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Discussion Starter #1
While driving through the French Alpes last week:
Used the rear brake a lot (getting out of hairpins)
2 up riding.
Slowly the rear brake pedal got soft (looks normal to me), getting warm.
Did not use the rear brake for 25km or so, to let it cool down.
First time to ride the bike at high altitude (1500 to 2300 meters.)
Got the feeling that the bike was not accelerating normal (steep road? Air intake at high altitude problem?).
- tried to find a save place to stop, bike was slowing down automatically.
- tried rear brake: rock solid
Before i found a save spot: small explosive noice and bike rolled again.

Stopped 20 meters further. Got of the bike......

See picture.
Little flames at the end of the oil line
Rear disc brake has some new colors.
The plastic for the mud guard, near the disc brake, have melted a bit.

We where able to extinguish the fire.
Tapped of the oil, cleaned the oil from the rear brake (sorry mountain water).
Wheel turns free again.

Off to the dealer next week.

My idea what happened (but would like to hear your opinion)
- rear brake heated up. Started fading a bit (soft feel in the pedal).
- due to the heat of the catalysator (just underneath the break line) the hot oil continued to warm up even more
- because of the more heat-pressure on the oil line
- pressure on the oil line slowly applied pressure to the rear brake, which heated up the brembo even more
- which in its turn heated up the oil even more - continuing circle - more and more breaking

We are happy that the rear brake did not lock up in a fast corner, and that no oil was spilled on the tyre itself.
I can accept fading of a rear brake, but not the above.



See picture. Oil line exploded


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Like driving with the parking brake on, eventually something is gonna happen!

Most people don't even know where the rear brake is simply for the fact that is useless so I would suggest to learn to ride without the help of the rears unless it's a Harley, in that case is a whole different ball game. :think:
 

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Discussion Starter #3
Except for small turning circles: you need it.
As well for very small hairpins, makes live much easier.

Just found that there is another recall for the rear brake.

Lets see if this is all going to be handled by warranty.
I expect so.




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I'm curious, has someone worked on your rear brake recently and if so, who?
 

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Sorry to hear that Martin. Hope you still got to enjoy your trip in the Alpes. Good luck resolving this. Keep us posted.
 

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i'll be here till my 85!
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quit bizar

time to put on some kevlar lines? shouldn't get that hot, No?
perhaps you tipped the pedal unwillingly?

as you said : good nothing was spilled ont the tire!

grtz
 

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Except for small turning circles: you need it.
As well for very small hairpins, makes live much easier.
I've been street riding for 30 years without using my rear brake. You don't need it. I can understand why some people like to use it in some situations, but it is certainly not a necessity, by any means.
 

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All I gotta say it you got super lucky. Especially with brake fluid not making it to the tire surface. I have to say that one of the biggest differences I noticed with getting rid of the catalytic converter is that the brake fluid did not turn black only after a couple of hundred miles like it did when I first picked up the bike (my bike got the rear brake fix 500 miles ago and had new brake fluid).
 

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Chilehead
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Sounds like the pedal wasn't adjusted properly, or the master got clogged, fluid expanded, nowhere to go, blew the fitting.

(the pedal can be adjusted so that the bleed hole is free cold, but gets blocked when hot, this is my bet) :)

The fluid can get as hot as you want, as long is the bleed hole isn't blocked, the worst that can happen is that you have no brakes! :eek:

(I have had this happen in the Alps until I learned to change my fluid every year)

If the hole is blocked, due to mis-adjustment or a clog, the heat will cause the fluid to expand, which applies the brake, which causes more heat, etc. until something goes.

I also use my rear brake, especially 2-up, in the Alps, around town, etc. In the Alps, the rear brake of my 999R gets hot enough to start squealing!

Tom
 

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Discussion Starter #10
Pedal is in the full up position. (verrryyy long travel. Will ask dealer to look at that anyway).
Also the push rod is in standard (shortest) position.

It worked in the beginning, became soft after some distance / lot of hairpins.

Left it alone, until (as described above) it started making trouble.

Stupid question: i never had the long travel/rear brAke issues on my Suzuki.
Cant the brake cylinder etc be taken from another bike? Or does it need to be Ducati?




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hi martin,
sorry to hear about your brake issue. hope it gets sorted out quickly.
there was another post very early ... (maybe lat 2010) where someone had rear pads catch fire on a freeway. not that that is of much help.

thank goodness yours didnt cause a catastrophe and you could still ride out.

cheers,
witto
 

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You mentioned you noticed a change in the characteristics of the bike, and that is when you should have investigated with a quick look over the bike. It is good that you have shown us all the impact of ignoring any warning signs indicated by the bike.

On my dirt bike on long tight single track using the rear to flick from side to side, I have heated up the fluid tremendously but although all braking temporarily disappears, it has not been as destructive as shown in your photo. I do however, use Dot 5.1 fluid which may have better components.

It is possible you had water in your brake system which turned to steam and caused such a dramatic failure.
 

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Sounds like the pedal wasn't adjusted properly, or the master got clogged, fluid expanded, nowhere to go, blew the fitting.

(the pedal can be adjusted so that the bleed hole is free cold, but gets blocked when hot, this is my bet) :)

The fluid can get as hot as you want, as long is the bleed hole isn't blocked, the worst that can happen is that you have no brakes! :eek:

(I have had this happen in the Alps until I learned to change my fluid every year)

If the hole is blocked, due to mis-adjustment or a clog, the heat will cause the fluid to expand, which applies the brake, which causes more heat, etc. until something goes.

I also use my rear brake, especially 2-up, in the Alps, around town, etc. In the Alps, the rear brake of my 999R gets hot enough to start squealing!

Tom
I sorry but this sounds like nonsense to me.
The bleed hole is for bleed maintenance only. What you are suggesting is a mechanism to guarantee brakes fail under heavy pressure.

The only possibility of pressure relief is via ABS and this is most unlikely unless the brake locked.
I suppose it could have blown seals in the pistons, but the weakest link seems to be the brake line termination.
 

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the fact that the brake line "exploded" and was on fire suggests both tremendous heat and pressure ....... im just cant see that the OP's theory fits .... maybe something really simple like the spring for the brake failing and the OP unknowingly resting on a depressed pedal :think:

anyway , it may be that we will never really know for sure ???

thankfully nothing terrible occurred , but is a lesson to stop and check whenever things dont feel right ... happens in my paranoid state every week :D
 

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Chilehead
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The bleed hole is for bleed maintenance only.
Do you mean the bleeder? :confused:

The bleed hole has nothing to do with maintenance, it is for nomal operation (what possible use would it have for maintenance? :rolleyes:)

The bleed hole is internal to the pump, it allows excess fluid (and air) to return to the reservoir after the pump is released, if this clogs then exactly what happened here can result!

The bleed hole can be blocked by an improperly adjusted free-play, or crap in the system.

My vote goes for the improper free play allowing the bleed hole to become blocked when hot.

Tom
 

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Do you mean the bleeder? :confused:

The bleed hole has nothing to do with maintenance, it is for nomal operation (what possible use would it have for maintenance? :rolleyes:)

The bleed hole is internal to the pump, it allows excess fluid (and air) to return to the reservoir after the pump is released, if this clogs then exactly what happened here can result!

The bleed hole can be blocked by an improperly adjusted free-play, or crap in the system.

My vote goes for the improper free play allowing the bleed hole to become blocked when hot.

Tom
I stand corrected as I believed the reference was to the caliper bleeder.
 

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Looking at the MTS technical manual of the ABS circuit I can see no mention of a ""bleed hole". The only pressure relief appears to be that which is applied via the inlet and outlet valves under ABS control. And unless the ABS has detected a wheel lock condition this would not apply.
 

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When you speak of pump, are you meaning the master cylinder and piston?
If you are then I believe you are referring to the compensation port and yes that can be blocked as per brake manual ... text below.

The master cylinder may also experience problems if rust or dirt plugs up the compensating or metering ports. This can sometimes create residual pressure in the system causing one or more brakes to drag. If a caliper or wheel cylinder that is in good working condition appears to be dragging, then check out this possibility.

My apologies for the misunderstanding.
 

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Discussion Starter #19
Small update

The dealer called in Ducati, they investigated together.

They are not sure yet what caused it, they will disassemble some parts further.

And investigate the cabling and ABS system (they want to exclude if possible, that the ABS had an error and applied pressure to the rear brake/did not release pressure).

They found some errors registered in the history of the computer logging, investigating if that might have a relation.

The rear brake cylinder was the latest release already.

The brake fluid: We already tapped it in the mountains, no investigation possible if there was dirt or water in it.

All damaged parts (brake parts, plastics which melted etc.) will be replaced by Ducati.

On this forum are regurarely bad samples/angry stories.
Of course I was not happy that my brake failed badly, but the dealer and Ducati (North Europe) are doing their utmost (as far as I can see/say) to investigate and solve it.

So: Very positive remarks from me on: Bruggeman Motoren, Nieuw Vennep, Netherlands and Ducati North Europe.:)

Hopefully i can pickup the bike next week. I will share what they might have found out.
 

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Good to hear Martin, I am with the same dealer, and appreciate them as well.
 
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