TRP DH-R evo pads constantly glazing

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TRP DH-R evo pads constantly glazing
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flag Keegansamonster
Posted: Aug 3, 2021 at 10:01 Quote
My month old dhr evos are constantly glazing. They are always properly bedded in and ride great until the bike sits for 2-3 days. After it sits, there is no braking power, and they squeal like crazy. My trails are definitely not steep or fast enough to cause glazing and it never happens on the trail. I can drop the pads, sand, and re-bed them and they work fine again until the bike sits for a few days again. It’s super confusing because it’s never happened with any of my other sets of brakes. Any ideas?
flag Branmuffin
O+
Posted: Aug 3, 2021 at 18:29 Quote
Keegansamonster wrote:
My month old dhr evos are constantly glazing. They are always properly bedded in and ride great until the bike sits for 2-3 days. After it sits, there is no braking power, and they squeal like crazy. My trails are definitely not steep or fast enough to cause glazing and it never happens on the trail. I can drop the pads, sand, and re-bed them and they work fine again until the bike sits for a few days again. It’s super confusing because it’s never happened with any of my other sets of brakes. Any ideas?

Pads are probably contaminated. I have had a similar issues before and just had to replace the pads.
flag Keegansamonster
Posted: Aug 3, 2021 at 20:20 Quote
Branmuffin wrote:
Keegansamonster wrote:
My month old dhr evos are constantly glazing. They are always properly bedded in and ride great until the bike sits for 2-3 days. After it sits, there is no braking power, and they squeal like crazy. My trails are definitely not steep or fast enough to cause glazing and it never happens on the trail. I can drop the pads, sand, and re-bed them and they work fine again until the bike sits for a few days again. It’s super confusing because it’s never happened with any of my other sets of brakes. Any ideas?

Pads are probably contaminated. I have had a similar issues before and just had to replace the pads.

That’s what I thought……this is my third set of pads….
flag bdreynolds7
O+
Posted: Aug 3, 2021 at 20:48 Quote
Posted on MTBR but here it is again.

I felt the same with my new Trail Evos. What I did to fix it was the following:

-No more automotive brake cleaner
-Only use the highest percentage isopropyl alcohol with a clean rag to clean rotors and components
-Heat brake pads (I assume TRPs performance resin?) with propane, Mapp gas torch or oven (not too much but enough to burn off the contamination)

I found that the bleed screw on the caliper still had mineral oil in the threads from the factory bleed. This led to the oil seeping out of that area and onto my pads on my first ride. Prior to installing pads AFTER cleaning everything with isopropyl and heating your pads up, used compressed air to clear out the mineral oil hanging out in bleed plug screw threads. Then put your pads back in and rip it! I did all of this and didn’t have any issues last weekend at my first enduro race
flag murlsquirl
O+ FL
Posted: Oct 19, 2022 at 6:37 Quote
Keegansamonster wrote:
My month old dhr evos are constantly glazing. They are always properly bedded in and ride great until the bike sits for 2-3 days. After it sits, there is no braking power, and they squeal like crazy. My trails are definitely not steep or fast enough to cause glazing and it never happens on the trail. I can drop the pads, sand, and re-bed them and they work fine again until the bike sits for a few days again. It’s super confusing because it’s never happened with any of my other sets of brakes. Any ideas?

I know this is old, but what ended up being the issue? Having the same exact problem. Waiting on new pads to come in and hoping that fixes the issue. It's annoying as hell because the front has been perfect from the start, but the rear has been doing this since I got them a month ago.
flag k2theg
O+
Posted: Oct 19, 2022 at 7:41 Quote
What pad compound are you guys using? I've used the sintered pads from day one and have never had any issues and they have been very quiet.
flag murlsquirl
O+ FL
Posted: Oct 19, 2022 at 7:44 Quote
k2theg wrote:
What pad compound are you guys using? I've used the sintered pads from day one and have never had any issues and they have been very quiet.

Resin pads they came with. I'll be switching to the MTX gold I usually run when they come in on Friday.
flag jray152
Posted: Oct 19, 2022 at 8:25 Quote
TRP DH-R EVO WOES

After I installed my brakes and trimmed the lines, I did the lever bleed only. Front was perfect and never had to touch it. Rear would pull in further after a couple pumps so I decided to do a full bleed. Having Code RSCs on many bikes for the last 5 years, it seemed straight forward. However, after about 10 minutes of bleeding and still seeing bubbles I started taking a closer look at everything to see what was going on.

The bleed hose connection at the caliper bleed port does not seal well. The o-ring on the hose sits flush on top of the flat part of the caliper. Too tight and the o-ring squishes out, losing the seal. Too loose and the o-ring doesn't seal at all. This is a poor design. There should be a recess or bed for the o-ring to sit inside and create a seal.

Also. I am not putting ANY type or ANY amount of loctite on a screw this small using a T15 torx. That is a stripped screw waiting to happen.

Eventually I found a sweet spot for the syringe after about 10 minutes and 5oz of fluid leaking out of the caliper while I fussed with it.

After finishing the rear and cleaning the puddles of fluid off the floor and the caliper, I went out for a ride. All good.

About a week later I went to the bike park, absolutely no issues with the brakes at all at any point super happy with them driving home.

Few days later I pull the bike out to go for a trail ride and the front brake is SOOOOFFFTTTT. First pull goes almost to the bar. "THATS F*CKIN WEIRD" I say to the dogs as they wait to go for a bike ride. Quickly I do a lever bleed just to be sure, no bubbles... ok... We go for a ride and theres no issues.

At the end of the ride I go to practice some stoppies and the front brake makes the loudest squeal I've ever heard. It sounded like metal on metal. WTTTFFFFFF.

I can see a few spots on the pads where they've definitely got some fluid on them... how? No idea. I swap the pads, clean the hell out of the rotor. install. Test. SQUEEAALLLL. WTF!!!

Remove everything. Bleed. New pads. Clean rotor. cycle the pistons. LOTS OF ALCOHOL. Dry. install. SQUEAAALLLLL.

alright man... they're for sale. Im not doing this.
flag DCF
FL
Posted: Oct 19, 2022 at 20:36 Quote
I'm experiencing the same thing as jray152 and it hurts. Luckily I kept the rsc. At first the were the best thing ever. Now they are contaminating everything and I can't figure out what tf is happening.
flag HeatedRotor
FL
Posted: Oct 19, 2022 at 20:50 Quote
Its the Bleed ports i believe, Loctite fixed mine
flag Keegansamonster
Posted: Oct 19, 2022 at 21:26 Quote
murlsquirl wrote:
Keegansamonster wrote:
My month old dhr evos are constantly glazing. They are always properly bedded in and ride great until the bike sits for 2-3 days. After it sits, there is no braking power, and they squeal like crazy. My trails are definitely not steep or fast enough to cause glazing and it never happens on the trail. I can drop the pads, sand, and re-bed them and they work fine again until the bike sits for a few days again. It’s super confusing because it’s never happened with any of my other sets of brakes. Any ideas?

I know this is old, but what ended up being the issue? Having the same exact problem. Waiting on new pads to come in and hoping that fixes the issue. It's annoying as hell because the front has been perfect from the start, but the rear has been doing this since I got them a month ago.

Mine ended up just being the resin compound. It works great on the front but was awful in the rear. I switched to their sintered pads and they have been amazing. Going on a year or so now with no issues and haven’t even had to bleed them. Been amazing.
flag Keegansamonster
Posted: Oct 19, 2022 at 21:28 Quote
jray152 wrote:
TRP DH-R EVO WOES

After I installed my brakes and trimmed the lines, I did the lever bleed only. Front was perfect and never had to touch it. Rear would pull in further after a couple pumps so I decided to do a full bleed. Having Code RSCs on many bikes for the last 5 years, it seemed straight forward. However, after about 10 minutes of bleeding and still seeing bubbles I started taking a closer look at everything to see what was going on.

The bleed hose connection at the caliper bleed port does not seal well. The o-ring on the hose sits flush on top of the flat part of the caliper. Too tight and the o-ring squishes out, losing the seal. Too loose and the o-ring doesn't seal at all. This is a poor design. There should be a recess or bed for the o-ring to sit inside and create a seal.

Also. I am not putting ANY type or ANY amount of loctite on a screw this small using a T15 torx. That is a stripped screw waiting to happen.

Eventually I found a sweet spot for the syringe after about 10 minutes and 5oz of fluid leaking out of the caliper while I fussed with it.

After finishing the rear and cleaning the puddles of fluid off the floor and the caliper, I went out for a ride. All good.

About a week later I went to the bike park, absolutely no issues with the brakes at all at any point super happy with them driving home.

Few days later I pull the bike out to go for a trail ride and the front brake is SOOOOFFFTTTT. First pull goes almost to the bar. "THATS F*CKIN WEIRD" I say to the dogs as they wait to go for a bike ride. Quickly I do a lever bleed just to be sure, no bubbles... ok... We go for a ride and theres no issues.

At the end of the ride I go to practice some stoppies and the front brake makes the loudest squeal I've ever heard. It sounded like metal on metal. WTTTFFFFFF.

I can see a few spots on the pads where they've definitely got some fluid on them... how? No idea. I swap the pads, clean the hell out of the rotor. install. Test. SQUEEAALLLL. WTF!!!

Remove everything. Bleed. New pads. Clean rotor. cycle the pistons. LOTS OF ALCOHOL. Dry. install. SQUEAAALLLLL.

alright man... they're for sale. Im not doing this.

Sounds like you have a cracked piston. Happens on most manufacturers. I’ve gone on a year now without even needing a bleed. I’ve got 3 or 4 other local riders on them and no one has had an issue.
flag jray152
Posted: Oct 20, 2022 at 6:24 Quote
Update:

I called TRP and asked a few questions to be sure I wasn’t doing anything wrong.

I explained I’ve been on code RSCs for a looong time and I’m not stupid when it comes to bleeding brakes, or tips and tricks to get them dialed.

Big answer here: the blue organic pads that come in the calipers when purchased are a “race” specific compound. From TRP tech: “if you heat up the pads during a run, then practice a couple stoppies, you’re melting the pads on the rotors and they’re done after that”.
Which is exactly what I was doing lol, rear pads are the blue organics and the rotor is just fine.

So run the red semi Metallic pads or full metals unless you’re racing DH.

They’re sending me a new rotor, semi metallic pads, and a new oring for one of the bleed syringe hoses. +100 points for customer service.

He also explained a proper bed in process is more tedious and complicated than other brands. Which would explain all the glazing problems. Basically you just have to do the “speed up and slow down” a few more times and with less force on the lever than you normally would.

As far as bleed goes, when attaching the syringe to the caliper, just have to be extremely cautious not to squish the oring but still snug it up enough to create a seal. That’s gay but I’ll live with it. He agreed that using old pads with a piece of rotor is better than a bleed block. And using the syringe hose instead of the bleed cup on the lever. Syringe hose has a larger diameter orifice.
flag murlsquirl
O+ FL
Posted: Oct 20, 2022 at 7:52 Quote
I just went through the whole process again yesterday (clean rotor, sand glazed pads, bed in etc.) and they were glazed after one short and not steep ride. Front is still perfect.

Going to clean the rotor good tonight, throw on the new MTX pads, and hope the issue is fixed. I ordered directly from them so glad to hear the customer service is great if I still have problems.
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