Ducati.org forum banner

1 - 9 of 9 Posts

·
Registered
Joined
·
124 Posts
Discussion Starter #1
I am really enjoying may new to me 2003 Ducati 999s Seems everything is in order, but have one minor thing.

I have noticed that upon stopping right before the bike comes to a halt, I have a slight pulsing in the brake lever.

The previous owner stated in his ad that the bike had "HH" brake pads on it but did not state what brand.

When taking delivery of the bike he told me about the pads and that they are hard on brake rotors but have great stopping power. Should have been a clue.

So anyway, called him back and he told me to just go over the rotors with a 180-220 grit aluminum oxide sandpaper. He told me that this is common with these pads and that the rotors are NOT warped. He said that sometimes when braking real hard and hold the brakes after stopping some pad material is left on the rotors and this causes the pulsing.Thinking the worse of course I snagged some almost new rotors off ebay and planned on putting those on.

I got nothing to lose so will give the sandpaper thing a shot. If not then will put the new rotors on.

I heard of this happening on some GS bikes but never on Ducati.

If I put the new rotors on should I also put new pads on. The pads on the bike look to have plenty of life left.

Anybody heard of this before?
 

·
Registered
Joined
·
6,787 Posts
HH pads originally meant EBC pads, but I think other brands may use those initials. You will know when you take them off, if the writing is still legible.
You may get some benefit from the sanding, which of course needs to be done carefully and evenly.
But if it doesn't work you have the other discs to try.
The way to learn what the cause was is to do one thing at a time.
The way to fix the bike quickly is to do everything.
You choose!
There is no reason why you couldn't continue using the same pads. The problem obviously stems from the rotating parts.
My approach to this issue is to set up a dial gauge on the outer edge of the disc (still on the bike, with the calipers removed) and check for run out (taking care to miss the holes). And take it from there.
And of course there is nothing to say the discs you bought are true..
As an old friend and mentor used to repeat (often) - "the dial gauge never lies".

:)
 

·
Banned
Joined
·
5,501 Posts
The bike is pretty old now, I'd put some attention onto the floating rotor buttons. They can get stuck very easily for a brief moment, which could theoretically cause a bit of wobble.

I agree with pat, you need to measure the rotors first with a caliper or dial indicator in order to determine if they're flat when cold. Then try it again after riding and see if its changed.

If you can't find any problems with the rotor, ditch the pads, put the OEM Toshiba (brembo) pads back in it and see what happens. I like the OE pads a lot, they work great for the street.

Ohh yes, I've seen this issue before with broken floating rotor pins or warped rotor.
 

·
Registered
Joined
·
1,240 Posts
HH pads originally meant EBC pads, but I think other brands may use those initials. You will know when you take them off, if the writing is still legible.
There is a two letter code mandated by the DOT, and painted on all street legal brake pads to give some indication of their ability to resist fade. Because of the wide range involved in each letter, it is only a rough indication.

A HH code brake pad material has a normal coefficient of friction of 0.55 or higher, and a hot coefficient of friction of 0.55 or higher.
 

Attachments

·
Registered
Joined
·
124 Posts
Discussion Starter #5
Will Do...

I thought my front stand would be in by now, but with the holiday it will be next week. New Rotors will be in too. I am going to take the front wheel off and put it on my stand. I will check run-out on the rotor and rim. If that is good then I will lightly sand the rotors AND check the rotor carriers to make sure they still "float" as they should. Then put them back on the bike and see where I am. May just go on and put the new rotors on and clean the old ones. Never know when you need some spare rotors.


What causes the material build up is hard braking and then holding the brakes on the hot rotor. Some of the pad material then comes off and sticks to the rotor. Several of my BMW friends have had this happen on some GSs in the past.

Against my better judgement I am going to stick with the pads that are on the bike. They just have too much life left in them.
 

·
Registered
Joined
·
12 Posts
Onesaintsfan, give tyes suggestion of the rotor buttons a look. You just need a suitable size bolt, a wingnut, and two washers large enough to grip the button (or bobbins). Thread the nut through then tighten the wingnut until the washers grip and button and they rotate slightly. My bike had the same symptoms until I did the above procedure and found a number of the 'buttons' were seized. A quick twist if all of them and the pulsing disappeared.
 

·
Registered
Joined
·
12 Posts
DId not think about the wing nut. Will do
In my opinion (& experience on my old 749) it's worth a try as takes 10mins and you don't need the wheel removed, bike on a stand, any tools etc etc. just the nut, bolt and two washers.

Worst case you spend 10mins to remove this from the equation.
 

·
Registered
Joined
·
124 Posts
Discussion Starter #9
Success !

:dance:I did not remove the wheel and use the gauge just decided to give it a shot with the wheel still on the bike. Lightly sanded both sides of the rotors. Then checked each carrier and they were all free. then cleaned everything up with brake cleaner.

All is good now. All pulsing is gone.

I am about to spoon on new Michelin PP 2CTs and am going to put my new rotors on anyway, but will certainly hold onto these as spares.
 
1 - 9 of 9 Posts
Top