Brake pads

[kefconstruction]

I'm wondering if this is normal after about 200 miles the pad seems to have seriously deteriorated noticed a sequel while out on Saturday just taken pads out to clean and noticed this, brakes are
TRP Trail Evo, 4-piston, sintered metal pads, 220mm front rotor, 203mm rear rotor

 

[Eduardoramundo]

That can happen even after ONE very wet ride. You have failed in your maintenance tasks. Replace them earlier. You may have damaged your discs as well now. Check them regularly.

 

[Montana St Alum]

That's a lot of wear for 200 miles. The broken spring may have allowed the pad, at least on one side, to move out of position. I suppose that could explain the wear pattern. But no, that's not normal wear.

 

[JP-NZ]

Definitely not normal.

 

[Stihldog]

I don’t think the rotor is any better. Metal on metal …and the heat that causes. Check for rotor wobble also. Make sure the callipers are centred and secured. Test that each piston is moving correctly.

 

[irie]

Broken spring could certainly do that. What's the rotor look like, pretty nasty I'd bet?

 

[RustyIron]

Yeah, I don't think you have many rides left on those pads.

 

[KnollyBro]

I'm wondering if this is normal after about 200 miles the pad seems to have seriously deteriorated noticed a sequel while out on Saturday just taken pads out to clean and noticed this, brakes are
TRP Trail Evo, 4-piston, sintered metal pads, 220mm front rotor, 203mm rear rotor

View attachment 129503 View attachment 129504 View attachment 129505

OMG man.... how did you not hear the brakes making a horrible sound every time you applied them for the last 25 miles? What kind of trails are you riding on, puddles of mud? At least it you are OK and its only money to repair the issue.

 

[E Bob]

Has he worn the spring away, along with most of his pads ? Dude really needs look after his bike, Check your pads after every wash..
Had a bike shop put one pad in backwards once... got a new disk and set of pads out of them.

 

[irie]

If the pads were fitted with the spring in front of (instead of behind) the pad then I guess that's what you could get. If so, the rotor will be toast and as @KnollyBro says, must have made a hell a racket.

 

[E Bob]

that spring is supposed to go inside "or infront of" , not outside.. its to push the pads apart, so back off the disk

 

[Shjay]

Should have gone Magura…..

 

[hainman]

This has happened before when the pad surface delaminated off the back plate and the spring was destroyed

 

[E Bob]

it's not due to a bad, faulty pad, he's just worn them away and not noticed.

 

[steve_sordy]

That is a symptom of not bedding in new pads properly.

I failed to properly prepare a bike I was lending to a mate who was visiting from abroad. I fitted new pads to the rear, but forgot to bed them in. When I remembered, it was too late so I asked him to bed them in as we set off on the trail (there was a group of us). It was raining heavily and the notoriously gritty trail was very wet. I was at the front and he was at the back, so I couldn't keep an eye on him.

He never said anything to me, but he went through both pads to the backing plate and destroyed the springs in 12 miles!

 

[Cb750stu]

That is a symptom of not bedding in new pads properly.

I failed to properly prepare a bike I was lending to a mate who was visiting from abroad. I fitted new pads to the rear, but forgot to bed them in. When I remembered, it was too late so I asked him to bed them in as we set off on the trail (there was a group of us). It was raining heavily and the notoriously gritty trail was very wet. I was at the front and he was at the back, so I couldn't keep an eye on him.

He never said anything to me, but he went through both pads to the backing plate and destroyed the springs in 12 miles!

Were they made of butter and was he cycling with the brakes on

 

[E Bob]

Were they made of butter and was he cycling with the brakes on

Chocolate I think, Milky Way… Pads won’t wear super fast if they have not been bedded in properly, you may get squeaks or a judder, but now way do sintered pads wear away on one little trail ride, theres probably a racing pad that’s short lived, but that will be the big boys abusing brakes. Iv swapped from carbon back to sintered on a race bike, R1, And destroyed both the disks and pads in one race, brembo T disks too… But that’s was because I didn’t remove the carbon from the disks properly, not relevant to this though

 

[steve_sordy]

Were they made of butter and was he cycling with the brakes on

They were the same pads as I always fitted at the time, Shimano sintered something or other. The brakes were fine when I checked the bike over before and after the ride (except the pads after). His normal stamping ground was in Greece, near Athens, so the continuous heavy rain was not to his liking. This was all pre emtb.

 

[E Bob]

Thats Unbelievable...

 

[irie]

that spring is supposed to go inside "or infront of" , not outside.. its to push the pads apart, so back off the disk

That's what I meant. We use the same shaped pads on our Trek Rail 4 piston Shimano calipers. Looked to me like the spring may have been fitted crooked with one end in front of the pad surface.

 

[E Bob]

That's what I meant. We use the same shaped pads on our Trek Rail 4 piston Shimano calipers. Looked to me like the spring may have been fitted crooked with one end in front of the pad surface.

He's just wore all the surface away, spring along with it

 

[irie]

He's just wore all the surface away, spring along with it

Given that one side and other end of the damaged spring appears to be competely intact, why is only one end of one side of the spring worn away? Need to see both sides of the rotor.

 

[kefconstruction]

Will get a pic of rotor later, ride a lot in rain and mud!! But shouldn't do that, never even botherd checking pads since having it, but I will now going forward

 

[kefconstruction]

it's not due to a bad, faulty pad, he's just worn them away and not noticed.

But only one side?

 

[kefconstruction]

That is a symptom of not bedding in new pads properly.

I failed to properly prepare a bike I was lending to a mate who was visiting from abroad. I fitted new pads to the rear, but forgot to bed them in. When I remembered, it was too late so I asked him to bed them in as we set off on the trail (there was a group of us). It was raining heavily and the notoriously gritty trail was very wet. I was at the front and he was at the back, so I couldn't keep an eye on him.

He never said anything to me, but he went through both pads to the backing plate and destroyed the springs in 12 miles!

What would be best way to bed in?

 

[kefconstruction]

OMG man.... how did you not hear the brakes making a horrible sound every time you applied them for the last 25 miles? What kind of trails are you riding on, puddles of mud? At least it you are OK and its only money to repair the issu

That can happen even after ONE very wet ride. You have failed in your maintenance tasks. Replace them earlier. You may have damaged your discs as well now. Check them regularly.

Definitely will check them alot more

 

[steve_sordy]

What would be best way to bed in?

There are absolutely loads of YouTube vids on how to do it. Of the many I have seen they appear to be two main ones:
Ride your bike with dry pads.
Ride your bike with wet pads.

I have always done it dry as it is less faff and it works OK, when I do it properly.

PS: Try to avoid tyre squeal as it shows that you have locked up the wheel and not building up friction on the pad/disc interface.

 

[hainman]

Seen a few ways on bedding pads in
Huge sharp stoppies
Or slow brake dragging
I find Shimano bed in really quickly but I always rub the pads on a hard surface to take the top layer off first

 

[E Bob]

i wouldent put too much thought into it, pads wear uneven, 2 pot, 4 pot, its just how it is, yours look quite even actually. You just need check your brakes every few rides. Do it after you wash the bike. Theres also no rocket science in bedding pads in, its only to clear off the surfaces, just go steady on the brakes for a few mins, No long drops getting them hot,simples.
But it wasn't not bedding them in that done that to your pads, its the fact you didnt check them.

 

[Mikerb]

The damage to the spring is the clue. The spring was not fitted properly in the first place which means the brake pad was not releasing from the rotor on one side and being presented to the rotor at an angle when the brakes were re applied. The accumulated rubbish on the pad shows that it was not being wiped......it only gets wiped by the rotor if the contact is along its full width front to back.
Those pads are toast...........best to check the rotor for damage as well.

Brake pads have a sacrificial initial layer. Bedding in is merely a process designed to remove that layer without causing the main material surface to glaze. The way to do that is to first clean the rotor with IPA/brake cleaner, then ride the bike, preferably on tarmac and apply the brakes quite hard but only for a second or two..without making the wheel skid. Dragging the brakes will cause too much heat build up and glaze the pad...hence short stabs at the brake. It literally takes only about a dozen of those short stabs to complete the bed in.