Page 1 of 1

Cleaning Contaminated Rotors

Posted: Tue Aug 20, 2019 2:47 pm
by gwilson
Hi All,
I made a mistake last week washing my road disc bike and ended up getting bike cleaner on my rear disc rotor. Unsurpisingly when I went out and rode yesterday the braking power was reduced and it was loud. My pad was nearing the end of its life so I'm just going to replace it, but I can't manage to clean the blackish/oily residue off the rotor where the pads touch. In the past I've always used rubbing alcohol on paper towel to clean the rotor, but it doesn't seem to be doing much. Does anyone have any suggestions of how I can properly clean it? They're Ultegra 8070 brakes and RT800 if that makes a difference.

Cleaning Contaminated Rotors

Posted: Tue Aug 20, 2019 2:47 pm
by Weenie

Re: Cleaning Contaminated Rotors

Posted: Tue Aug 20, 2019 3:06 pm
by Attermann
just some sandpaper, works like a charm.

Re: Cleaning Contaminated Rotors

Posted: Tue Aug 20, 2019 3:32 pm
by gwilson
Attermann wrote:
Tue Aug 20, 2019 3:06 pm
just some sandpaper, works like a charm.
On the rotor itself? I've read people using it on the pad before, but not the rotor. Is there a certain kind of sandpaper you'd recommend?

Re: Cleaning Contaminated Rotors

Posted: Tue Aug 20, 2019 4:19 pm
by kode54
i clean with either brake cleaner if really dirty or wipe down with isopropl alcohol.

Re: Cleaning Contaminated Rotors

Posted: Tue Aug 20, 2019 5:22 pm
by Hexsense
rubbing alcohol first then Acetone or brake cleaner or White Lightning Clean Streak.
I've never really use pure Acetone though, more likely just go directly to White Lightning Clean Streak.

* There are multiple type of brake cleaner, some are weak, but also some are simply Acetone + Heptane, which will be more effective than pure acetone.

Re: Cleaning Contaminated Rotors

Posted: Tue Aug 20, 2019 6:17 pm
by mattr
Don't use automotive brake cleaner unless it's oil free. (Many brands contain a light oil to protect the disc from surface corrosion, auto brakes get hot enough, quick enough to burn it off.)

Electrical contact cleaner does a similar job and is almost always oil free.

Re: Cleaning Contaminated Rotors

Posted: Tue Aug 20, 2019 6:57 pm
by moyboy
Acetone worked for me, do it until the rag is clean.....

Re: Cleaning Contaminated Rotors

Posted: Wed Aug 21, 2019 2:54 am
by Schadenfreude
gwilson wrote:
Tue Aug 20, 2019 3:32 pm
Attermann wrote:
Tue Aug 20, 2019 3:06 pm
just some sandpaper, works like a charm.
On the rotor itself? I've read people using it on the pad before, but not the rotor. Is there a certain kind of sandpaper you'd recommend?
80-120 grit wet and dry sandpaper. I had howling disc brakes recently. New pads and sanding of the rotors, followed by 30 mins of bedding in the pads, seems to have solved the issue. I'm pretty sure I've read that you should sand the rotors after putting in new brake pads - I could be wrong though.

Re: Cleaning Contaminated Rotors

Posted: Wed Aug 21, 2019 4:29 am
by TobinHatesYou
Clean Streak or the Finish Line yellow can...basically the same thing. You’ll need to bed your rotors / pads in again.

Re: Cleaning Contaminated Rotors

Posted: Wed Aug 21, 2019 5:52 am
by icantaffordcycling
"Squeal out" is a really good rotor resurfacing product.

Re: Cleaning Contaminated Rotors

Posted: Wed Aug 21, 2019 5:52 am
by Weenie

Re: Cleaning Contaminated Rotors

Posted: Wed Aug 21, 2019 6:51 pm
by none
This is what I use, even on cars & motorcycles.
Safe to use on brake pads, too.
Image