Ducati Monster Forum

Moto Board => Tech => Topic started by: Tenshikurai on July 21, 2008, 08:02:46 PM

Title: Brakes? Who needs them....
Post by: Tenshikurai on July 21, 2008, 08:02:46 PM
So, I seem to have a bit of trouble with the rear brakes on my bike.  The brake lever won't come back up, the rotor is scorched, and visibly warped.  The caliper is a total loss, hot enough the pistons were starting to melt and mushroom against the brake pads, and the anodizing is very discolored.

Needless to say, I need a caliper and rotor.  As to the root of the problem I'm about to tear it apart and see what I find.
Title: Re: Brakes? Who needs them....
Post by: truckinduc on July 21, 2008, 08:04:57 PM
mine has never worked. It wont return either. Im looking for a better design when i buikd my new rear sets. Good luck. Im curious to see what happened.
Title: Re: Brakes? Who needs them....
Post by: Hedgehog on July 21, 2008, 09:21:22 PM
You didn't happen to change the brake lever height sometime in the recent past, did you?
Title: Re: Brakes? Who needs them....
Post by: Tenshikurai on July 22, 2008, 07:06:25 AM
Not since August last year when I changed the brake lever.
Title: Re: Brakes? Who needs them....
Post by: Speeddog on July 22, 2008, 09:15:44 AM
Likely you had the brake adjusted such that the pushrod was too far into the master, and the piston covered over the bleed port.
This effectively seals the system.
Using the brake heats up the fluid, and it expands slightly.
This increases the pressure on the pads, so more heat.
And so it goes, until something gets hot enough or the pressure high enough that something fails.

I've got a BrakeTech iron rotor and Ferodo SinterGrip ST pads with OEM caliper and master on my S4, and it works very well.
The stock stuff can be made to work.
Title: Re: Brakes? Who needs them....
Post by: Tenshikurai on July 23, 2008, 07:40:28 AM
Hedgehog hit on the head.  I tore it apart last night, and the jamnut for the lever adjustment seems to have vibrated off, allowing the adjuster bolt to loosen up and force the brake lever down.  It must have been doing it a little at a time, as it didn't seem like the brake was dragging at all until I got up to highway speed.

So, time to check ebay for a used caliper, pick up a wave rotor, and some good pads.  I'd planned on a brake upgrade this fall, but I guess I'll do the rear half a bit early. ;-)
Title: Re: Brakes? Who needs them....
Post by: Norm on July 23, 2008, 10:36:12 AM
What's a "rear" brake?
Title: Re: Brakes? Who needs them....
Post by: He Man on July 23, 2008, 11:35:22 AM
Quote from: Norm on July 23, 2008, 10:36:12 AM
What's a "rear" brake?

its used to make a sCREEECHCHCHCHH-ing sound when your stoping hard. otherwise useless
Title: Re: Brakes? Who needs them....
Post by: Speeddog on July 23, 2008, 01:08:23 PM
Actually, they're quite useful, if you take a little bit of time to set 'em up right.  [roll]
Title: Re: Brakes? Who needs them....
Post by: canes on July 26, 2008, 09:06:29 AM
Well speeddog, I'm gonna dance with ya [evil]
Other than draining the brake fluid out of the system, how do you set up a rear brake?
Title: Re: Brakes? Who needs them....
Post by: Norm on July 26, 2008, 09:10:12 AM
Oops, my son was still logged on to my computer. It's me speeddog.
Title: Re: Brakes? Who needs them....
Post by: Jarvicious on July 27, 2008, 01:00:40 PM
Quote from: Norm on July 23, 2008, 10:36:12 AM
What's a "rear" brake?

I normally use my rear more often than the front for everyday riding.  The engine does most of the braking for me, just use the rear for little speed adjustments here and there.  The front is just for the heavy duty stopping in the twisties and such. 

Good luck with the replacement.  It's a bit disconcerting, but I often look forward to these little bike foibles as an excuse to upgrade, so enjoy!
Title: Re: Brakes? Who needs them....
Post by: DrDesmo on July 28, 2008, 07:54:02 AM
Quote from: Speeddog on July 23, 2008, 01:08:23 PM
Actually, they're quite useful, if you take a little bit of time to set 'em up right.  [roll]

Yes, what's the best way to set up for replacement rear sets to accomodate?

Thanks!

Adam