High pitched sound from rear brakes

[pannayar]

Got new rear brake pads installed yesterday. Today, I got a swingarm rear stand. It has been some years since I used one... so the very first time I goofed up a bit doing it alone (the bike was not rested evenly on both sides), and when taking the stand off, one side came off first and the other side was on the stand for a very brief period... Later I cleaned the rims, chain, lubed it.. .went for a ride to notice a high pitched sound whenever the rear brakes are applied. Any thoughts on the cause, fix? Thanks.

 

[mototireguy]

Squeaky brake pads, because squeaky brake pads happen.

Which brand/model of brake pads did you install?

 

[Tri750]

Since you got the pads installed the day before, you would have noticed a problem sooner I think.
Saying that, new pads should be bedded in per the package instructions.
Since you lubed the chain, it's very possible you got some chain lube spooge on your rotor. That would give you a noise and maybe a bit less rear brake effectiveness.
Without looking at it, very hard to say.
You could use your new stand again and some paper towels and brake cleaner to clean the rotor. Isopropyl alcohol will work to save some $. If the noise changes you're on the right track. The shade tree method after that is to ride the bike and drag the brake to clean it off.
Maybe have a second set of eyes give a look?

 

[ALANRIDER7]

Have it inspected by someone with a sharp eye.

 

[pannayar]

Which brand/model of brake pads did you install?

EBC HH

Since you got the pads installed the day before, you would have noticed a problem sooner I think.
Saying that, new pads should be bedded in per the package instructions.
Since you lubed the chain, it's very possible you got some chain lube spooge on your rotor. That would give you a noise and maybe a bit less rear brake effectiveness. Without looking at it, very hard to say. You could use your new stand again and some paper towels and brake cleaner to clean the rotor. Isopropyl alcohol will work to save some $. If the noise changes you're on the right track. The shade tree method after that is to ride the bike and drag the brake to clean it off. Maybe have a second set of eyes give a look?

Yeah I do not remember any squeal on the same day. It was after this swingarm stand event. So I was/am inclined to think if a partial weight of the bike on one side of the swingarm could cause any minute misalignment b/w the pads and the disc... but I am told such a thing is quite unlikely. Also the lube being the culprit is not likely since the small ride I went was before lubing (rode to get the chain warm before applying the lube). I will try cleaning the rotor (you mean the disc, right?) when I get home today. Alcohol/WD40/Kerosene... which one is better?

Have it inspected by someone with a sharp eye.

I got it inspected at Evolution (that is where I got the pads installed). Diagnosed with nothing unusual. The tech told me the brakes feel 'good and strong'. To me, the squeal is still there, but probably not as much as yesterday. May be the pads need to "bed in". I was told give it a week or two (while using the rears a bit more) and see if it still persists...

 

[ST Guy]

Good lord, man......WD40?? kerosene?? Those will will lubricate the hell out of your brakes.

If you've got some rubbing alcohol around, try that first. And use an absolutely and totally clean rag. Do NOT put the bike up on a stand and idle the engine in gear when doing this. Slow hand work only.

If the alcohol won't do the trick (and it might not, depending upon the contaminant), get yourself down to your local auto supply store and get some brake cleaner, usually in a spray can. And don't spray your rotor, spray the rag and then wipe it down thoroughly. Repeat multiple times.

And you might consider removing the pads and wiping them down as well.

 

[Tri750]

where do you even buy kerosene anyway?
I like those blue paper towels. but a clean towel from the linen closet will work just fine.

 

[pannayar]

where do you even buy kerosene anyway?

OSH

 

[splat]

Pannayar:

PLEASE PLEASE PLEASE strongly consider what I sent in the PM. You are gonna fucking kill yourself if you don't, which may or maynot be a big deal. But you might kill innocent children crossing the street or a family on their way to church, a bride on her way to her wedding.

Come on, man! WD40 on your rotors? Seriously?

 

[pannayar]

PLEASE strongly consider what I sent in the PM. You are gonna fucking kill yourself if you don't, which may or maynot be a big deal. But you might kill innocent children crossing the street or a family on their way to church, a bride on her way to her weddings

Did you not read or understand my pm reply? You do care too much. Have you considered becoming a priest?

 

[splat]

I have, but I realized that i don't really like boys.

But to be honest, try a little gear oil on your rotors. Front and back. It helps with anything squeaky, including hinges. Make sue it's gear oil though, if it's normal oil it'll fling. Just a light layer, maybe apply some with your fingers .









/sarcasm

 

[pannayar]

gear oil?

 

[Wicked4Racin]

WTF, gear oil on brakes.... Iv never tryed that and WILL NEVER USE OIL ON MY BRAKES! anyways, when oil gets on your freshly new pads and ruins them what are you going to do?

 

[mototireguy]

Thread decay into the realm of sarcasm.

 

[OldFatGuy]

Got new rear brake pads installed yesterday. Today, I got a swingarm rear stand. It has been some years since I used one... so the very first time I goofed up a bit doing it alone (the bike was not rested evenly on both sides), and when taking the stand off, one side came off first and the other side was on the stand for a very brief period... Later I cleaned the rims, chain, lubed it.. .went for a ride to notice a high pitched sound whenever the rear brakes are applied. Any thoughts on the cause, fix? Thanks.

Like they told you at Evolution, give the brakes a week or so to bed in. Even then, the sound may not go away. Brake squeal is pretty common, depending on pad compound. Cheap organic pads tend to be pretty quiet, but they don't usually work as well.

Have it inspected by someone with a sharp eye.

Like this guy:

Oh, wait. I may have misread that...

 

[Wicked4Racin]

make sure the pads are also bled properly, both pucks even when out. Also, new pads need BREAK IN, if you were hard on them the first 50 miles or so then you could have glazed them over. My truck brakes just started squeeling even with new rotors and pads... I chocked it out to "character", if nothing is wrong then im ok with that.

 

[pannayar]

What is the physics?

Ok, this is purely from a critical reasoning / physics point of view. Please save your energy if you are going to yell "holy shit".

We said 'god forbid' for WD40/kerosene touching the rotor. But won't they evaporate away? It was said that it will lubricate the hell out of the brakes. A lubricant is one that stays in place and provides lubrication, is it not? How can/will that reduce the co-efficient of friction (making it dangerous) for good?

I had/have these questions lingering in my head, the answers to some of which I have learnt and am learning.

Yes, experience is knowing what will happen, and not necessarily why. And mine in some of these departments is near minus two seventy three celsius - if you know what that is.

 

[splat]

My last comment was a joke. Don't use any oil on your braking surfaces (rotor or pads). In fact, to make it easy, don't use ANYTHING except brake cleaner on your brakes. (the pins are a different story)

In all honesty, your best bet is to take varying degrees of sand paper to your rotor to get rid of any glazing, hit it up with brake cleaner, then making sure nothing comes in contact with it, and let it properly get bedded in.

In case you don't already know, no Armor All on the tires. Not Black Magic, no Meguiar's tire shine, nothing!

There seems to be a mixed idea on the evaporation rate of kerosene or whether it really evaporates, since I'm no scientist, I can't tell you one way or another. But I know it's petroleum/oil based. Just keep in mind it's used in glass cutting because of it's lubrication and penetration ability.

 

[pannayar]

My last comment was a joke. Don't use any oil on your braking surfaces...

Sure, but it wouldn't be very funny if someone fell for it (and rode to the school or church you mentioned). It may not be a bad idea to edit it.

Kerosene is petroleum/oil based. it does not evaporate.

That is puzzling to me. Are you sure?

In case you don't already know, no Armor All on the tires. Not Black Magic, no Meguiar's tire shine, nothing!

Thanks for pointing it. I have not used any of them. Since you brought up tires - would a very slight amount of wd40/kerosene/isopropanol be bad if it touched the sidewall of the tires?

 

[ST Guy]

Ok, this is purely from a critical reasoning / physics point of view. Please save your energy if you are going to yell "holy shit".

We said 'god forbid' for WD40/kerosene touching the rotor. But won't they evaporate away? It was said that it will lubricate the hell out of the brakes. A lubricant is one that stays in place and provides lubrication, is it not? How can/will that reduce the co-efficient of friction (making it dangerous) for good?

I had/have these questions lingering in my head, the answers to some of which I have learnt and am learning.

Yes, experience is knowing what will happen, and not necessarily why. And mine in some of these departments is near minus two seventy three celsius - if you know what that is.

Kerosene and even gasoline/white gas/etc. will leave petroleum deposits. It doesn't all evaporate away. And WD40 is specifically designed to leave a deposit when the carrier evaporates.