[strawloki]

Sounds like you did everything right - I think you got a bad set of pads. You'd have to be putting in a ton of vert to wear metallic pads down to the backing plate in a month, and chipping is never normal.

Just touching the pads while installing isn't going to cause the symptoms you're describing (unless your hands were covered in grease/oil) but it does sound like they may have gotten contaminated somehow. It's possible that your calipers are leaking and causing problems.

I have thought of the caliper possibly leaking but the pistons never fell out or anything like that. They are kinda dirty however with tons of brake dust, I was thinking maybe some of the brake dust came loose and got between my rotor and pad? I always forgot to try to clean the caliper with brake clean and inspect for leaks.

 

[strawloki]

I think the only thing you did wrong was get your brake pads too hot-you messed up by riding too fast while weighing too much, causing your pads to glaze. The fact that the same thing happened over and over after you sanded the glaze off is the giveaway to me. You need to keep your brake pads cooler with bigger rotors or buy different pads and hope they are harder to glaze. Maybe try finned metallics.

Right but I've heard from numerous sources that metallic pads can take a lot of heat compared to resins? Then again if I'm not mistaken metallic pads do generate more heat than resins and on an equivalent braking test the metals would get hotter? The situations that I'm in do involve like 3-6 seconds of standing on the brakes hard.

 

[strawloki]

If they're down that quick something is wrong unless you've been at a bike park all month?

Just get some new pads, I reckon you're over thinking this. Leave the rotors alone unless you've actually spilled something on them. Constantly sanding the rotors down means you're going back to square one. I got new brakes recently and honestly it's the first time I looked up bedding procedure after almost a decade of Shimanos
With my SLX and Saints I'd never bother bedding in new pads. I'd put them in, checked that they worked and simply go ride. I think a tonne of it is overblown and is possibly manufacturers covering themselves.

It sounds like you may have been unlucky with a set of pads. I've never had a set wear down that quick with normal riding. I have had a set of pads where the friction material actually fell off the backing plate. Genuine Shimanos and a walk back to the car.

Well this time around there's some clear-ish streaking on the rotor so I'll sand it once more before getting new pads, as I know that the rotor can get glazed too. They did wear a bit uneven probably because I installed the brake hardware backwards left to right, which lead to my chipping issue. I do ride very frequently and I'm put in situations where I have to come to almost a stop quickly, standing on the brakes for about 3-6 seconds each time HARD. I've been advised to switch to resin. Should I give metallics another try or switch to resins for my use case?

 

[norcalbike]

Those pads should last a good long while even if you are a hea

Right but I've heard from numerous sources that metallic pads can take a lot of heat compared to resins? Then again if I'm not mistaken metallic pads do generate more heat than resins and on an equivalent braking test the metals would get hotter? The situations that I'm in do involve like 3-6 seconds of standing on the brakes hard.

those shimano pads are normally pretty resilient. I think you got duds

 

[Mudguard]

I've been advised to switch to resin. Should I give metallics another try or switch to resins for my use case?

If you have gone through metal pads that quick then resin pads won't last very long at all.

 

[Gilarider]

You are overthinking this. You need new brake pads anyway, 'cause you sanded the life out of them. Just try better pads, like finned metal, or Galfer Pro, and see if those work. If you are still glazing get bigger rotors.

 

[norcalbike]

You are overthinking this. You need new brake pads anyway, 'cause you sanded the life out of them. Just try better pads, like finned metal, or Galfer Pro, and see if those work. If you are still glazing get bigger rotors.

There no way Galfer pro is going to last as long as Shimano metallic. I’m dubious on whether the cooling fins do much either.

 

[jeremy3220]

Can you take a picture of the rotors and pads?

 

[strawloki]

Can you take a picture of the rotors and pads?

Will post one tomorrow

 

[strawloki]

There no way Galfer pro is going to last as long as Shimano metallic. I’m dubious on whether the cooling fins do much either.

I'm open to other pads, but I don't know if they'll fit right on my caliper (i.e pad not covering the entire rotor)

 

[Gilarider]

There no way Galfer pro is going to last as long as Shimano metallic. I’m dubious on whether the cooling fins do much either.

OP needs new pads. Are you saying just buy what they already have that doesn't work?

Galfer pro's will last longer if OP doesn't have to sand them down after every ride. And they will stop better while they last.

Or, let OP buy the finned pads and prove you right. At least they will have tried something different that theoretically will heat up less.

What are your favorite pads for dealing with heat?

 

[norcalbike]

OP needs new pads. Are you saying just buy what they already have that doesn't work?

Galfer pro's will last longer if OP doesn't have to sand them down after every ride. And they will stop better while they last.

Or, let OP buy the finned pads and prove you right. At least they will have tried something different that theoretically will heat up less.

What are your favorite pads for dealing with heat?

I run Trickstuff power+ pads that deal well with heat. Also occasionally dabble with the Galfer E-bike pads (purple) in the rear for longevity and slightly less braking power.

in my experience, the basic shimano metallic pad has better fade resistance and wear characteristics than both of these, which is why I’m inclined to think OP got some fake ones or duds.

 

[nwberm]

IMO no reason to discard the existing brand/model of pad as though it's not a bad set of pads. Sounds like a bad set of pads. At least buy another set and see.

 

[Gilarider]

I run Trickstuff power+ pads that deal well with heat. Also occasionally dabble with the Galfer E-bike pads (purple) in the rear for longevity and slightly less braking power.

in my experience, the basic shimano metallic pad has better fade resistance and wear characteristics than both of these, which is why I’m inclined to think OP got some fake ones or duds.

I can fade Galfer purples, but never faded Galfer pros, so I recommended those. Sounds like power+ are out.

OP swears their pads aren't fake, so for everyone that thinks the pads are bad/duds, how many times has that happened that you know of? Were they shimano metallic? I would think the chances are slim the pads are defective, and if they were contaminated they wouldn't start working after they were sanded, and they wouldn't bed in.

We are talking two piston brakes that appear to work while bedding in and appear to glaze over in use and then work again when the pads are sanded. Isn't this a classic overheating scenario?

 

[Cleared2land]

Some interesting assumptions going on here.

 

[dwyooaj]

I have read not to use brake cleaner on the rotors as it leaves a residue. Bike brakes don't get as hot as car brakes to burn it off. Just use IPA.

Yup. and this is possibly the whole problem if OP keeps using it. get new pads and either torch or replace the rotors if thats the case and from now on isopopyl alcohol only. Brake cleaner is for cars, auto brakes get hot enough to burn that residue off and are far less sensitive to contamination than lightweight finger-powered mtb brakes.

 

[William P]

Bedding in organic pads is very important for a different reason than metallics. You actually need to get the pads hot enough to release the oil in the surface layer to produce a "dry" layer on the pads. In use this dry layer then works it's way down through the pads as they wear. If not done properly the first hard stop greases the rotors.
Shimano offers several upgrades to remove heat before it gets to the pads, and before it gets to the 2 piston calipers.
Shimano Icetech rotors from the XTR/Saint groupset. They run much cooler than solid steel rotors. Freeza versions run even cooler and have more metal to prevent bending. They dump a lot of heat before it get's to the pads. RT-86 are the 6 bolt Icetechs, RT-M905 are the 6 bolt Freezas. They used to be Centerlock only.

ICE TECHNOLOGIES FREEZA | SHIMANO BIKE-EU

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bike.shimano.com

With the problem you're having you should probably step up to the 203mm size. If you stick with 180 I would get the Freezas.
Shimano J04C pads may help solve your problem. But with brakes I would want a bigger safety margin than that.

SHIMANO DISC BRAKE PAD METAL WITH FIN J04C-MF 1 PAIR | SHIMANO BIKE-EU

SHIMANO DISC BRAKE PAD METAL WITH FIN J04C-MF 1 PAIR. SHIMANO Original parts and the right maintenance makes this excitement possible for you, every day.

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[William P]

Planet Cyclery is having a going out of business sale. They have some Centerlock rotors on sale there. M800, M900 are the numbers for those.

Sorry about that I see you're using the RT-66 which are 6 bolts. The RT-86 can be found discounted several places. If money is tight the 180mm can be found around $45 at Jenson. Discounts on the M905 are harder to find.

 

[Cleared2land]

Does the OP have centerlock hubs?

 

[strawloki]

Does the OP have centerlock hubs?

Nope, 6 bolt, Forgot to specify, it's a 2012 Trek X-Caliber.