Shimano Resin Fin Brake pads (J02A)

[Mintman]

Help please!

 

I bought an M8000 XT brakeset that came with Shimano finned resin pads. They worked perfectly and I really liked them. I never rode in the rain and only commuted short distances. After about two weeks, the rear pads are squealing like crazy and not stopping me at all. I have to pull down really hard on the brake lever, and even then I can't get the rear wheel to lock and slide. The front still works well.

 

I really don't see how the rear pads could have been contaminated because the rotors were brand new and fitted with the brakeset. Obviously contamination can happen so easily though.

 

Does anyone have experience with these resin pads and know how I might repair them?

 

Also, if I can't fix them, would you recommend a metal pad replacement (finned shimano)?

[fanievb]

did you bed the pads before you started using them?

I suggest you lightly sand the surface of the pads, refit and bed them properly

[Mintman]

did you bed the pads before you started using them?

 

I suggest you lightly sand the surface of the pads, refit and bed them properly

 

I probably didn't bed them properly. I took them off and sanded them a bit last night. They aren't squealing as much but there's still no real bite and I can't lock/slide the wheel.

 

How do I go about bedding the pads properly?

[Mr lee]

Pull the pad and give it a good clean....something may have dropped/splashed on the pad or disk which caused the issue.

 

...or re-bleed the rear brakes, especially if they are still newish! 

[dirtypot]

You won't get them cleaned properly - I've tried everything in the past.  You may improve them a bit, but they'll never be perfect.  

Get another set of pads.

If you're not riding in mud, then stick to the resin pads.  Metal will wear out your disc faster, have slightly less bite and have the potential to squeak.  

I've used finned and regular and the only place I'm able to notice a difference is on long sustained braking efforts - IE coming down from Tokai mast chasing a KOM  .  Everywhere else they feel identical.  

[s14phoenix]

I had a random contamination that happened while out and riding.

 

I stopped at the garage to plug a puncture and pump the wheel - to find the puncture I used some of the soapy stuff on the window washing tray to check for bubbles and that went onto the rear disk and pads.

 

I battled to get it working but what did work was washing the pads in some rubbing alcohol and the disk too. Washing the bike did not fix the issue but the alcohol cleared whatever was on the disk and pads. Also did a light sand down...

 

Some even believe to set the alcohol on fire. just don't burn yourself or any other items in the process...

[HowardSteele]

I switched to Shim metal pads after going through 3 brake levers..2xt and 1 slx.The resin pads work great initially and then seem to loose their umph...you don't need the finned ones they are more cosmeteic at abot R120 extra ,your choice

[Bateleur1]

I had a another thread on noisy disk brakes (Shimano) not too long ago.  I was still going to follow some of the tips on it when I realised a couple days later that the front pads were finished.  So I went straigth for the replace all pad routes.  So I ordered the Shimano J02 pads as well and I actually replaced them last night.  Front brakes works wunderbar but the rear ones are from the start just as noisy.  I did clean the rotors before refitting the wheels and made sure I did not contaminate the pads with anything.  So I am slightly at a loss now.  Maybe replace the rotor?

[Mintman]

I had a another thread on noisy disk brakes (Shimano) not too long ago.  I was still going to follow some of the tips on it when I realised a couple days later that the front pads were finished.  So I went straigth for the replace all pad routes.  So I ordered the Shimano J02 pads as well and I actually replaced them last night.  Front brakes works wunderbar but the rear ones are from the start just as noisy.  I did clean the rotors before refitting the wheels and made sure I did not contaminate the pads with anything.  So I am slightly at a loss now.  Maybe replace the rotor?

 

That is strange. Interested to hear more from others on this. I also feel like my rear pads weren't contaminated. They also have 90% life left.

[droo]

Contamination and glazing are not the same thing. Contamination is from an external source, usually oil - you can contaminate pads by touching the rotors with your fingers.

 

Glazing happens when you don't bed your pads in properly - a few hard stops from a decent speed will sort them out. Find a hill, get up to pace, then without locking your wheels bring your bike back down to a walking pace as fast as you can. Repeat until the increase in bite starts to level off.

[Sepia]

  Maybe replace the rotor?

Rotors are easy to clean but pads, not so.

[Bateleur1]

Rotors are easy to clean but pads, not so.

 

I cleaned the rotors with methylated spirits and also wiped the whole brake assembly with clean cloth before inserting the new pads making sure I do not touch the inside of the pads.  As I said the front brakes work perfectly but even when rotating the wheels on the bike while on the stand you notice that the noise is still on the back rotor when applying the breaks.

[lechatnoir]

Glazing happens when you don't bed your pads in properly - a few hard stops from a decent speed will sort them out.

 

 

Sandpaper  remedies this for me.

[Bateleur1]

Had a look at this video.  Ironically I hear the same noise on his brakes.  Mine are just a bit louder.

[VroomSL]

Icetech rotors with metal fin pads - I've ridden consistently for 3 yrs, it lasts way longer. Once I experimented with resin fin pads - a waste of time it was.

[Christofison]

That is strange. Interested to hear more from others on this. I also feel like my rear pads weren't contaminated. They also have 90% life left.

Make sure your caliper is properly parallel with the disc. This is often the cause of the squeal caused by high frequency vibrations.

Make sure both pistons are actuating properly. If not, hold the one in while you squeeze the lever and then clean the sides of the pistons with an ear bud and some brake fluid.

Give the disc a light rub with some water paper and then re-clean.

 

To test if it is the pads that are contaminated, put the front ones in the back and see if that solves your problem.