Easy brake Bleeding

[kiwi60]

I've just finished a total rebuild of both front brake calipers following the binding problem at the last race meeting.

I've replaced the braided brake lines with new plastic coated braided lines, new oil and dust seals, new olives on the lines, and new sealing washers, but have re-used the fittings as they were perfect.

In addtion I fitted a late model Suzuki GSF1200 master cylinder 3 weeks ago, which works perfectly.

The only thing left to do was bleed the system.
Bleeding brakes is not one of my favorite jobs. Over the years I've invested in a Sykes Pickavant brake bleeder, which has never really worked right, or used the monotonous pump / open bleed nipple / close brake nipple / pump etc etc etc
However I discovered an extremely quick, effective way to bleed the brakes, and guarantee that there are no air bubbles in the lines.

First, get a new bottle of 5.1 brake fluid (I always use Motul), and - heres the important part - a 1200mm long length of clear tubing that is a nice snug fit over the bleed nipple.

Right then, take the top off the brake resovoir, open your nice new bottle of brake fluid and fit one end of the tube over the nipple. Next, thread the remaining tube up to the handle bars with the end near the resovoir (a cable tie to hold it to the upper fairing stay works a treat.
Start bleeding the brakes in the normal way - a few strokes on the lever then a slow stroke as you crack the nipple open a bit to let the air through. After there's about 150mm of brake fluid in the tube, I didn't have to keep opening and closing the nipple any more.
Carry this on until the brake fluid is almost to the top of the clear tube (being careful not to let the resovoir pump dry), and then a few more pumps of the lever to get the fluid to the end of the hose and then put the end of the hose into the top of the open resovior.

What you now have is continous bleeding as air cannot enter the tube because it is under the surface if the fluid level.
You can now open the bleed nipple and pump away for several minutes - you'll be surprised how long the air bubbles take to get all out.

I did this on both sides with a 100% drained front brake system and had them fully bled in 17 minutes - usually I'm swearing at it for at least a hour or so.

Just one note of caution - make sure everything is completely clean - you don't want any dirt in there eh.

And the cost of the hose - about $1.50.

[davemfox2]

Nice one mate; I think that's the best description I've seen in a long time

I thought I was the only one who had problems with those Sykes units as the majority of people I know with one never seem to have an issue!

Dave

[ThomVis]

I had to look up the Sykes Pickavant brake bleeder, doesn't look that high-tech, just a catch can.
I'm using a vacuum operated bleeder found on Ebay. You put the hose on the bleed nipple, apply air-pressure, open the nipple and watch the fluid drain from the reservoir, topping it up before it reaches the bottom. As a final touch I let the system sit overnight and do the "pump / open bleed nipple / close bleed nipple / pump" routine to finish it off.
Another discussion was that this procedure allows air in trough the threads of the bleed nipple, but a dot of copper-paste on the outer threads will solve that.

[Fatdog]

I had to look up the Sykes Pickavant brake bleeder, doesn't look that high-tech, just a catch can.
I'm using a vacuum operated bleeder found on Ebay. You put the hose on the bleed nipple, apply air-pressure, open the nipple and watch the fluid drain from the reservoir, topping it up before it reaches the bottom. As a final touch I let the system sit overnight and do the "pump / open bleed nipple / close bleed nipple / pump" routine to finish it off.
Another discussion was that this procedure allows air in trough the threads of the bleed nipple, but a dot of copper-paste on the outer threads will solve that.

Using PTFE tape on the bleed nipple threads will also prevent air from getting in.
After bleeding the brakes or clutch I always apply the brake/clutch lever and clamp it to the handlebars with a rubber band (so that the system is under pressure).
Leave it 24 hours for it to force any air out of the system and you should get a firm feel at the lever.

[kiwi60]

One of the other racers had a vacuum bleeder at the track the other week which he paid about $50 for, it looked ok, but to be honest, they just don't compare with $1.50 of clear tube for time efficient bleeding.
As for waiting 24 hours to force the air out of the system - no thanks, a completely bled system in under 20 minutes - especially with a deadline to meet with race meeting coming up makes me feel a lot happier - but, each to their own

[Fatdog]

The 24 hour thing is only a double check that I do once I have blead the system in the standard way.
By putting the system under constant presure it will always force air (if any present) out of the brake line.
Generally I only leave it overnight anyway as I don't tend to us the bike when asleep.

[Tiger]

Cheers Kiwi

I have a POS VF1000 Honda in the shed that despite new braided lines and M/Cyl kit still has air [it pumps up a little].

Well done that man.

PS. I anyone in Oz wants to buy a VF1000F2F in good condition PM me, it is a barge after my old 650 Triumph and I have fallen in love with the FZR1K.