SRAM Brake Scream !

[Rusty]

SRAM brakes are sub-standard and always have been.
Seriously, all it needs is a mildly humid day for them to squeal.

Running organic pads helps but not enough IMHO. A few bikes back I was determined to make SRAM work as the brake/shifter pod combination was so neat - and I was running bars about 380mm wide and needed all the space I could save. Machined my own spacer blocks and ran Shimano rotors. Was much quieter, but I could never get the feel I prefer so bought some ProblemSolver adapters and swapped to M675s. Bonus was no more Dot brake fluid.

 

[Zimmerframe]

SRAM brakes are sub-standard and always have been.
Seriously, all it needs is a mildly humid day for them to squeal.

Running organic pads helps but not enough IMHO. A few bikes back I was determined to make SRAM work as the brake/shifter pod combination was so neat - and I was running bars about 380mm wide and needed all the space I could save. Machined my own spacer blocks and ran Shimano rotors. Was much quieter, but I could never get the feel I prefer so bought some ProblemSolver adapters and swapped to M675s. Bonus was no more Dot brake fluid.

Presumably there's some intrinsic design problem if they're resonating/squealing (with loss of effectiveness).

I thought they'd magically fixed themselves yesterday .. 5km's in heavy rain .. not a squeak ! then the squeak began and wouldn't stop, even with riding the brakes for 40k to try and keep them dry.

Was just looking at different disk possibilities.

I thought by now I'd have stumbled across some info on someone cunningly using the sram levers (as they're neat) with shimano calipers (also change the fluid).

Tempted to try the organic pad test first before I start replacing hardware - though I'm still slightly on the fence as if that doesn't work I've gone down the usual route of trying all the cheaper bits before plumping for the more expensive route.

 

[Rusty]

@Zimmerframe It is a combination of things with the SRAM brakes. Over the years as Avid & now SRAM they have changed rotor design and rotor material but more often than not putting on a 3rd party rotor does help some, as does running organic pads but I have never found a combination as squeal-free as stock Shimano.
All brakes will squeal occasionally - often due to contamination from cleaning materials. You would be surprised at how a few micron sized spots of spray can drift around a room. Best way to use any spray is directly onto a rag - pointing away from the bike and even better a few meters away. If I get a squeal with Shimano brakes if I look at the pad under a microscope I will find some contaminant. Riding on the road it can be crap dropped from cars or if riding at Taupo can be volcanic dust that gets embedded. A careful rub with 1000 grade wet & dry will clean the dust but other contaminants take a bit more work.

Mix & matching SRAM & Shimano levers & rotors does not work as the SRAM system is a 2 pressure system while the Shimano is a single pressure. Also, once you have used a system with Dot brake fluid, changing to mineral is a no-no. The Dot fluid actually saturates the metal of the components and also the brake lines - this causes contamination of the mineral fluid.

Your best bet is to try organics. If you need harder pads instead of sintered you could always try Ceramics.

 

[Zimmerframe]

@Zimmerframe It is a combination of things with the SRAM brakes. Over the years as Avid & now SRAM they have changed rotor design and rotor material but more often than not putting on a 3rd party rotor does help some, as does running organic pads but I have never found a combination as squeal-free as stock Shimano.
All brakes will squeal occasionally - often due to contamination from cleaning materials. You would be surprised at how a few micron sized spots of spray can drift around a room. Best way to use any spray is directly onto a rag - pointing away from the bike and even better a few meters away. If I get a squeal with Shimano brakes if I look at the pad under a microscope I will find some contaminant. Riding on the road it can be crap dropped from cars or if riding at Taupo can be volcanic dust that gets embedded. A careful rub with 1000 grade wet & dry will clean the dust but other contaminants take a bit more work.

Mix & matching SRAM & Shimano levers & rotors does not work as the SRAM system is a 2 pressure system while the Shimano is a single pressure. Also, once you have used a system with Dot brake fluid, changing to mineral is a no-no. The Dot fluid actually saturates the metal of the components and also the brake lines - this causes contamination of the mineral fluid.

Your best bet is to try organics. If you need harder pads instead of sintered you could always try Ceramics.

Thanks @Rusty , that kinda of surmises the whole issue in a way even a muppet can understand and also covers some of the reasons why you can't really run sram/shimano combinations.

I've been procrastinating which pads to buy and also trying to match in with ordering other crap ..

Not sure if I should just go straight "organic" - of which some seem to also be semi carbon mixed, or carbon organic, which appears to just be a higher carbon quantity.

I've seen the "ceramic" pads. These are described as "quiet" but I don't know if this is just in the dry, or if they're better or worse than organic for "quiet" ...

As a totally out there idea before I try it and do an OTB 5m from the house .. has anyone tried running the metal pads without the springs in ? so they "float" over the disk and theoretically keep their temperature up - just .. ??

Just imagine you're replying to a child ... which you are doing ..

EDIT : the ceramic's I was looking at :

N&t SRAM GUIDE NOUVEAU CODE R code RSC semi Metallic Céramique Disque Fritté Patins de frein | eBay

 

[Mikerb]

Would it not make more sense to ask yourself why your brakes are squealing whilst others using the same brakes are not? Both of my bikes run the Guide brakes, both my mate's bikes also have the same brakes and it is very wet here in the UK at the moment...some trails are more like rivers. Neither of us have problems with squeal. Either the pads or rotors probably have some contamination...probably both since it will get transferred. So cleaning the rotors and changing the pads seems the easiest thing to do. Perhaps at the same time check the caliper alignment and that the rotors are true.

 

[GrandPaBrogan]

As already been said... on any trouble-shooting pathway, always start from the simplest (also usually the cheapest) possible solution... then work your way up.

Analogies: If this was a toaster, check if it's plugged into the wall. If this was a electronic device, do a re-start before considering any thing else.

For squealing brakes, it's pads first buddy... but only after doing a contamination clean-up (degreasing or light abrasive resurfacing).

BUT, it also pays to be methodical... by that I mean >>> only make ONE change at any time. Remember, it's a "process of elimination," so each time something doesn't solve the problem you can then move on to the next probable hypothesis.

Every time a remedy doesn't work, that's a win - because that points you to the next logical port-of-call in your journey.

If you make more than one change, or worse yet short-cut the entire process by changing every possible culprit you can think of - all in one go:
a) if it works, you don't know what fixed the problem, or
b) if the issue is still there, you won't know if any of what you've done could've worked if employed on its own, and
c) if a the first problem disappears but then a new unexpected problem appears, you won't know what caused it.

 

[Rusty]

As already been said... on any trouble-shooting pathway, always start from the simplest (also usually the cheapest) possible solution... then work your way up.

Absolutely

Analogies: If this was a toaster, check if it's plugged into the wall. If this was a electronic device, do a re-start before considering any thing else.

Kind of reminds me of a customer call earlier in the year.
Her - "My computer screen is blank, can you remote in and see what is wrong with it?"
Me - "I would, but as your screen is blank how can you tell me your access number and pass-code." Perhaps if you press the start button at the front for a few seconds to ensure your machine turns off, then press it again to start. It is possible your machine has hibernated and is not waking properly.

Her - "Tried that."
Me - "How about reaching around the back and pulling the power cord, waiting a few seconds then plugging back in again and trying a restart?"

Her - "Sorry, but I can not see which cable to pull out."
Me "It is the big one with a plug like a jug cord."

Her - "I KNOW THAT. The reason I can't see it is because the lights are off due to the power cut."
Me .... hangs up phone before I yell back at her. Charged client .3 hour for wasting my time.

For squealing brakes, it's pads first buddy... but only after doing a contamination clean-up (degreasing or light abrasive resurfacing).

BUT, it also pays to be methodical... by that I mean >>> only make ONE change at any time. Remember, it's a "process of elimination," so each time something doesn't solve the problem you can then move on to the next probable hypothesis.

Agreed, but SRAM are different from every other brand I have used.

 

[GrandPaBrogan]

Her - "Sorry, but I can not see which cable to pull out."
Me "It is the big one with a plug like a jug cord."

Her - "I KNOW THAT. The reason I can't see it is because the lights are off due to the power cut."
Me .... hangs up phone before I yell back at her. Charged client .3 hour for wasting my time.

Reminds me of a good friend of mine but on the opposite end of the scale - super genius fella... writes code and software. Retired in his late 40s - made it big, so no longer needs to work.

But in the early days, we were collaborating and designing a website that would appear and function similarly on both Mac and Windows OS. These days people don't even know that this was a huge challenge back in the early days. Tiredness, lack of sleep... he made a mistake so he bent down and pulled the plug out of the wall socket. Realising that that's not what he intended to do, and it dawned on him that he had just lost hours of code scripts (didn't save it)... he tried to fix the problem by hitting 'Command-Z' on his keyboard... over and over... while staring at a blank monitor.

I just witnessed a 2 minute mini-expo of the 5 stages of Grief and Loss - denial, anger, bargaining, depression and acceptance which came in the form of reluctant laughter.

 

[ryturn]

6 bikes 2 Reign's , 1 Liv Intigue , 1 Liv Hail SX and 2 2020 Levo's comp and expert.Everything bar the expert (Sram Code ) has Sram Guide various level Guide r, rsc and ultimates mainly run metal Sram pads , only 2 problems we have had is when carried on on towbar rack in the wet rotors got sound road contamination and squealed ,alcohol wiped the rotors all sweet again .2nd problem sticky levers a year back Sram replaced 4 sets.Maybe we're lucky we run Sram on all ,divetrains ,forks, shocks and brakes ,really good service through Sram DSD in Australia.

 

[Rusty]

To be fair @GrandPaBrogan - their server, monitor & router were on a big UPS and would stay up for over and hour to allow us to remotely shut it down to prevent database corruption.

Early days Mac & Windows? I used to code pure HTML with notepad open as well as a web browser - Nutscrape I think. Save notepad, refresh browser, correct mistakes, save and copy to server.
Much better when dual head adapters became available so I could have notepad on one screen and browser on the other.

 

[GrandPaBrogan]

To be fair @GrandPaBrogan - their server, monitor & router were on a big UPS and would stay up for over and hour to allow us to remotely shut it down to prevent database corruption.

Early days Mac & Windows? I used to code pure HTML with notepad open as well as a web browser - Nutscrape I think. Save notepad, refresh browser, correct mistakes, save and copy to server.
Much better when dual head adapters became available so I could have notepad on one screen and browser on the other.

I know nothing about code. I'm the graphic designer that kept pressing him for the impossible!

 

[GrandPaBrogan]

I don't have a squeal/honk issue on my bike. But I did have an irritating intermittent Zinging sound coming from the rotors. The brake system is a Tektro Orion 4 Piston set. Definitely not the pads or anything else other than the 203mm Tektro rotors would resonate every time it glanced lightly on the side of one of the pads while coasting.

I was able to solve the problem by changing over to Avid rotors (I already had those). Didn't touch the rest of the system, just the rotors. The Avids still glance the pads on occasion, but it doesn't zing. Resonance frequency is different.

If that didn't work, I would've tried the Shimano XT Ice Tech rotors next. The 6-bolt flange/spoke centre is aluminium with a steel rotor ring riveted to it. Aluminium should vibrate differently to the steel ring so they should cancel out their inherent resonant frequencies and act like a vibration damper - well, in theory anyway. I almost had wished that the Avids didn't solve my problem, because I really like the look of the XTs.

 

[Rusty]

Icetech rotors are what I put on but my bike had 200mm which is why I had to make some custom adapters.
I see SRAM has a similar rotor now

 

[KenX]

I'm thinking the reason some bikes squeal and some don't, irrespective of brake brand, is down to the harmonics of the rear triangle...........

 

[outerlimits]

I don't have a squeal/honk issue on my bike. But I did have an irritating intermittent Zinging sound coming from the rotors. The brake system is a Tektro Orion 4 Piston set. Definitely not the pads or anything else other than the 203mm Tektro rotors would resonate every time it glanced lightly on the side of one of the pads while coasting.

I was able to solve the problem by changing over to Avid rotors (I already had those). Didn't touch the rest of the system, just the rotors. The Avids still glance the pads on occasion, but it doesn't zing. Resonance frequency is different.

If that didn't work, I would've tried the Shimano XT Ice Tech rotors next. The 6-bolt flange/spoke centre is aluminium with a steel rotor ring riveted to it. Aluminium should vibrate differently to the steel ring so they should cancel out their inherent resonant frequencies and act like a vibration damper - well, in theory anyway. I almost had wished that the Avids didn't solve my problem, because I really like the look of the XTs.

View attachment 21105

How do you find the Tektro Orion 4’s ?

 

[Zimmerframe]

Icetech rotors are what I put on but my bike had 200mm which is why I had to make some custom adapters.
I see SRAM has a similar rotor now

I was looking at those yesterday, the centerline "X" only come in 140,160 and 180.

 

[outerlimits]

I’m looking at changing my SPAM breaks to Shimano Brakes. I have 200mm rotors. Anyone know if I can just use the SPAM mounts ?

 

[Zimmerframe]

I'm gona say YES ! ... just because somewhere down on my list where it says swap calipers .. it says use existing mounts because surely surely surely at least that much has to be the same !

Hope over fact always wins !

 

[outerlimits]

I'm gona say YES !

Hope over fact always wins !

I find if I keep trying I eventually stumble into accuracy. I do have Hope rotors, so I Hope they fit. ?

 

[Rusty]

I’m looking at changing my SPAM breaks to Shimano Brakes. I have 200mm rotors. Anyone know if I can just use the SPAM mounts ?

Not the times I have swapped. The shape of the SRAM calipers is different to the Shimano ones.

 

[outerlimits]

Not the times I have swapped. The shape of the SRAM calipers is different to the Shimano ones.

Oh bugger ?‍
So I may have to use Shitmano mounts and take 1.5mm off them. Lucky I’m handy with a hammer and chisel. I usually just measure with tape, mark with crayon and cut with axe. I thinking a finer touch is needed this time round. ?

 

[Zimmerframe]

Not the times I have swapped. The shape of the SRAM calipers is different to the Shimano ones.

Translation : Yes they will, but you'll have to use the angle grinder a bit and will benefit from having cool custom mounts which weigh less ..

This is quite amusing really. You think of all the threads where people hope that one day motor mounts might be standardised and here we are, 8000 years after the bicycle was invented and even brake adaptors are different ..

I'm thinking of ditching brakes until everyone sorts themselves out, things were much better before these new braked bicycles came along and started trashing trails.

 

[Zimmerframe]

I usually just measure with tape

Duct tape probably ?

 

[outerlimits]

Translation : Yes they will, but you'll have to use the angle grinder a bit and will benefit from having cool custom mounts which weigh less ..

This is quite amusing really. You think of all the threads where people hope that one day motor mounts might be standardised and here we are, 8000 years after the bicycle was invented and even brake adaptors are different ..

I'm thinking of ditching brakes until everyone sorts themselves out, things were much better before these new braked bicycles came along and started trashing trails.

I tried the whole no brakes on a a bike once. Went ok till I went down a big hill onto the “Shorncliffe Big White Pier” this pier is about a kilometre long stretching out into Moreton Bay, and made out of all timber.
Put me feet down wearing double pluggers to slow down and a pencil sized splinter went 3 inches into my foot.

Now I just find it easier to use brakes.

Duct tape probably ?

Yeah but I marked measurements on it with a crayon first ?

Non Aussie’s may have to google some of the stuff I said for it to make sense, and maybe some Aussies too ?

 

[Tamas]

Icetech rotors are what I put on but my bike had 200mm which is why I had to make some custom adapters.
I see SRAM has a similar rotor now

"Custom adapter" Why??? I just put regular 6mm washers under the caliper they are exactly 1,5mm thick which is exactly the difference between the radiuses of 200 and 203...

 

[GrandPaBrogan]

How do you find the Tektro Orion 4’s ?

They're OK. Entry level... nothing to complain about if taken in that context, but nothing much to brag about either.

The levers can be adjusted to engage at your desired distance away from the grip, via a small allen key that rotates the tiny plunder rod - pretty basic. However, the lever doesn't have an adjuster to limit how far backed-out it is. I can live with it, but I'd like the levers closer into my finger reach so I don't have to pull as much when I stop in a hurry. (Less lever throw).

It uses mineral oil (same as Shimano) so if spilled, it's pretty safe and doesn't eat painted surfaces like DOT fluid can do. Under applied lever pressure, it feels just a wee tad towards the spongey side but not bad.

The 4-piston calliper doesn't feel progressive. The two pistons on either side of the caliper just moves out at the same time - just to apply an even spread of pressure against a wider brake pad profile. It feels that way too (like a 2 piston unit)... maybe that's why it has a slight softness at the lever feel, otherwise it won't have any modulation. It's plenty strong enough, but I wouldn't say it's for racing. For what I do, it's perfectly adequate and I'm not wishing for something better.

--

Back in 2006, I bought a free ride bike with possibly the earliest Avid CODE 4-piston brake kit (before they became SRAM)... I still have the bike in storage. If I pulled hard with one finger on that it will lock-out a Maxxis HiRoller even on pavement. Depending on where you put your butt beforehand, it'll either flip you OTB or flat spot your tyre. At first it's terrifying, but then once you get used to it's power and adjust your finger pressure (just light pulls), it's very very controllable and the modulation is superb. If you look at the two halves that make up the caliper block, they are held together by four bolts (the Tektro only has two). I could be wrong about this, but I was always under the impression that the pads are pressed by only two pistons to begin with, followed by the other two (in fact I'd laugh if there were 6 pistons in there - I've never opened it to find out). It's always been my benchmark when it comes to brakes. I guess I mentioned this because my appraisal of any brake system is always going to be tarnished because of how much I love this thing.

 

[Zimmerframe]

Put me feet down wearing double pluggers to slow down and a pencil sized splinter went 3 inches into my foot.

You're just such a glass half empty kinda guy ! rather than "That's lucky, a handy piece of kindling".

 

[Zimmerframe]

It's been a couple of weeks since I tried the cleaning and sanding .. so as we're starting from "simplest" again .. I thought I'd give it another go and be a bit more thorough ..

Started with @GrandPaBrogan's minimum contamination system, stripped naked and used White Vinegar to clean the disks .. Quite impressive what came off when you consider I cleaned the bike yesterday.

Right cloth, both sides like that, first clean. Left cloth, both sides, second clean ..

Vinegar is your friend ..

@outerlimits & @Rusty probably uses it as a nice after dinner digestive as they chat on Skype about the good old days of cast iron frames..

Stripped and cleaned the pads and calipers. Sanded the disks and calipers with 150 this time instead of 800 last time.

So will go for another drowning session later, try to bed them in again and see how we get on.

 

[GrandPaBrogan]

Vinegar is your friend ..

I distinctly remember that I suggested to clean your rotors... not marinade them!

Hope it works out!

 

[slippery pete]

Would I be mad to think I could keep the SRAM levers - and change to Shimano calipers .. I know .. I'm being mad .. couldn't possibly use the same pipe could they .

The pipe is not the problem. SRAM uses glycol DOT fluid and has DOT fluid compatible seals. Shimano uses mineral oil and has mineral oil compatible seals. Mismatch of fluid and seal will cause swelling, disintegration and brake failure.