I am sure we are all aware getting the new shimano 4pot 8120 brake pads is almost impossible
I run slx 4 pots with hope discs.
Looked at alternatives and went with uberbike race matrix (used before, fine) but they say 820 (i.e. zee/saint) on the back.
Uberbike swear there is only 1 specification of shimano 4 pot pad/cant print all models on the back so bought 2 pairs, fitted the set I needed on the back and bedded in properly.
They were super noisy (loudest squeeling ever) and fading so quickly. Checked disc and there was a slight ridge, so bought a new hope disc thinking thst could be the problem.
Again, bedded in religiously on the street and first run here we go again ,super noise, fading and seemed very grabby.
Disc is very discoloured so looks to have overheated (remember, brand new)
Uberbike claim pads are brilliant, steve peat used them, cant be an issue etc. despite there obviously being one.
So questions are. Is this a problem with race matrix pads? Do they not like hope discs? Are there sublte differences between the older and newer shimano 4 pot brakes and more importantly, where can I get some shimano, resin pads !!!
As per the new tradition, bump to get it seen.
I've had issues with hope disks and shimano brakes twice now. Can't really see why as its just a bit of steel, might just be coincidence, but I've got a mix of various brands of disks and had two hopes and two problems.
I’ve gone back to discobrakes after a few years of playing about with shimano, sram, Uberbike and others. I don’t think you can beat discobrakes quality v price tbh.
Been using Racematrix for years in all our bikes with no problems. Mainly Saints now with Guide RE on the Ebikes. A mixture of Shimano Rotors and Sram rotors on the REs
Thanks. For clarity the slx brakes and hope discs performed flawlessly with the oe pads, best brakes I have ever had (owned hope, shimano, fomula, avid etc) but I had to replace knackered pads.
Also new pads went on with the new disc.
I have fitted a semi metallic set now I had which seem silent but only tested on the street so will see how they go.
200mm rotor with a caliper spaced for 203mm perhaps?
isn't grabiness a sign that the brake is working effectively, and that you just need to relearn how hard to pull? all metalic pads are noisy (you may have had resin before)
Can highly recommend EBC pads. (Green). I was amazed to find some pads for my Tripster that don't honk in the wet. I'll always go for these in future
https://www.merlincycles.com/ebc-brake-disc-brake-pads-standard-99111.html
FA493 I believe, for yours.
can check here - https://ebcbikes.com/
Its a 180mm rotor. Been told Race matrix are resin based and shouldnt squeel.
Its not they are a little noisy, the volume is horrific! Much louder than bearable and very off putting going down a trail.
I fully suspect its a bad batch of pads, all other variables have been eliminated.
Found a set of old zee resin pads, fitted and so far no noise but going for a quick blast tonight.to check.
Uberbike have been very responsive and friendly, but not providing a solution (yet)
Pistons not pushed back properly / fluid slightly overfull - the new pads are dragging and overheating while the old pads are sufficiently thinner to come fully off?
Perhaps exacerbated by the Uberbike pads being fractionally thicker than the OEM pads?
That said, I took my gravel bike out last night for the first time in a while and the Race Matrix pads in that were making a shocking squeal, despite being only lightly worn.
Can't comment on the Uberbike pads but AFAIK they're right about there only being one shape of current Shimano 4-pot pad.
Try some of the cheap Clarks pads off eBay. I've found they work fine in my Zees with Shimano, Sram or no-name discs.
At the risk of topic deviation - Do the older XT finned pads fit the new 4-pot 8120's?
The fins are very different but the actual pads are same shape so yes, but bet they rattle like hell!
It looks like the uberbike pads are ever so slightly thicker and they are not a perfect mirror image of the shimano ones, the difference is tiny but might just be enough to cause grief...
Just need to stop using my brakes!
Just need to stop using my brakes!
My rear failed at Nant yr Arian recently. It was definitely less fun not using the brakes.
Its a 180mm rotor. Been told Race matrix are resin based and shouldnt squeel.
Its not they are a little noisy, the volume is horrific! Much louder than bearable and very off putting going down a trail.
I fully suspect its a bad batch of pads, all other variables have been eliminated.
Found a set of old zee resin pads, fitted and so far no noise but going for a quick blast tonight.to check.
Uberbike have been very responsive and friendly, but not providing a solution (yet)
Interesting... i'm on SLX 4 pots with Shimano disks (203/180) with uber race matrix pads. in the last few weeks i've started getting horrific squealing from the rear brake and the disk is quite badly discoloured like yours.
the good lady is on hope x2 with race matrix pads as well and has also just started getting the howling brakes as well.
never had this before with RM pads from uber and i've used them for years. The pads that are howling were bought at the same time so the theory about a dodgy batch is a real possibility.
I've had these brakes for a year and used a couple of sets of RM pads now so its definitely a recent issue
I bought some sintered pads from uber to see if that makes a difference.
Big fan on the Galfer Green compound on my E4s:
https://galfer.eu/bike/products/brake-pads/
(Galfer red is Hope standard fit I beleive)
Looks like they do the Shimano fitments too. Worth a look.
I got some Race Matrix pads a couple of years ago. Tried them with Sram Guides and XTR 2 pots. Slight increase in power over the standard pads. But any wet they scream for ages and loose power. When properly hot they also start screaming. Went back to Shimano resin and Nukeproof semi metallic for the Guides.
Are you using the pads for N03A type? i believe there's a couple of types but the SLX brake uses the N03A
Racematrix are the only pads I've ever thrown in the bin part-used. They were actually good in the UK, no complaints at all then I took them out to the alps and they just failed- totally unpredictable, grabby one minute, no power the next, some very scary moments. So I binned 'em, fitted my usual cheap kevlars, and got back to normal.
try sanding the disc surface.
isn’t grabiness a sign that the brake is working effectively
I fitted EBC Reds into Zee calipers on my Inspired street trials bike. Super grabby which is perfect for hopping on the rear wheel pretending to be a trials rider. Scared me though going at speed down a steep ramp to bottom of the cliffs. Soon get used to it though and adjust pressure applied through fingers.
Really interesting timing. I’ve used Race Matrix for years (Guides, X2 Hopes and shimano 2 pots) but recently fitted some to some brand new shimano 4 pots with new rotors. Bedded in and we’re fab for first couple of rides.
They have started squeeling horribly. I’ve tried cleaning the pads and rotors but still squeeling. This is a real pain as riding lots in the fells and don’t really want to draw attention to being there. It’s drier and dustier now then I’ve known it.
if you find a fix I’d really like to hear it…
Being Shimano, couldn't be the tiny leak of fluid getting on the pads? That makes em honk like a good'un
How could you tell if this was the problem?
Its def the pads. Changed to semi metallic pad and after it scraped the crap off the disc they are now silent and stop just fine.
I think the tolerances are smaller on the new 4 pots and as the race matrix are cheap for a reason.
@ChrisDavids can you e mail uberbike? They still claim non issue.
I’ll drop them a note as well.
Sort of glad it’s not just me…!
I use RaceMatrix, SemiMetallic and Kevlar pads from Uberbike in all our bikes, and have done for about 5 years now. Never any issues apart from the day eldest_oab was lapping Swiss DH track using his old MT5's...which would melt most brakes.
FWIW I find the Kevlar better for gravel/road and initial bite but they glaze more easily. We use RaceMatrix or SemiMetallic depending on what is in stock.
He has he M8120 brakes on new bike, Shimano OEM pads on Shimano 203 and 180 rotors in and is having them fade already on Stank Glen and today lapping Cathro's Pitlochry trail. He plans on Uberbike replacements.
I can report back on how he goes.
You could well be right about some movement of a pad - this would lead to squeal and perhaps lead to the glazing?
I have now emailed Uberbike. We’ll see what they say. As I say the many race matrix pads i use in all of my other bikes are universally excellent.
I mailed Uberbike.
The response was really helpful. They asked how I bedded in the pads.
I generally bung in a set of pads and do several hard stops then cool the pads down with a splash of water. I’ve also tried the technique the Santa Cruz mechanic used (there was a YouTube vid somewhere) he just got them wet and rubbed the pads together until the water ran clear.
Both these methods have worked, and I’ve been using RM pads for years.
Ubers method is a few gentle stops to conform pad to disk.
So following advice I’ve sanded back pads and disk and started again with the correct bedding in method.
Lasted half a ride. The noise is just horrible. I’m mystified as I’ve run race matrix pads for years with no issues, this batch is terrible,
Did anyone else having issues get a response??