Do sintered Pads go "Off" ?

[DavieSV]

My front discs are rusty as a rusty thing.
A quick ride soon cleans them off, but they rust again within hours.
If I leave the bike for a few days after riding in the rain, the pads stick to the disc and need a good shove to break them off.

Now I'm under the belief that sintered pads transfer some of the material to the disc to create the friction required (I may be wrong :confused:).

So is it this material that is rusting?
and also, because of the nature of sintering, the pads must be porous, so are my pads thoroughly soaked in water/salt creating the pads to corrode from the inside?

I have some new pads on order, but was just curious.

By the way, GSXR 750 K7 radial callipers on SV1000 disc.

John.

[Sid Squid]

Sintered pads are made from a powder that is heated to fuse the particles together, some constituents of the pad are ferrous metals, it's these that corrode and cause the pad to stick to the disc, which is completely normal and not a sign that they are 'going off'.

[DavieSV]

But surely if they are corroding, then they are deteriorating. (ie going off).

[DJ123]

But surely if they are corroding, then they are deteriorating. (ie going off).

Ferrous metals rust. With brake pads and discs a new surface is being revealed every time you use the brakes. This is why most cars/bikes will get a surface rust on them when there is lots of moisture in the air.

[DavieSV]

http://img.tapatalk.com/d/14/01/07/hu2u6e2y.jpg

1 1/2 hours after getting home :-o
You can see on the tyre where the rust has been scraped off previously.

[DJ123]

Are your discs near the near minimum thickness mark?

[DavieSV]

I don't know about that.
I'll mic them up tomorrow.

[DavieSV]

That shouldn't make a difference though should it?

[dizzyblonde]

EBC discs by any chance?


If they are, mine do the same. Rust after an hour of standing still.

[DavieSV]

Suzuki quality ;-)

[DJ123]

That shouldn't make a difference though should it?



They might be a different material/compound as the disc gets thinner to prevent the disc from rapidly warping as the material layer lessens. I don't know if this is the case though (similar to tyres)

[DavieSV]

So then, in the name of science...
My new pads should be here this week.
If I change just one set and they rust just as quick, then that will prove that age makes no difference and therefore they do not deteriorate.
However, if the disc with new pads on stays cleaner, that should prove that they do deteriorate.
I've said with age, but that is not strictly true. Exposure to the elements may be more of an accurate description.

Variables...
Which side?
Should I clean the surface of the disc before fitment?
Should I try to clean the old pads?

[jambo]

They might be a different material/compound as the disc gets thinner to prevent the disc from rapidly warping as the material layer lessens. I don't know if this is the case though (similar to tyres)

The material is uniform through the thickness. In this case it's the discs not the pads that are rusting I think. Not all discs are made of exactly the same type of steel. Some types of steel rust more easily than other. The selection of metal was probably made for reasons of heat dissipation, resistance to warping, friction, and cost.

Things rust fastest in warm, wet conditions with a catalyst like salt. Guess what conditions those GSXR/TL discs have been in?


Jambo

Sent without a real keyboard

[dizzyblonde]

That's the reason why I asked what discs they were.

Ebc discs are notorious for turning orange if you so much as sneeze at them. I can gaurantee they are orange now! They aren't wearing thin either....not even worn in yet ;)

So, Suzuki iron it is then Davie :p

[admin]

Blimey, neither of my SV's had discs go that rusty and that included being left outside all winter.

sent from my Moto G

[DavieSV]

That's the reason why I asked what discs they were.

Ebc discs are notorious for turning orange if you so much as sneeze at them. I can gaurantee they are orange now! They aren't wearing thin either....not even worn in yet ;)

So, Suzuki iron it is then Davie :p

But why now?
Why not last winter or the winter before???
Same run to work, same conditions, stored the same...

[DJ123]

Might be more salt on the roads maybe? Acid rain erosion? More humidity in the air?

[DavieSV]

It's not just happened today, been like it for last two or three months.
It was just highlighted today after being stood all over Christmas and I had to drag it up the drive to free it this morning.

[dizzyblonde]

But why now?
Why not last winter or the winter before???
Same run to work, same conditions, stored the same...

Ummmmm dunnoooo :-?

Can't offer any other possibility in that case!

[Sid Squid]

All Japanese OE discs are made of materials that do not readily corrode, this is for appearances sake mostly, many older Italian bikes had iron discs that corroded if you parked near a damp sponge, the material of the disc is very important in this question, what are your discs made of?

[m`baubz]

doesn't seem to me that suzuki have anything to do with this.
the discs look like they could be EBC prolites. if so, then they're made of a different kind of steel
(which ebc say is different still from the racing "iron" discs, but that's another thing), and it's normal for them to rust instantly.

oem discs are stainless steel, so better suited for commuters.