Lt_Scallywag

As the title says, do you guys get this weird silvery stuff all over your pads after a few rides? My pads last about 1.5 weeks before I have to clean them off. Braking performance decreases by about 10x as well. I have provided before cleaning, and after cleaning pictures.

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Tartybikes: " The interestingly named 'Lt_Scallywag' "

literocola

WTF

Sam.S

Yup I would notice it when I take my wheel off.

But it doesn't affect the performance. Whatever the problem, it's not it.

treewizzard

my brake pads on my bikes that use rim brakes always get pieces of metal stuck in them. i have never seen a pad that dirty before.

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Lt_Scallywag

This is definitely the problem. After I washed the pads and reinstalled, braking performance was back up. I have no idea where all of it is coming from. It is hard to imagine that the aluminum on the rim is rubbing off that much.

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Tartybikes: " The interestingly named 'Lt_Scallywag' "

xsv4crob

That's crazy. Grind? Worn or new? Tar? Do you ride in wet conditions? What kind of rim are you running?

SmartBoy

Might just be aluminum oxide. All raw aluminum will shed this stuff. Go handle some raw aluminum plates for a couple of hours and your hands will come away black.

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Lt_Scallywag

Running a Trialtech sl rim with a grind, and Trialtech pads in TNN backings. I ride in completely dry conditions as well.

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Tartybikes: " The interestingly named 'Lt_Scallywag' "

xsv4crob

Can you see any rubbing of the TNN backings on your calipers? Unless that's happening to produce all the dust, or the grind is really worn and there's a lot of brake dragging going on, I'm at a loss here. Anyone know of that rim being especially soft?

Lt_Scallywag

There is no wear on the backing and I never drag my brake. It is a bit dusty in North Dakota, but last time I checked dust was not silver...

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Tartybikes: " The interestingly named 'Lt_Scallywag' "

xsv4crob

In that case, like literocola said: "WTF"

I'm curious to find out the cause....

dark_biker

My old Koxx browns used to look like that but still work really well. It has to be worn off aluminium oxide off the rim, is that a fresh grind you're running? Or is it really dead?

twolfe

Mine were looking exactly like that and I was running an old grind. I have since been putting fresh grinds on and they are fine.

AndyT

You ride by the beach yes? Perhaps salt water/sand in the air is getting between your pads and making some kind of gnarly sand papery substance that kills your pads...

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SHENRY86

I get the same thing on my tnn's, not sure but i think its the alum. from the rim as others have mentioned and cleaning it off certainly helps. What have you been using to clean your pads?

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Ross W.

I get that from time to time. It usually is from some sort of contamination on the rim. I do ride in dusty conditions a lot of the time too, although I'm not sure if that has anything to do with it. Mine usually start to look like that when my slaves are leaking, or I didn't clean them off well enough after bleeding.

Check the slave cylinders and brake lines around the rim very carefully for brake fluid. Is there any fluid on the back of the pads? If you sand the pads and put a fresh grind on the rim to get rid of any contaminants, it should improve. If it continues to happen, something is getting on your rim somehow.

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Webcyclery - Echo, Rockman, Inspired, TNN, Trialtech

Hydro Flask

Lt_Scallywag

Performance definitely increases once I clean the pads , and even more with a new grind. There is occasionally water on the back of the pads, but I dont know if it is from the slaves leaking or environmental conditions. The condition usually only appears once my grind gets a bit worn. To the person 2 posts above, I just rinse the pads with warm water and then rub them on some carpet.

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Tartybikes: " The interestingly named 'Lt_Scallywag' "

SHENRY86

there is some regular fluid on the back of the pad backing and lots of dust buildup around the slave cylinder but no apparent large leak. . . could that be a bad seal?

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xsv4crob

The strange thing though is that it's on both pads (both sides) pretty evenly. I think this reduces probability that it's a leak but instead may be more due to environmental factors.

How often are you having to grind?

eaterofdog

Yeah I was getting black gunk when I rode maggies.

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Muerto

My guess is gunk from the rim. Either dust or oxide, or both.

I get it too. And so do all the people I ride with.

RobbyBobby

I get it on my pads after a few weeks. I just rub em over a file to get down to the fresh rubber.

Ross W.

Could be a bad seal. My slaves are fairly old and leak a tiny bit normally, so I usually have a little bit of dust buildup around the cylinders. Ideally, there should be no leakage or dust buildup at all, but if the brakes are old or if you have Echos, then it's fairly normal to see.

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Webcyclery - Echo, Rockman, Inspired, TNN, Trialtech

Hydro Flask

SHENRY86

they are 2011 HS33's so they are not very old, just built this bike up in february so they only have about 2 months on them. I have seen the dust and fluid on the back of the pad, its pretty minimal, but it is there. . . normally I just wipe it down and be on my way. dosnt seem to be any play in the lever or a noticable loss of pressure.

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Caesbiketrial

I get thart all the time when i ride in dusty conditions... i can know how clean my pads are watching the dust in my rims, tar also get the problem worse it sticks all the shit on my rims and my tnns padas its not a problem but will be better if i clean and get a fresh grind... dust and tar is a bad combination