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Discussion Starter #1
Ok, gents I'm back. After a few weeks I'm still annoyed with the front brake. One night on my way home from class my FB went soft, so I speed up my mods process by a few months. I put new pads, brake lines on the ole girl. Bleed the brakes, firm until you start riding then soft. So I took it to the deal to let the bleed the lines. Riding home...soft. Got back on here got some more advice bought my own brake bleeder, re-bleed the lines, firm sitting, ride a bit...soft. After gaining more advice used process of elimination and came to the conclusion that if my front brakes just went soft all of a sudden good chance its the FB master cylinder...purchased a new front master cylinder. Installed new MC, bleed the lines, firm sitting, start riding they get soft. Pump while riding and apply...they are firm. So I come back home and re-bleed the left side...perfect. Now the right side...not so perfect. I can not get a nice stream of fluid to come out. So my conclusion is there has got to be air in that right line.

So...is there any tips or ticks to bleeding braided lines when you now have two lines coming off of one banjo bolt? I'd hate to speed another 90.00 and go back to the dealer. I do wish I had a compressed air brake bleeder like we had at the shop I used to work at some 20 years ago. That thing was great. Fill it with fluid, add air and instantly bleed brakes.
 

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hmm , new master cylinder , 2 new lines , new banjo bolts with new crush washers . Suckin air somewhere , you sure everything is tight banjo bolt, lines into the caliper , bleed nipples ? No sign of fluid leak ? Cracked caliper ( hairline ) when it heats up expands ???? Bad caliper seals / If everywhere else is new and tight , I'd start @ the Caliper ? Just a thought......... GL
 
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Just throwing in my .02 I've seen both copper and aluminum crush washers deform when over-torqued just enough to allow some air in over time, but not enough to allow fluid out.

Aside from that tapping the lines a few times on each side can help dislodge any air bubble that might be sticking to the inside of the lines. Sometimes you have to make sure that there are no blockages on the way up too. Air rises up through the lines, but if it gets stuck inside a banjo bolt, junction block or even a master cylinder in which the bleed screw is not the highest part of the system then you have to manipulate the parts to allow the bubbles to rise. On some bikes I have had to remove the master cylinder from the perch and angle it so that the bleed screw is the highest point and then bleed the system. I've even had to crack the banjo fitting a couple times over the years to bleed air that couldn't get to the bleed screw etc. Sometimes it just takes some finesse, but I can also say that when shit like that happens it makes no difference whether you have a pneumatic pressure bleeder, vacuum pump or doing it by hand. If you have an air bubble that has its path blocked it won't move regardless of the tools you use until you free the path up of obstructions.
 

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Discussion Starter #8
DanSp1,
Yes, replaced the lever. Firm when sitting and applying the brakes soon as I'm rolling it's softer.
 

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Discussion Starter #9
Thanks for all the replies gents. Everything is as tight as I can get them without damaging any parts. I decided to remove all the fluid and rebleed the system again. Once again the left side bleed fine the rightside took putting half to 3/4 of the bottle before it looked almost as good as when the left side as in a stead stream just not the same volume as the leftside. So it's a beautiful day and once again she's sitting. I'm pretty annoyed at this point and I've learned that is the signal for me to leave it alone. I'll reattack it tomorrow with and maybe I'll see something I missed. I wiped everything down so if there is an moister I can start there. If not, guess I'll have to loosen bolts and retighten them all then bleed the system again.
 

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Discussion Starter #10
And then if none of that seems to work. Look closer at the caliper. Or take it to another dealer.
 

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Sorry for jumpin to worst case . Mikes suggestion sounds most logical . I had to bleed my under slung rear Brembo with the assembly nipple up then install
 

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Okay so if it's hard just sitting there and if you do not move the bike does it stay hard feeling if you come back after a little time? If it does not stay hard it's probably air. If it does stay hard it's probably the rotors.
 

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Sorry for jumpin to worst case . Mikes suggestion sounds most logical . I had to bleed my under slung rear Brembo with the assembly nipple up then install
Yea I had to do that to mine as well and of course many Ducati's over the years. The underslung idea has always been kinda silly to me, but I do love my Brembo calipers and cast iron rotors so it is a small price to pay...
 

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the easiest way to bleed an underslung is to reverse bleed it.

Teflon tape the bleed nipple then force fluid through it with a syringe. push it through, pull it back, push it through again, get all the air either into the reservoir or the syringe and then tighten it up. it works incredibly well and takes about 2 mins.

this method is also effective for bleeding the fronts. if you have an axial master still you likely have air trapped in the banjo. reverse bleeding will push that into the reservoir
 

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Yea I thought of that aftet🤓
 
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