow.

[Turtle]

Never used a vacuum bleeder.......always used a twin hose bottle with a small amount of fluid in it........seems to work well....

[tazkenny]

back flushing the system right? Might give that a try tomorrow.

Haven't actaully tried that myself. I use the syringe as a vacuum bleeder.

[unclewal]

ahhh now i am with you, use the syringe to suck rather than push the fluid in. Damn good idea ! On to that tomorrow arvo i suspect.

[Dr freedom]

http://www.speedbleeder.com/

been around for a while .. used them for years myself.

[phillmac]

Repco stock the good one that hooks ap to a compressor but it is $130. Looks clean and said to work well

[studricho]

I often do a full service on older bikes including brakes and here's a few things I can add to this thread..

Bike position-

I've found the best position is the bike on the side stand with handle bars pointing hard left. This makes the master cylinder the highest point allowing air to surface.

I also will turn the handle bars to middle and right position during the bleed. I found that bikes on a center/race stand the hardest to bleed.

Caliper condition-

Old swollen rubbers in the calipers have a tiny pull back affect on the pistons if that makes sense. Trying to bleed brakes on a bike with swollen caliper pistons seals is a waste of time.

Seized slides can cause the caliper to clamp on an angle causing the piston to travel a bit further giving you the impression of air in the system.

Brake lines-

Mainly on the rear brakes, but some bikes have a loop upwards so it can trap air in it. By pushing the hose down and bleeding should get rid of this.

Master cylinder bleeding-

I often start with this first if it's a complete caliper rebuild. If the bike has rubber hoses I use fuel line clamps to clamp off the brake calipers and focus on the master cylinder. once the lever is hard then I move onto the calipers. You may need to go over the master cylinder as the air can go back up again.

Bent forks-

You would be surprised at how a slight twist can affect the clamping angle on the caliper/disc. This can cause the piston to come out on an angle and then force the caliper to conform to this angle, thus spongy feel.

Last resort-

Ever had those stubborn brakes were no matter what you do it still feels spongy?

By taping the brake lever just on over night with the bike on the stand and master cylinder at highest point it will open up the port on the master cylinder and allow air to creep up and out.

In the morning undo the tape and flick the lever about 20 times..presto hard lever.

Note. If you have replace the pads at the same time it the pads may need to bed in to get that rock hard feel again.