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Discussion Starter · #1 ·
I am sorry to be posting yet another pissed off post, I realise that all of you are enthusiasts whereas I seem involved in a love hate relationship with Ducati. I had a drop today, low speed and caused by losing both brakes in a hill start. The symptoms are sort of like air in the lines but different because there is not air in them. Rear brake....pedal soft and when cold only what I can describe as a squishing noise from master cylinder. Pumping does not firm up brake. One month, 800 km ago dealer replaced fluid which was dark. Now fluid darkening. Front brake ok under gentle braking but if constant pressure on brake lever applied handle goes to stop. My, non engineering personal opinion is that seals in both cylinders are bypassing fluid under pressure. Any other ideas most appreciated.
 

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Speaking for myself. Enthusiast… Maybe. But there's still no justification for what you seem to be experiencing. I can imagine I'd very soon go off Ducati if I was having a similar run. Sorry, that's not a very productive post to address your problem mate. I'm sure the tech-heads will be along soon ;)
 

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Discussion Starter · #3 ·
Speaking for myself. Enthusiast… Maybe. But there's still no justification for what you seem to be experiencing. I can imagine I'd very soon go off Ducati if I was having a similar run. Sorry, that's not a very productive post to address your problem mate. I'm sure the tech-heads will be along soon ;)
Thanks for the reply. I have just read up on the Brembo recall. The symptom matches.....fluid leaking past the piston. Only the cafe racer was in the recall and mine is a sled.
 

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Discussion Starter · #5 ·
You could need to bleed the abs module aswell. If you’re not seeing any fluid leaking then it’s probably not leaking.
Yes that is quite possible but there is no nipple on the ABS. I had thought that the brake cylinder was surrounded by a return jacket so if the seals leaked fluid would still not escape...is that correct?
 

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I’m no expert but I’ve owned many vehicles with leaky master or slave cylinders and you usually can see a leak or a weep around rubber boots. Try pull any rubbers out the way to inspect. I don’t think you bleed the abs module like you think. You have to loosen the connections to it and bleed it like you would the caliper (loosening and tightening while compressing the lever) Wrap a rag around the connector to catch the oil coming out and watch for the bubbles to stop
 

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Also, just reread your original post and the darkened oil may suggest bad calliper seals but find that hard to believe on both the front and rear. Because both brakes are failing it suggests somewhere where they are both connected, e.g. the abs module.
 

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Discussion Starter · #8 ·
Also, just reread your original post and the darkened oil may suggest bad calliper seals but find that hard to believe on both the front and rear. Because both brakes are failing it suggests somewhere where they are both connected, e.g. the abs module.
I have to agree. But it is a new bike so simply the wrong grade or contaminated brake fluid at commisioning would do it too. So far I have been unable to brake hard enough to activate the ABS. There was also the Brembo piston recall but that only impacted the cafe racer. Two finger pressure on the front handle is enough to bring it to the stop,
 

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Cant blame Ducati unless the brakes say Ducati which they dont. Call Brembo first thing with part #'s. To me it sounds like bad internal seals or o-rings. Had the same happen on a new pair of MTB brakes. Had the calipers rebuilt (under warranty) where they replaced all internal seals and that fixed the problem even though there never was a leak. Sometimes brakes are assembled on a friday afternoon and an o-ring or seal is not set properly.
 

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Discussion Starter · #10 ·
Cant blame Ducati unless the brakes say Ducati which they dont. Call Brembo first thing with part #'s. To me it sounds like bad internal seals or o-rings. Had the same happen on a new pair of MTB brakes. Had the calipers rebuilt (under warranty) where they replaced all internal seals and that fixed the problem even though there never was a leak. Sometimes brakes are assembled on a friday afternoon and an o-ring or seal is not set properly.
Are the master cylinders Brembo too?
 

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Discussion Starter · #12 ·
I have no idea who makes the MC. But I do have a good idea that you have a faulty o-ring or seal. Especially if your fluid turns dirty so quick and you have reduced braking performance.
I couldn't agree more but whereas the slave cylinders are obviously Brembo I am not at all sure about the masters.
 

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Just looked at the recall and it has to do with replacing a plastic piston with an aluminium piston. Have that checked. Good news is the replacment seal kit for the floating piston is cheap. But first thing I would do is call brembo with your MC part # and ride it gently straight to the dealer, safer to haul it, and get it sorted ASAP.
 

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Discussion Starter · #14 ·
Well bike now with dealer. I showed them the lever travel and their first reaction was 'that's normal' here it is what do you think?
 

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how can they say the lever pulling to the bar is normal! Haha

but for both brakes to have faulty parts is pretty unlikely. I still think it’s got to be something to do with air somewhere
 

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Whoever at that dealership said "oh that's normal" needs to have their head examined. If you're up to it, bleeding brakes yourself isn't a terrible job.
 

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I am sorry to be posting yet another pissed off post, I realise that all of you are enthusiasts whereas I seem involved in a love hate relationship with Ducati. I had a drop today, low speed and caused by losing both brakes in a hill start. The symptoms are sort of like air in the lines but different because there is not air in them. Rear brake....pedal soft and when cold only what I can describe as a squishing noise from master cylinder. Pumping does not firm up brake. One month, 800 km ago dealer replaced fluid which was dark. Now fluid darkening. Front brake ok under gentle braking but if constant pressure on brake lever applied handle goes to stop. My, non engineering personal opinion is that seals in both cylinders are bypassing fluid under pressure. Any other ideas most appreciated.
Reminds me of an issue I had on my Mountain Bike years ago. No leaking, but would lose pressure. Could pump it and would firm up, but then start getting soft again right away. Turned out to be the piston in the front brake lever. Changed all internals in brake lever and new break fluid. Does not take to long for brake fluid to break down. Heat or faulty parts...BOTH YOUR BRAKES...? MAYBE BOTH BRAKES WERE MADE AND ASSEMBLED AT THE SAME TIME..? SAME BATCH OF FAULTY PART'S..? IT HAPPENS.
 
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