Fitted Braided Hoses - Bleed problem

JohnD · Post by **JohnD** » Tue Apr 10, 2012 4:48 pm

Hello

As the title suggests, I have just fitted a braided goodridge race front brake setup on the SP1.... which all went swimmingly to begin with until I started bleeding the new brake fluid through!

Using a vacuum bleeder, I bleed the left caliper first, which worked out fine. Onto the right caliper, and it's proving a REAL pain.... it just keeps pulling loads of air bubbles though continuously which don't let up. Have tried it a couple of times now on two separate occasions, and still no change! Also have quite a few bubbles coming up through the reservoir when pumping the brake lever. Even though the lever feels firm enough and the brakes work fine, I'm in no way happy with it.... where are all these bloody air bubbles coming from arghhhh!?!?

Am away til the weekend, but was thinking of getting myself a syringe and reverse bleeding the right caliper when I get back. Do you think this will work? Am starting to lose patience with it now.... but you gotta be sure with dem brakes eh!

Any help much appreciated.

regards

John

benny hedges · Post by **benny hedges** » Tue Apr 10, 2012 5:27 pm

undo the calipers and let them hang down overnight with lever taped to the bar.
works for me.

be patient.

there'll be loads of tiny bubbles and if u leave it overnight they form one big one. makes it easier to bleed.

when i change the fluid i take the nipple completely out and feed new fluid in til it runs through clear, then fit the nipple and bleed as normal.
it can take a while. just take your time.

tony.mon · Post by **tony.mon** » Tue Apr 10, 2012 8:07 pm

You may have a slight leak on the bleed nipple thread.
If you can get bubbles out with the vac syringe when not pumping the lever and all connections and nipples tight; that's the problem.
Could just be a bit of grit on the seat, try a strip and clean, if that doesn't work, new bleed nipples.

JohnD · Post by **JohnD** » Sun Apr 15, 2012 10:15 am

That's an excellent suggestion tony... I'm gonna investigate ASAP!

Thanks mate!

John

gilson · Post by **gilson** » Sun Apr 15, 2012 11:36 am

I use a mityvac and they cause this problem when you give it too much vacuum. The air is being sucked in at bleed nipple area between the tube and nipple. It happened to me until I realised what I was doing wrong.

Only give the vacuum pump a few squeezes. This will pull the fluid through. When the fluid is changed, tighten it all back up. Then squeeze the lever to raise pressure and open each nipple in turn expelling only enough fluid for the lever to touch the bar. Obviously tighten up the nipple before letting the lever return.

Do this for the banjo bolt at the lever too.

Another lesson I learnt is that when you are testing the brake lever's feel, it will ALWAYS seem soft when at a standstill. Ride it and you'll never put that much pressure on the lever.

Good luck

JohnD · Post by **JohnD** » Mon Apr 16, 2012 1:21 pm

Started the whole thing again using the 'traditional' method, and no problems at all! Lever is as firm as you like and brakes are now awesome!

It seems that the vacuum bleeder was creating problems that weren't actually there (i.e. sucking air in around the tube and nipple like gilson suggested)!

It's ironic really, as I thought i'd treat myself this time round and bought the vacuum bleeder to make the job easier.... turned out to be more trouble than it's worth! So save your money folks and keep it simple!

Thanks for your help folks.

cheers
John

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