Squealing brakes

I have a 1992 750 ninja with dual hydraulic front disc brakes. I have
tried EBC pads in both the "organic" and the "HH" formulations and
both screech badly when cold. If I work the brakes to heat them up
the noise stops and it is less common in warm weather. I looked at the
pads and don't see any signs of odd wear and cant find anything that
might be dragging on the calipers that shouldn't be. I can't tell if
it is just one brake or both front brakes. The discs are in better
shape visually than the discs on most other bikes I have owned. This
is driving me nuts and is embarrassing besides.

Thank you for any help.

 

--------

EBC pads?

<mythbusters>There's yer problem!!<mythbusters>

Get rid of that cheap-ass shit and buy OEM Kawasaki pads.

I've also had EBC pads score my rotors in addition to being noisy no
matter what antisqueal shims I did or did not fit.

-gc

 

Brake pad squeal is caused by a resonance between the pad and the disk.
It's like dragging your fingernail across a chalk board.

Pad squeal gets worse with harder brake pads.

Brake pads are always skimming the surface of the disk lightly, they
have only about 2 or 3 thousandths of an inch of clearance.

As the pads intermittently touch the rotors, the surface of the pad
gets hard and you will notice that the fiber matrix holding the little
metal bits gets shiny.

This is called "glazing" and the solution for pad glazing is to remove
the pads and work them in a figure-8 pattern on a piece of sandpaper
laying on a flat surface. A sheet of glass makes a nice flat surface.

But the glazing will return if you don't use your front brakes hard
occasionally. I used to hear the front brakes on my old GT-750 Water
Buffalo squealing constantly because I was a rear brake user and didn't
use the front brakes hard.

Also, stainless steel rotors that aren't drilled will squeal worse than
any other type of rotor. GT-750's came with undrilled, stainless steel
rotors...

 

And you're still alive to tell the tale? Blimey.

 

Thank you. I will try that along with some of the other suggestions I got.

 

I would ride the Water Buffalo 100 miles every day of the week in those
days, putting 25K miles a year on the machine while exploring all the
canyon roads leading to the beaches, but my average speed was only
about 45 mph.

The double disk brakes were more suitable to vigorous sport riding, so
they didn't get used hard enough to knock the glaze off the pads, and
they would "sing" at an annoying high pitch as the rotors turned.

I would loosen up the caliper bolts, rock the calipers just enough to
slip a strip of 3M wet-dry sandpaper (grit side out) between the disk
and pad, pump the brake lever to clamp the paper against the rotor, and
slide the paper back and forth to de-glaze the pads.

The other maintenance trick was to reposition the rear brake arm after
about 7K miles so it wouldn't hit the rear axle when I applied the
brakes.

One Honda rider was baffled by what I was doing as he watched me
reposition the arm in
the Griffith Observatory parking lot. He asked why I didn't do that at
home.

I told him that I was at home on the Water Buffalo, wherever it was,
but he was just a "weekend warrior" who didn't understand the biker
lifestyle.

I used to clean my spark plugs and clean and gap my ignition points
while the RUB's were busy brown-nosing each other. They all thought I
was the weird one, but they had to take their own machines to a
$tealer$hip just to have the air changed in their tires
every spring...

 

Well, yeah, I wouldn't ride anything fast either, if I was just relying
on the back brake.

Heh. The trick is not to adjust it so far that it over-centres....

 

The old fashion and most used product is copper grease, a much better
solution(albeit more expensive) is aluminium grease.

Clean the calliper where the pads ride for all non-belonging material.
Then smear a thin cote on all of the contact surfaces, including the
edges. Forget the latter, and it will squeal...

J.

 

I pack the shims behind the pad and the pins with wheel bearing grease.
(wheel bearing grease don't melt) It attracts brake dust and dirt and
makes changing them more messy but it stops the squeaking. I hate
squeaks. When I need new pads I clean everything up and re-grease it.

 

Is this Nomen Nescio again?

I've heard about using copper grease on the *pins* that single-sided
calipers slide on, they have o-rings to seal grease in and British
riders use the copper grease because
they salt the roads and calipers corrode and get stuck.

But this poster makes it sound like he's putting grease on the backs
and edges of the brake pads.

Now, what is grease? It's a lubricating agent of some sort in a binder
that melts at some temperature. If the lubricating agent is powered
copper or aluminum in something that melts, what's to stop the melted
stuff from getting on the calipers and the working face of the brake
pads?

 

Grease is a generic term, as in "Grease", containing soap and
lubricants, and wait for it..... Comes in different heat tolerance ranges.

And yes, I do apply it to the back of the pads, and the edges.

The only place it is not used, is in true racing applications, where
squeal is a non-issue.


J.

 

Copper grease is also known as copper paste, as is the aluminium based
version(Aluminium paste).

J.

 

Over a long period of time, this is the case. The O-rings work
effectively, quite often for many years, but removal of the pins and a
cleane and re-grease is good policy.

What's also important is to grease the pins that secure the pads
*especially* on calipers where the pins go blind into the caliper (and
thus can't be knocked out from the other side). Suzuki bandits are
notorious in this respect.

Yes. So do I.

Using high melting point grease. Next question?

 

What's the melting point of the binder agent?

The peak temperature around here gets up to 100 degrees F everyday for
six months, then we get the cold season where the high temperature is
55 to 60 degrees F.

The temperature on the pavement is probably 150 to 160 degrees F during
the summer, and, if the brakes are used, they probably heat up the pads
to 300 degrees.

If the melting point of the binder is too low, the stuff will drip off
the pads, maybe onto one rotor when the motorcycle gets parked on the
side stand...

 

Look, in the last few days you have:

Told a flat-battery Ducati owner to check his kill switch when the bike
actually spins the engine on said switch.

Given a KE100 owner reams of advice on checking his sidestand ignition
cut-out when the bike doesn't have one.

Told the Ducati owner to look for his battery behind the fairing, when
it's actually under the tank.

Told the Ducati owner to check his sidestand ignition cutout when the
bike doesn't have one.

Given the Ducati owner several hundred words of irrelevant verbiage on
batteries. All he had was an immobiliser which was flattening the
battery over time, for Chrissakes - a well-known issue, and something
that other posters referred to as well.

Given us your perceived wisdom of riding a bike on the back brake only.

And now you're banging on about not using a very specific type of grease
on brakes *when some manufacturers actually include the stuff with the
pads*.

Just accept that, on occasion, the depth of your knowledge is matched by
an equally vast chasm of ignorance and that people may do what you don't
advise, and it works for them.

I've used a very thin smear of brake grease (forget what it's called -
comes in little sachets with some brake pad brands) and/or some very
high melting point grease on pads and pins for decades. I haven't run
out of brakes yet.

It also seems to work for other posters here.

 

As I said previously, greasing brake parts with something like Duckhams
Copper 10 is a British thing, nobody in California needs to do it, as
the roads aren't salted, CalTrans just throws gravel on the snow so
unwary riders can crash after the snow melts.

And you still didn't answer the question about how hot the stuff has to
get before it moves around...

 

You're still likely to get corrosion of one type or another - it'll
just take longer. And as others have said, it helps prevent squeal.

I don't care. I use HMP grease, very sparingly, and I haven't had a
problem in <checks calendar> 31 years of riding. In fact, I've never
had a grease-on-brakes incident in 31 years of riding <sticks finger in
wind> something like 400 different motorcycles. And like I said, it's
SOP here and plenty of other places. Including the US. Why think it's
confined to Britain?

Ah! Wait! I tell a lie! I bought a Kawasaki H1D in, um, oh, must have
been 1996 or 1997, and on the test ride the front disc didn't bite *at
all*, so I went into a bend rather faster than I intended. Bad news on
an old Kawasaki triple.

When I got back and told the seller that the brake had given me a nasty
moment he confessed to having sprayed everything with WD40 before
putting the bike into storage.

Just accept that you're wrong about this.

 

To get the kind of corrosion I saw on 10 year old motorcycles in
England, you'd have to live at the beach in Malibu and park outside for
about three years.

My GS1100 Clymer manual calls for a thin coating of a clear grease on
the calipers' axle pins. The only reason I knew about Brits using
copper loaded grease is from reading motorcycle magazines, and my
Yamaha Haynes manual also mentions using Copper 10 on UK motorcycles.

Well, I *thought* I was wrong, once. But I reconsidered and realized
that I was mistaken...

 

Heh. Trust me, other countries do it as well. The UK, mirabile dictu,
does not have a global monopoly on foul weather.

 

Where did I ever say that I relied on the rear brake only? I said that
I didn't use the front brakes hard enough. So the pads glazed.