2 Reasons Why Your Disc Brakes Don't Work

Jun 13, 2017
by Vernon Felton  


“So you just grab the rotor and push it towards the pad that’s dragging…”

“Wait,” I have to stop Jude right here. I’m sure he’s giving me a load of crap. “You grab the rotor? You’re kidding me, right?”

The one thing everyone knows is that you never, ever touch your brake rotors. Doing so can transfer oil from your fingers to the rotor and from there, inevitably, to the brake pads on your disc brake, which, in turn, leads to weak braking power. So, surely, Jude Monica is feeding me a line of bullshit. We are drinking beer. In a bar. It would stand to reason.

Jude, however, is completely straight-faced.

“I’m 100 percent serious. I mean, you wash your hands first, of course, but you can use your rotor as a tool to stop your pads from rubbing the rotor. Really.”

Here’s the thing: Jude Monica knows disc brakes.

Disc brake tips with Jude Monica
This is Jude. He's been on the road, wrenching and preaching the gospel of hydraulic disc brakes since 1998.

The guy has been working on them, as Magura USA’s technical service manager for…well, since roughly the very dawn of time. The guy lives and breathes disc brakes, which is why we’re sitting at the brewery, post-ride, talking about them—or specifically, talking about the two most common complaints he hears from mountain bikers while he’s out on the road: (1) My disc brake suddenly started rubbing in the middle of a ride; And (2) My brakes don’t have air in the lines, but they aren’t stopping with the same force anymore.

The grabbing a disc brake rotor thing, however, had me flummoxed. So I had Jude demonstrate it in the video above. My Blair Witch filmmaking style notwithstanding (video production has a steep learning curve), it’s worth watching to see how Jude gets the job done. But I thought I’d add a bit of context here as well.


Disc brake tips

An Interesting Perspective on Rotor Rub

There are plenty of reasons why your rotor may begin rubbing against the brake pads. Maybe you completely taco’d the crap out of your wheel…that’s always hard to miss. Or perhaps your rotor has warped. Or maybe you never set up your disc brake caliper correctly and the rotor has been rasping away since day one.

But we’re not talking about those situations here.

I’m talking about that moment, mid–ride, when your rotor suddenly starts rubbing consistently against one of your brake pads. By consistently, I mean a constant, slight dragging against one of the brake pads. If it’s an intermittent rubbing, it probably signals a bent rotor and, well, it’s time to either true the rotor or cough up the cash for a new one.

So in this case, let’s assume your rotor has begun a constant slight rubbing against one of your brake pads. If you’re like me, you probably rectify that particular problem by loosening the caliper’s two mounting bolts and realigning the brake caliper. It works. Jude, however, suggests that this approach often misses the point. After all, it’s not as if your caliper suddenly moved during the ride—those two bolts do a good job of keeping it rooted to your frame. What has shifted, however, are the pistons’ placement inside that caliper. The pistons, Jude argues, are what you want to manipulate—not the entire caliper body—and you can use the rotor to help you do that.

Disc brake tips with Jude Monica

If you’ve ever removed your wheel and pulled the brake lever (bad idea, of course), you know the pistons and pads will advance into that rotor-less free space within the caliper and then you’re stuck having to pry the pads apart again.

Well, when you’re riding and you're cornering, your front and (especially) rear wheel can be shimmying about, from side to side, a hell of a lot more than you might suspect. Monica argues that your rear rotor can flex as much as 5 millimeters from side to side during a hard cornering moment over rough terrain (this varies depending on axle, wheel and frame stiffness). Anyhoo, if your wheel and rotor are shimmying from side to side during these micro-moments and you hit the rear brake, one of your pistons might be able to advance farther than normal. It advances and then it stays there. You get through that corner or really rocky bit of trail and, crap, now the rotor is constantly dragging against the pads on that side of your caliper.

Disc brake tips with Jude Monica

Again, you can solve this issue pretty easily by re-centering the caliper itself, but Jude’s approach is to simply reverse what happened on the trail. He does that by determining which side of the caliper (inboard or outboard) is getting the rotor rub. Then, after wiping his hands on something clean, he pulls the rotor into the rubbing pad with one hand, then pumps the corresponding brake lever with his other hand. Doing this helps re-center, as it were, the pistons themselves within the caliper.

This procedure is not an exact science—Monica readily admits it’s more of a finesse move, but I’ve seen him do it and, yeah, it works on every brand of disc brake. Again, the guy has worked on more brakes than most of us have ever seen, so he didn't pull this maneuver out of the ether or his backside. It sounded crazy to me, but if you think about it, it actually makes sense. Or maybe it doesn’t make sense to you, in which case, just watch the video.

If, like me, you still freak out if someone gets within a few inches of touching your brake rotor, you can always do the rotor-grab maneuver while wearing clean latex gloves.


Disc brake tips
Less glazed, more worn...either way it was time for a change. Don't judge me.

WHEN PADS GO BAD
A loss of braking power is usually the result of one of two things: air in the system or contaminated/glazed/worn brake pads. Air in the system is pretty easy to diagnose. Straddle your bike and, with the bike stationary, pull the brake lever. If the lever simply sinks to the handlebar, you’ve got air. If, however, you can feel the pads contact the rotor in the usual spot in your lever throw, you’re probably not dealing with air bubbles in the system. Instead, it’s probably your pads.

Pads are, no big revelation here, what brings friction and stopping power to the party. If your pads are glazed over, excessively worn or contaminated by road gunk, grease, oil, something-evil-and-slippery, you might as well be squeezing a couple of ice cubes against your rotor for all the good it’ll do you.

Maybe somebody (certainly not you, right?) tried to lube your chain with an aerosol lubricant and wound up dousing not only your drivetrain, but also your brake pads. It happens. For that matter, sometimes your pads pick up contaminants while your shuttling to the trailhead and your bike is riding on a hitch rack—crap sprays up from the road, gets on your rotor and—voila—you hit the trail with a honking brake that has gone weak and grouchy.

Disc brake tips with Jude Monica

So, remove your wheel pull the pads from you caliper and take a look at them. If they are excessively worn (there’s less than 2.5 millimeters of pad left), toss them and get some new ones. Unevenly worn in a big way? Replace them and realign your brake caliper. Still plenty of pad material, but they are slick and glazed looking or darkened by some mysterious substance? We can work with that.

I’ve always used a rough (100) grit sanding paper, but Jude Monica recommends a sheet of drywall sanding screen (readily available at hardware stores). The mesh will rough up your pad nicely (giving you back your grip and bite) and, best of all, the layers of pad material you sand off will fall away through the sanding screen—so you aren’t just rubbing contaminated brake pad powder back into the pad itself. Nice. Jude recommends rubbing the pad in a figure eight pattern, to get an even sanding. You don’t want to take off much material here at all. You’re just scraping off the crappy surface layer.

Disc brake tips with Jude Monica

Put your freshly surfaced pads back in the caliper where they belong. Before you toss in your wheel with its contaminated rotor, clean off the with a clean rag or paper towel soaked in isopropyl alcohol. If you’re persnickety (I am) use latex gloves. You’re going through the effort, you might as well do it right. To that end, some people skip the alcohol altogether in favor of automative disc brake cleaner. That stuff is nasty, but it works great. Definitely bust out the gloves and gobbles when you're using that stuff and do your best to not huff it, as I believe the label clearly states the fumes will eat holes in your brain. I think. It's nasty, we'll just leave it there. At any rate, once the rotor is clean and has had time to dry, slap the wheel back in. You’ll want to re-bed in your brake pads to get optimal performance out of them (that’s a topic in and of itself), but either way you’re going to be a hell of a lot better off than when your pads looked as if they’d been coated in Teflon.


245 Comments

  • + 524
 Me: 'Rotor is dragging'
Mate: 'Stand back, I read this article on PB'

Melts fingers on brake disc.
  • + 40
 Just spat my coffee on my laptop.
  • + 2
 Memory in
  • + 0
 Cant fix stupidity.
  • + 43
 I have definitely touched a rotor after a long decent to see if it was hot... And that's the last thing I felt in that finger tip for a week... Ahh to be young and stupid....
  • + 7
 That made me laugh! I've been branded by my rotor, way back when I was just starting to ride DH. Good times.
  • + 0
 Yu, sir, have won the internet.
  • + 7
 Some sort of rotor covers need to be made for those of us that drive alot to ride with hitch mounted bike racks. I've had several instances of contaminated brake pads from driving on wet roads.
  • + 16
 Well according to the UCI disc brakes on road bikes will do that by merely looking at them.
  • + 5
 @FreshKirk: plastic bags?
  • + 2
 @FreshKirk: I use plastic over shoes, they're a small plastic bag with elastic opening and work perfectly.
I use them at work for showing clients around new houses.
  • + 0
 @FreshKirk: NO. Only roadies need rotor covers.
  • + 10
 Are you even a mountain biker if you dont have a rotor burned into a calf?
  • + 2
 @rclugnut: Just spit on it!
  • + 13
 @ryanthedestroyer: that's what she said
  • + 3
 @rclugnut: My mates brake caught fire after 60kmh down a fire road and there were flames and smoke!!
  • + 1
 @rclugnut: I started feeling mine after two days. (On the other hand, my leather glove I was wearing still has a hole).
  • - 3
 @rclugnut: Yung, dum, and full of cum.
  • + 1
 Ha!! No comments on Formula. SQUEEEEEEK!!!
  • + 147
 1st reason: You have Avid Elixir so they have been designed to fail from new
2nd reason: You have Sram (we changed the name but not the quality) Guides so the modulation will be lovely until you actually need to stop your bike. The shudder judder on the front brake is actually designed to let you know that your brakes are on, like the bumps on a road before you reach a roundabout.
  • + 2
 hahaha
  • + 53
 Explains why Sam Hill was so fast in Val Di Sole in 2008 Also explains why he crashed at Val Di Sole in 2008
  • + 20
 Your avid/sram brakes work - congratulations your brakes were built on either a Wednesday or Thursday
Your avid/sram brakes don't work - unlucky your brakes were built on any other day.
  • + 11
 But... but... the bike media keeps raving about the new SRAM Juicy
  • + 10
 @shakeyakey: lol I had some on my old Anthem. Could never understand the hate. But I must have got lucky with a Wednesday set.
  • + 9
 @shakeyakey: The front brake on my DH bike must have been a Wednesday build. A cheap Elixer 5 that grabs harder than a pissed off gorilla. So much so, that I can't bring myself to change it like I did the rear. I've never even bled them haha.
  • + 6
 perpetuating the myth .or get someone else to set up your brakes you obviously cant
  • - 6
flag DHaddict82 (Jun 13, 2017 at 7:28) (Below Threshold)
 @shakeyakey: lol. Mine must have been built on a Wednesday. 7 year old guides. Still strong.
  • + 37
 @DHaddict82: guides haven't been around that long......
  • + 2
 @BorisBC35: The higher end models like the XO were fine. I think the "taperbore" design just really sucked with the cheaper models that had less-specific tolerances like Elixer 3, 5, 7 that came OEM on like a billion bikes.

I've had 3 pairs of Guides and I like them a lot. They seem more powerful than Shimano, but Shimano is definitely easier to bleed when the time comes.
  • + 1
 I had a few Wednesday sets which were awesome but I did have a couple Friday afternoon sets Frown
  • + 3
 @jeremygosse: oops!!! Sorry they are Codes!
  • + 1
 I have the elusive indestructible Juicy as the front brake on my P.2 ... Almost ten years now and it still works flawlessly, not even bled once. The rear one has failed quite spectacularly soon after mounting it through.
  • + 69
 #veebrakesaintdead
  • - 12
flag Kramz (Jun 13, 2017 at 1:01) (Below Threshold)
 Honestly, often the simplest solution is the best. I would rather be the person that can pick up a rock, than the person who has to rig/manufacture a pully system.
  • + 2
 Honestly - I'm poor Simple Solution - sell body Nope, your theory is flawed
  • + 8
 #bringbackdrumbrakes
  • + 65
 "If they are excessively worn (there’s less than 2.5 millimeters of pad left)"
How thick are your pads new?
  • + 13
 exactly, that surely is a typo? I replace them when there's about 1 mm or less.
  • + 55
 @jose90: pad springs actually do brake!
  • + 3
 same here. i dont think mine have much more on them when brand new.
  • + 4
 Must be superstar ones but don't worry after completing quarter of the figure of 8 you'll be down to 0.000000001 pad left
  • + 51
 It's like the HP Printer cartridge monitor. Replace when less than 90%.
  • + 11
 That's 2.5mm including the backing plate.
  • + 16
 not enough enduro bro! i replace them when the sparks start coming out.
  • + 6
 @trauty: Best comment of the month !
  • + 2
 @jose90: i replace them, when I can use them as racor blades
  • + 1
 The twin piston pads start around 3.95mm each side and the 4 piston pads start around 3.60mm each pad including steel back plate.
  • + 1
 @shakeyakey: It takes quite a lot to remove material this way but when in the caliper being used, heat is what accelerates the wear.
  • + 1
 @zutroy: Correct! Nice Zutroy!
  • + 45
 To be fair I have to thank Sram for everything I know about disc brakes. bled my old avid elixirs so many times (until I finally realized I wasn't the useless here) that I've become an expert. Thanks Sram
  • + 5
 Same here ! Thanks Avid !
  • + 3
 LOL, well said. They definitely force you to go through all the possible culprits to solve issues with the brakes.
  • + 1
 Yep... 1) Arrived in Mammoth with the front Elixir locked solid, probably related to the altitude change. Cracking open a bleed port cleared it up. 2) A used S-Works Epic came with "Red XX"- they weren't working right, found out it was a widespread problem. SRAM said they'd send an upgraded "innards kit" for free...it would take 2 months because they were on national backorder. A sympathetic parts person sent me a set from her private reserve. I got them working but really solved the problem by replacing w/ Formula R1's. 3) My new Mach 4 has Guide Ultimates (praying) !!

I guess SRAM and I have some dysfunctional codependency thing....
  • + 44
 2 Reasons Why Your Disc Brakes Don't Work:

-You don't use HOPE brakes.

-You don't use HOPE rotors.
  • + 7
 Not called hope for no reason. Better hope they work!
  • + 0
 Bang on mate!
  • - 2
 I like hopes in every way except they just don't have enough power. The v4 is ok but no better than xt regarding power but 3 times the price. But they are easily the best looking with the best materials used. Just shame on the power.
  • + 8
 @bonfire: 18 months ago I copped some Tech 3 E4s for a build. Haven't bled them since initial setup, still grab like magic.
  • + 3
 @mikelee: You have to properly bed the Hope pads and rotors. It's kind of a pain in the arse to do, but it's how you get the power. If you just slap them on and hit a long downhill, you glaze the pads because there is no pad material of the rotor to grab. I skipped the bedding (too impatient to just go ride) the 3rd set of Hopes I bought and they had about half the power of the previous Hope brakes. Even the X2's with a 183mm have more than enough power. I'm super fat and run M4 and E4 and have zero issues stopping. Taking 20 minutes to bed them makes all the difference.
  • + 5
 Seriously though, why is Hope the only brand smart enough to use floating rotors? The entire situation described in the article (rotor moving 5mm during turns, pads become misaligned) wouldn't mean much if the rotor itself could move 5mm in its mounts.
  • + 1
 @WaterBear: honeslty, the only complaint I have with Hope is their floating rotors. The rivets keep coming loose after about a year and make the most annoying rattling sound. Its happened with 3 straight rotors
  • + 2
 @sooner518: That is a disappointment. My old motorcycle had floating rotors (which never gave me any trouble) and I always wondered why we don't have them in MTB, where rotors warp even more easily.

Trying not to rant about how we've got Boost and 12 speed but not any dad-gummed floating rotors. Garsh durn it.
  • - 1
 @oldschool43: lol I've been riding 20 years mate! I know how to bed in brakes!! I've had the original c2,pro,v2,e4 and v4. Like I said beautifully made with adjusters that actually work. But for me they all lack power. An xt is stronger than the e4 and saints beat the v4. I like to brake late and very hard so I need lots of instant power as opposed to modulation. Everyone's different though. They're still top brakes but for me I'll stick with shimano for price and performance.
  • + 1
 @sooner518: Strange. I just had my original Hope floating 160mm rotor rivets get loose. I have had it for 6 seasons, maybe 5,000 miles on it. It is considered a lightweight rotor. I checked my other ones, no issues. The front 183mm rotors are thicker. I've only used floating rotors for the past 6 years, no issues other than this one. I have 8 on 4 bikes. I don't do trials and only use 160mm on the rear and I am a heavy front wheel breaker and don't skid. They work better than the fixed rotors. And in cold weather it's awesome. They pop as they cool if you stop at the bottom of a long downhill. And they match my bikes and hubs Wink
  • + 1
 @mikelee: That's cool. I have a friend that rode my bike, he has XT and didn't like mine. I rode his and didn't really like the "on off" nature of it, but could work with it, just had to change my style. Most people that try Hope skip the bedding. I skipped it once and they barely worked, so I get why some people think they don't work. The floating rotors have tooling fluid residue on them too. I clean them first, then bed them.
  • + 6
 @WaterBear: if you want floating rotors, and you know Hope make floating rotors, you could just...umm....err...ahhh...nope, never mind, no solution to that problem, complain away.
  • + 1
 @dsut4392: You just can't help some people dude. Thanks for trying though!
  • + 1
 @oldschool43: to each their own. Tbh all brakes are pretty solid these days. It's just personal preference. The v4 have good power but the money is crazy compared to saints. Even though they are a lovely looking brake. Good to see Americans buying British products anyway????????
  • + 2
 @oldschool43: those question marks should be a thumbs up emoji! Haha Guess they don't work on here yet.
  • + 2
 @mikelee: Haha.. Gonna love this then. All 3 of my current bikes, 2 Cotic's and an On-One, have Hope hubs, headsets, brakes and seat binders. Renthal stems. One bike has Halo rims. Tbh, I've had zero issues with UK products. I've saved $1000's compared to US made. Even the overseas made US frames are $200-$300 more for the equivalent. The orange man will likely change that and it could cost more for UK products some time soon. But you Brits make some really good, affordable stuff. Smile
  • + 1
 @WaterBear: Floating rotors are the best for performance but they A) are expensive to produce B) rattle so cause concern (unnecessarily!) C) are heavier
In addition, they may not be the solution to keeping the caliper piston situated as they will also push the piston/pads around just as easily.
  • + 1
 @rjude: Uhm, they are actually 4 grams heavier (that's knickpicky) and they do not rattle, at all. If they do rattle, they are dangerously worn and should be replaced. Hope says "1mm of play". That's not exactly loose. Again, I have 8 floating rotors and just had the first 160mm rotor (considered light weight, which IS lighter then a one piece Hope 160mm) wear out after 6 years and 5000 miles. They are slightly more expensive. As for moving pads, I'd say they don't push pistons as easily as a fixed stainless rotor. The aluminum center section it stiffer than a one piece (on a 183mm), but the outer stainless piece is more pliable. Kind of thinking you have never used a Hope floating rotor. I've had floating motorcycle rotors make noise, but even my "loose" Hope rotor doesn't make noise under normal use.
  • + 1
 @oldschool43: Thanks olschool43. No, in fact I'm a believer in full floating rotors and use them on my moto race bikes...all of them. They are a far better performer.
Magura use to make full floating rotors for the original Gustavs but people would freak out at the rattling.

BTW, when they get play it is no concern at all from a danger concern and is how they work properly by allowing the friction area to expand and contract without warping the "carrier."

I like them a lot!
  • + 23
 A sticky piston is so often the cause of my brake rubbing. One stays out further than the other, you adjust the caliper to correct just like above.. nothing good happens. Keeping the pistons clean and free-moving is the most important part of brake maintenance.
  • - 2
 That's happened to the front and rear brakes on my bike. Visible rust on the pistons. High quality SRAM Guide R's FTW.
  • + 4
 @Highlander406: DOT fluid might have better thermal properties than mineral oil but it will corrode your brakes as soon as there is any exposure to air. I had an old pair of Elixirs that corroded so badly that the nut holding the line in the brake lever crumbled when I tried to unscrew it.
  • + 2
 @WaterBear: Shimano keeps the corrosion off. Ti bolts don't rust.
  • + 0
 double post
  • + 24
 My Dad once de-greased his pads with WD40.............
  • + 6
 @AlexS1: windex, man...it's windex.
  • + 5
 I met a guy that was sick of noisy brakes as well and oiled them properly with wd-40... no sound in the brakes anymore though
  • + 18
 I was told to copper grease my squealing pads when I was a noob. Guess what side I greased...
  • + 1
 I bought some dot 5 brake fluid thinking it would cure my squeaking avids... It didn't work.
  • + 3
 And put it on my rotors. (Kind of a crucial detail)
  • + 1
 @ibishreddin: surprised and glad you are still shreddin!
  • + 17
 I've often found literally caking the whole brake (disc and caliper) in good quality British mud and dirt then giving it a few hard downhill applications cleans them up nicely then rinse off with water. ;-)
  • + 9
 Seasonal brake maintenance regime (or Winter as we call it).
  • + 22
 @fartymarty:
I thought the UK only had two seasons ?

Rain and Less Rain ?
  • + 24
 @Waldon83: We have a 'more rain' season too
  • + 12
 As the guy that does the bulk majority of brake bleeds at my LBS, I've pretty much given up on anything Avid, or old Hayes. At this point we use the 300 series Shimano to replace them. I think they're $69 retail and I can typically install them in less than 10 min, and if you do it properly, you don't need to bleed them afterwards.
Personally, I've had incredible luck with MT5 Maguras they are bleed free if you install them correctly, and I don't think I've ever had better power or modulation. My newest build I considered going with Zees, but after a long weekend of riding my MT5s, I ended up going with them again. (also, the MT5s with my shop discount were half the cost)
  • + 10
 If you want mechanical disc brakes go Avid BB,
If you like to ride all the time and you aren't too fussy about setup (set and forget). Go shimano.
If you like rare stuff and like to play around with your setup (idealy more than riding) go Hope, Magura, Formula...
If you love troubleshooting and spending time in your garage, go Avid hydraulic.
Simple as that.
  • + 13
 Yet another ground braking article!
  • + 6
 braking news!
  • + 29
 Just stop.....
  • + 0
 Your braking my heart
  • + 38
 We've not seen puns of this caliper for a while
  • - 2
 I didn't change my pads because... ...it wasn't on the rotor!
  • + 12
 @graeme187: ...I know eh...what a drag
  • + 2
 They're just padding out this article...
  • + 4
 They've written a piss-ton of articles about this recently!
  • + 9
 These puns are bleeding me dry!
  • + 6
 we over lever these brake puns so much it is beginning to piston me off
  • - 3
 these puns are starting to cause some friction. we better pump the brakes.
  • + 6
 you gotta be skidding me, these are terrible
  • + 11
 "2 Reasons Why Your Disc Brakes Don't Work"


1/ you own SRAM/Avid brakes

2/ you drag the brakes and glazed the pads
  • + 9
 Since moving to Shimano (Saints and XT) I have had way less issues with my brakes. They are by far the easiest to set up as the pads and pistons retract to give a decent amount of play.

I've had Hopes and Hayes before and Shimano are a million times better. Plys they use mineral oil so no more brake fluid.
  • + 7
 Loving the Avid/ Sram hate! They really do suck!
  • + 2
 @Braddlie: FFS - I've just bought a set of Guides to ditch my Deores. Frown
  • + 8
 @pimpin-gimp: f*ck the haters man.

I had Trail XO's and now Guide RS's.. absolutely bang on and I haven't bled them in 3 years (I prefer a spongy feel)

Shimano are sick, don't get me wrong. But they do bite a bit too quickly for the feel l like. It's like once the lever throws over the cam, BAM it hits you. Again. Very powerful.. but not my personal preference.

My Girlfriend has Hope Tech Evo 2 pot and my got those bastards are powerful. So I don't understand that hate toward them.

Bad news always travels faster it seems
  • - 5
flag petrospit (Jun 13, 2017 at 3:43) (Below Threshold)
 @pimpin-gimp: Biggest mistake you have made. Deore as far as modulation goes is the best brake out there and they have decent power. i use one finger with a 160mm rotor
  • - 2
 @steviestokes: Im not a hater, its through using Avid/ Sram brakes Iv grown to hate them! They are the hardest to blead! But they are the lightest brakes you can buy!!
  • + 2
 @petrospit:
1 finger and a 160!
you must be 50kg with a ripped 49kg finger
  • + 3
 @Braddlie: guides are not hard to bleed... If you are finding that you are doing something very wrong. Elixirs on the other hand fml
  • - 1
 @Jokesterwild: never run Guide brakes! Im referring to the XO trails i had on one of my DH bikes! And the Elixers I had on my trail bike! I run Saints for DH now, never looked back easily bleed saying that the levers are a bit soft! Zees for trail ????
  • + 3
 Yes, the SRAM/Avid brakes suck no matter how many times their marketing renames it !!!
  • - 2
 @will-burr: have fun with your light switch brakes I'll enjoy modulation...
  • + 1
 @steviestokes: fair dues, I loved my old Elixir SLs off my old enduro, I hope the Guides are as good. Never got on with shimano brakes.
  • + 1
 @pimpin-gimp: I really like them. I run my lever close to the grip, and they feel wicked. Again.. Shimano's are constantly brilliant, but even they get sloppy levers from the master cylinder sticking now and again.
The old cheaper Juicy's and Elixirs.. had piston problems.. but I think they area lots better now! And yeah.. 3 years without a bleed.. I almost feel I Owe it to them to bleed them, even if it makes no difference at all! haha
  • + 1
 @fartymarty:

Same - I bet the Hope camp will dis on my going Saints, but XT & Saint is all I've had since V-brakes died, have always been great to me.

I was either taken by propaganda or it really works, but I run the sintered metal pads, never saw pad material mentioned in article. Propaganda?
  • + 1
 @steviestokes: yeah, Avids are awesome till thry need the first bleed. They are sort of disposable items - once they fail, chances of a repair are slim. Though I heard Guides are better in this regard, but this was definitely true for Juicy, Code and Elixirs...
  • + 5
 All the people screaming about touching the rotors with clean hands must go riding in some sort of sterile bubble cos I can assure you if your riding in the real world there are worse things than a set of clean finger hitting your brakes as you ride along. Plus if you do this just wipe the rotor down afterward with brake cleaner if your that worried. My brakes
  • + 1
 Exactly! Good comments.
  • + 5
 If shimano brake pads sit unused for a long time, they seem to absorb water out of the air or something. It's really weird. Brand new, unused brakes make noise if they sit for too long.
  • + 2
 Yeah, I get this too if a bike sits over winter. Maybe the pads oxidize on the surface. After a few rides it goes away though, so either the surface oxidation wears away, or a few heat cycles removes the moisture from the pad.
  • + 1
 @axleworthington - is that the sintered metal ones, or the organic compound (no clue the 'compound') - I was told & do run the sintered metal ones since I'm in WA, was told wet enviro mattered.

Mine only do a quick squeal when wet, dry for storage & I can pull it out & quiet if it hasn't seen a puddle before I pull up on the brakes.

--Do you know if the pad compound is a legit thing? I don't - I honestly went off an article here on PB I think.
  • + 1
 @Seven-iron: my experience with sintered Shimano is that they need to be bedded in again if you didn't ride them for a while. Never had that with the organics. The organic pads start off really strong, but they fade quickly. Sintered get even more bite as they heat up, perfect for mountain biking.
  • + 1
 You might be running into this issue

blueliquidlabs.com/repairs/solving-that-brake-squeal

TLDR;

The stock o-ring between the two calipers halves can leak in cold weather, or just over time due to shrinkage from temperature, or machining tolerances on the o ring groove. You can replace it with a harder durometer version and solve the problem
  • + 7
 I definitely recommend a set of avid elixir's, you'll ride a lot faster believe me!!
  • + 3
 my Shimano Zee are really temperamental: they would work great one day and underperform the other. Funny thing is that the front brake tends to be more whimsical: after a couple of days of not riding the braking power goes to 30% of the full power and it only gets back after a full run. I use standard pads that came with the brakes (I believe sintered) and tried each and every method of decontaminating the pads/rotors: alcohol, sand paper, blow torch etc. When they do work, they're good but after years of hearing people say Avid is lemon I expected sth better
  • + 20
 I feel the need... the need for brake bleed.
  • - 1
 sounds like lazy/stuck piston(s)
  • + 1
 Same issue here. Bikeradar has also found similar. I think the pads absorb moisture. I find a light sanding and a squirt of brake cleaner sorts them out. The wandering bite point was more of a problem.
  • + 5
 It took me a long time but I eventually got them working perfectly. No more power loss, no more drastic changes in bite/grab while riding. Even after the bike sitting all winter I still had 100% power.

1) Sanded and baked the pads in the oven. I've found all Shimano pads easily glaze. Propane torch worked on my XT's but my Zee's needed to be baked. They eventually glazed a bit after months of riding, a quick sanding fixed this.

2). It's extremely difficult to get the air out from behind the pistons. A little bubble can get stuck in there. I was never able get all the air out with the bleed block. Needed to extended the pistons almost to the point of popping out (need to be careful though because the pistons will pop out of the housing). Full bleed that way. Pushed the pistons back in, full bleed with the bleed block.

Two seasons later now and they still perform like a champ.
  • + 1
 I think Shimano OEM are poorly bleed in most cases,SRAM brakes too but shimano ones can operate whit air bubbles or less fluid,SRAM brakes not. A good bleed/clean is all you need.
  • + 0
 @Slie: I've had overwhelmingly perfect experiences with Shimano's brakes.

HOWEVER...I have had three sets total now, one Saint and and two XT, that were absolute nightmares to set up. I did eventually get all of them working fine but it took a couple of months in each case. Still can't say for sure what the problem was and if it was even the same problem in all cases. Now that's three sets out of probably 50, so i'm not complaining. It's just weird.
  • + 1
 Sounds like there is something wrong with yours. I have Zee on my DH bike and they have never failed me nor even been inconsistent.
  • + 2
 Same problem with all shimano brakes I've owned Zee and SLX. Pads seem to glaze over after every ride. Takes a run to get them working again.real pain when your diving straight into a dh track on an uplift day. Lever feels sharp and not spongy so Thinking of trying a different brand of pad.
  • + 1
 @bigtim: the problem isn't with the bleed as they do that after being properly bled. On top of that, I had to replace one lever because it was leaking.
  • + 3
 Very interesting! Tech tips are too often so obvious that only newcomers cab learn from them. I'd like to see more of those tech hack, like tricks & pro-hacks on tires, brakes and suspension!
The science of tire cut would really be the most interesting!
  • + 3
 Nice video. Jude knows what he's doing that's for sure. I'd never heard of either of these techniques, but am glad to now have them in my arsenal. I've ridden pretty much every brand of brake and have gotten to like the newer Magura stuff a lot. MT7 front paired with MT8 rear. Have taken the time to learn how to get them and keep them pretty dialed all the time and am really happy with them. After years of trying to go weight weenie on rotors, I've learned that more substantial rotors help a lot with keeping things quiet and reliable. if you haven't run Maguras or think you hate them for some reason, I encourage you to give them a try. They're really pretty simple to work on. All the hardware is T25 and the oil is non DOT.
  • + 1
 Thanks rbuck9!
  • + 5
 just dont buy avid brakes and you should be fine.. really, its pretty simple. have never once had an issue with any of my brakes that were not avid.
  • + 3
 Jude knows his stuff. He correctly routed my front brake cable years back at the fruita fat tire fest after I had incorrectly routed the cable on the outside of the fork. He didn't make me feel like a jackass even though I was. Good dude and thanks for the tips.
  • + 1
 Thanks Doublejj! Fruita is one of my very favorites!
  • + 2
 Bring the hate: I have had sets of all the brakes being discussed here. Honestly, I like my guides the best. Way better modulation than shimano, never a wandering engagement point. Strong (but not as strong as shimano but more usable) so easy to bleed, if you are having trouble you are doing it wrong. Always exactly what I expect when I grab a mitfull of lever. But I must admit I have switched the centreline out for ice tech on the rear brake it was doing the avid turkey scream. Doesn't do it with the ice tech. If you can't bleed a guide you need to invest in a quality bleed syringe kit. Vacuume bleeding guides is as easy as it gets. Like shimano but wandering engagement and light switch bite is not for me. I'm noticeably faster on the guides.
  • + 2
 Jude is clever. I always used to just take the wheel out, push the pads back with a (clean) flat bladed screwdriver, put the wheel back in and pump the lever a few times. This resets the pistons in their bore. But his approach is more convenient if you're out on the trail. I usually wear gloves anyway so I'm not concerned about grease transferring from my hands to the rotor.

I never reset a PM caliper with worn pads. I know PM is great for the OEM market but I always preferred IS. If you set an IS caliper up properly, it stays properly. No surprise it were the higher end after market brakes that were the last to make the switch. That said, if I need to reset a PM caliper I put a fresh pair of pads in, reset the caliper and then put the old pads back in.

I'm not convinced about the necessity of cleaning your bike. It takes time that's better spent riding Wink . Sure the drivetrain needs love and the stanchions deserve a wipe, but really, what harm is the dirt on your frame going to do? On the other hand, I do believe cleaning could potentially cause damage to your bike. And indeed, splatter grease on your brake surfaces (rotor or rim).
  • + 1
 Thanks for your comments and you are correct that IS was a much more accurate mounting solution!! Good call.
  • + 2
 I have a question. Is it possible to contaminate your rear rotor by washing your bike? Sounds dumb but wait. You've lubed your chain properly, (wiped it off after lube soaks in)then go on a rather muddy ride. Since riding it hard and putting away wet is never a good thing,(I'll leave the lascivious jokes out) you hose off your bike. As your spraying your cassette chain area off some droplets that contain oil splash onto your back rotor possibly contaminating it? Does this sound plausible?
  • + 1
 I generally use washing up liquid and warm water to wash my bike, i'd heard it contains a lot of salt to help with the cleaning so generally if i'm really thorough rinsing its ok. If I forget to rinse my rotors they need a heat cycle through them to burn off the residue before they start working properly again, so I'd say yes its possible.
  • + 1
 @fattyheadshok One of the most significant improvements I found when washing my bike was to NOT clean the caliper and disc at all-just a hose rise with NO detergent on the disc or caliper during cleaning, finishing with some blue towel paper to dry things off. Going in with a brush or sponge used for other parts of the bike will contaminate the braking surfaces.To what degree is debatable depending on how aggressive you are with cleaning and detergent. Its worth pointing out that braking friction relies on a layer of pad material remaining on the disc- this is what you create when you bed-in new pads or new brakes. Cleaning that off religiously every time imho is counter productive and degrades performance. If your brake caliper area is still significantly dirty after hosing, remember most of that mud can come off when dry but keeping suds AWAY from the brakes certainly for me appears to have almost eliminated brake noise in all but the most prolonged wettest conditions. I stopped having to deal with contamination and sanding of pads when I paid less attention to fastidious cleaning of calipers/rotors-and when i stopped using branded brake cleaners like Muc-Off- which i have only used when pads are removed from the brake caliper. Their claims about 'refreshing' pads are bunk. Also, if you're using silicone spray or any aerosol lubes with your wheels in the bike (I remove mine for cleaning) use a cheap carrier bag wrapped around the caliper and disc- a virtually free method to eliminate over spray. FWIW I use Hope brakes.
  • + 2
 Absolutely. Especially if your using a brush to clean the drivetrain, the flicking action flick oil to the disc. I have done it on many occasions despite my best effort not too. Also I find brake cleaner makes the brakes less powerful and much more noisy for some reason.
  • + 1
 I dont apply chain lube after washing my bikes, i do it before i ride. I apply it next to the chain ring whilst turning the cranks slowly! But it probably still gets on the disc! Its just one of those things!
  • + 5
 @Braddlie: Disc's on the oppo side you daft pudding.
  • + 1
 @Braddlie: sorry man but...you're doing it wrong if you're getting oil on your discs. It's never ''just one of those things" and if you do wash your bike, its generally accepted every time to replenish the lubricant you've just stripped out of your drivetrain. As I suggested, regardless of when you apply it, cover the discs with a plastic bag, or use a more viscose lubricant.
  • + 1
 You've got that right! Be aware of soaps and solvents landing on the rotor and causing friction issues and noises.
  • + 5
 "Definitely bust out the gloves and gobbles" - which part of you body do gobbles go on?
  • + 4
 Special glasses for hunting Turkeys.
  • + 2
 2 Reasons Why Your Disc Brakes Don't Work... Avid & SRAM.

DH bike has been sitting unused in a heated garage... yet the rear brake is pumped & dragging. A month ago it was fine, so frustrating.

Yet by Shimano's haven't been serviced for 2 years and work as good as new.

The only thing I'll buy from SRAM is a chain, thanks for the quick link guys!!
  • + 1
 just buy a Shimano chain and put a kmc quick link on it.
  • + 2
 It's common knowledge that if your brake pads are contaminated with oil you can't just sand them down, the oil has already soaked right through the friction material by this point and there is no bringing them back! Surely Jude knows this... It's basic science.
  • + 1
 Exactly craigtrails! This tip is not intended to resurrect a soaked set of pads, only for glazing or polished pad faces! Good point and thanks for the call out.
  • + 1
 @rjude: Thank you for clarifying that Jude! I'm not a fan of people being misguided by badly written articles.
  • + 2
 I don't think this technique will work with a through axle but here is what I did to reset the pads in my good (bad) old days when I ran Hayes brakes on QR wheels. Just release the quick release so the wheel is loose in the dropouts and wiggle waggle the whole wheel. Pushed the sticky, and the pistons were always sticky, pistons back in place and no touch to the rotor itself.
  • + 1
 Technique works with any axle configuration!
  • + 2
 FYI for cleaning rotors, if isopropyl alcohol is not enough then take them to your sink and use a cleaner with bleach in it. You want to scrub with the bleach cleaner until water forms an unbroken sheet on the rotor. If it beads up anywhere, there is still some oil based contamination in that location.
  • + 2
 All you wanted to know about cleaning surfaces:

youtu.be/HiL6uPNlqRw
  • + 2
 Timestamp of the specific comparison between Isopropyl and bleach cleaner: youtu.be/HiL6uPNlqRw?t=11m8s
  • + 1
 I'm still running a set of late 2000 Hope Minis, strip them right down every other year, clean the pistons, new seals and re-bleed. If you look after them, they will last. I can still stop on a dime. Rubbing alcohol in a spray bottle will help clean the crap off after a drive with the bike on the rack, and it's cheaper than brake cleaner.
  • + 1
 @rjude: Now that you're here, I've got one more question. Sometimes when I've got air in the system but don't have time to bleed, I tilt the master just above horizontal, gently squeeze the lever and let it snap back a few times. This usually chases the air into the reservoir and I'm good to go. Then back home when I do have time, I do this again, push the pads back, open the reservoir (I'm running Louise brakes), top it off with oil and close it again. Never got me issues and I rarely go through a full bleed.

Then some other Pinkbike visitor advised me that this is not ideal as over time, water accumulates in the caliper so that if the brake gets real hot I could get a vapor lock and loose all my brake force. Now, I usually brake short and hard so rarely get the brake that hot but of course it seems to make sense what he said. The Magura manuals don't recommend a regular bleed. Do you agree with the manual or do you agree with the PB visitor that I should go through a full bleed every now and then?
  • + 1
 Hey vinay! There is zero water accumulation with a mineral based hydraulic brake system because that is the advantage of mineral fluid, not hygroscopic which means it does not absorb moisture like DOT. I think your technique is fine and it is not necessary to ever perform a full bleed if not needed. Mineral fluids last for a long time, like up to 10 years for the above described reason, non-hygroscopic! It may look discolored but that is not affecting the performance noticeably. Thanks for your comments and support!
  • + 1
 Top tip: If you brakes aren't working so great, ride around with the brakes on or down a steep hill, and then immediately douse the brake caliper and disc with water. If it was hot enough it will fizzle. Ride again and brake hard once or two. Voila, full power! If it still didn't work repeat again and you should be fixed. Magic, don't know why it works but it does. Use it at work when some brakes just refuse to come good even after sand paper.
  • + 1
 here's a cheap fix for contaminated brake pads........first it only works on pads with a metal backer. Burn them with a small torch or heat them up on your stove element baker plate down until they turn red hot.....by the time they are red hot.....contamination will be completely burnt off. then thoroughly clean your rotor with rubbing alcohol.
  • + 1
 Just wait until the pads are cool before cleaning with alcohol;-)
  • + 1
 Automotive brake cleaners I've come across are mostly isopropyl alcohol sprays, or rarely petrol based.
99% of the time they are hardly capable to do any damage to painted surfaces or rubber seals. Just be sure to read what the label says first and stick to trusted products. Then you can spray it all over the place, it'll evaporate quickly.
  • + 1
 Nice article. One thing that I tried out of desperation after contaminating my pads could be of help to someone. I'd contaminated my new pads with oil on the bench. The pads will absorb the oil and sanding will not remove it. Having no other pads I attempted to use heat to burn off the oil. I applied heat with a propane torch until they stopped smoking. Oil is gone and the pads bedded in and worked just fine. Probably a dangerous thing to do so use with caution as you will likely overcook the adhesive bonding the pad to the backing plate.
  • + 4
 I bake them in the BBQ for 5-10 minutes.
  • + 1
 You are correct in that the pad material can separate from the back plate plus this technique typically hardens the pad material so you get less friction and possible new noises. But, in an emergency, you must get creative. Good try!
  • + 3
 Awesome video tutorial. Though some bike shops run clinics, they are often the very basics and don't cover small tech maintenance like this. So thank you for posting.
  • + 1
 Just last night I managed to shatter a ceramic SLX piston as I was pushing it back in for a pad replacement. I was using a 10 mm allen key which I have done many many times before. Weirdness indeed but the good news is that a new SLX caliper is only $21, XT $35 on Jenson. Live and learn and at least Shimano brakes are dead easy to bleed.
  • + 6
 i've found that a plastic tire lever works perfectly on ceramic pistons.
  • + 4
 OK, it reminds me that it´s time to change brake fluid in my Hayes MAG to work flawlessly 20th season...
  • + 2
 These instructions weren't clear. My girlfriend is in hospital with a pitchfork stuck in her face and I'm typing this while hanging from the rafters in the garage and facing jail time. Please be clearer next time.
  • + 1
 I'll try!
  • + 3
 This is why i bring my sink and dish soap on rides. Then I can wash my hands before I do the rotor bendy maneuver.
  • + 1
 just switched sticking guide rs with xt and left guide rs on the other side to compare. xt has great feel, guide is slow to bite and not very precise. Why do so many magazine articles praise the feeling of sram mush?
  • + 0
 It's called modulation. Learn to ride not stop and slide. Also enjoy the lever Jack on long decents...
  • + 0
 @Jokesterwild:

People who know how to ride don't need no one modulating for them. But you would know, I guess...
  • + 2
 @mollow: yeah? Tell every race car driver that. "now when you hit the brake pedal it just locks up. It should be fine though you know how to drive"
  • + 1
 Yeah sorry I forgot we were talking about cars...
  • + 3
 I feel that if my brakes won't lock if i pull them to an exact point, I'm not getting enough power from them. I modulate with my finger.
  • + 2
 Grinding the pads / rotor cleaning works and always has done... great information for a whole bunch of folks who didn't know about it.
  • + 5
 Avid BB7s for life
  • + 1
 Never have to bleed avid mechanicals
  • + 4
 Just twat it with a hammer
  • + 3
 Surely a far more common complaint is "my brakes are squealing like a stuck pig" ... ?
  • + 3
 I think Avid/ Sram brakes are supposed to sound that way?
  • + 1
 I believe that's usually from not properly bedding in the pads/rotors. It can also be the materials used.
  • + 2
 Wow. Of course you can touch the rotor. The oil on your skin will burn off with how hot your brakes get. Biggest load of shit I've ever heard, and from Vernon.
  • + 1
 You are correct in that you can touch the rotor. Vernon is a very smart person and he just implied to be careful with what is on your hands prior to fondling the rotor.
  • + 3
 Didn't know about that first tip. Can't wait to try it out
  • + 3
 Is it a 26 inch bike? In that case it is not useable facts! Just saying
  • + 2
 Rotor bending trick is damn good, been hitting my head against a wall with this brake for weeks. Bike so fast now Smile
  • + 1
 Years ago, Gary Fisher Sugar years ago, a mechanic at Over The Edge in Fruita showed me the first technique. I was ready to buy new brakes I was so frustrated.
  • - 1
 lol don't touch your rotor with your bare hand?!? We ride through woods all day, clean the bike and get god knows what spray onto it, these things receive some abuse but you have to worry about not touching it with your grubby little hands, yea ok
  • + 10
 If you have oily / greasy hands from doing other spannering you're gonna have a bad day!
  • + 0
 Your skin has a natural protection - a kind of grease. If you touch your rotor with your fingers, you applie this grease on it. I NEVER touch my rotors with unprotected fingers.
...by the way, i have Guide RS brakes. Don't know much about trouble. On a 1000m descent in 15min. they are on the edge, but (unfortunately) this is rare.
  • + 2
 Freeway driving in the wet with bikes on the back rack of your car, will cover your Rotors in road oil Crap!!!
  • + 1
 I hope young people will see this braking news as it spares me from stopping them going into my shop to remove that glazed look from their eyes.
  • + 2
 When's the 'How to bed brakes' article coming? That was good.
  • + 0
 Do you have to do foreplay with them before you bed them? Or can you just go straight to it?

Inquiring minds.
  • + 1
 @HpSauce: I usually stroke them and squeeze them over and over until they pull me up hard enough to be sure I can use them for wild adventures in extreme scenarios.
  • + 2
 thanks i will give this a try next time my brake is dragging.
  • - 2
 Am I the only one who swapped my Saints for Guides? The Saints looked sick but it was a 50/50 chance they would actually stop me. Look at Brook's crash in Leogang, they claimed it was brake failure and to my surprise... he was riding Saints.
  • - 2
 "Am I the only one who swapped my Saints for Guides?"

You might be. First i've ever heard of a successful swap in that direction. HUGE downgrade in my experience...but I guess anything's possible.
  • - 1
 Either listen to thousands of different people calling out on their issues and problems with Sram/Avid brakes or listen to ONE major failure of one Shimano brakeset.
  • + 5
 @carfreak2000: As a mechanic I've never had any problems with either. I just prefer the lever feel and power of Guides over anything from Shimano.
  • + 1
 It was apparently the brake mount adapter that failed and got caught in the rotor. Not the caliper its self failing. But yea you probably are, everyone I know went the other way and never looked back.
  • + 1
 @carfreak2000 Just personal experience, mine were shite, my mates XT's were even worse. I wasn't asking how much more superior you believe shimano to be, I asked if anyone else has had such an experience. Definitely prefer the lever feel on the guides, they are nothing or full on, I must admit the Saints were easier to feather
  • + 3
 @Iain-Da-Weein: There are always going to be exceptions to the rule. Also, I don't blame anyone who has had bad personal experiences with an otherwise good brand for choosing something different. Reviews and other's experiences don't help you. You need to choose what works for you.
  • + 1
 Yes i have noticed my pistons are extended at different levels.
Still i un bolt the caliper.
Cause im lazySmile
  • - 1
 Is this really content worth publishing? Oil from
Your hands will burn off after your first few braking points....

I suppose PB has a captive audience, myself included, but Christ this just feels like a waste of words
  • + 2
 Brilliant!
  • + 1
 yours not working! Mine are fine!
  • + 1
 Low flying airplanes in his shop?
  • + 1
 number 1: they're sram
number 2: they're sram
  • + 3
 Guides are great brakes. Competition is good. Don't be a fool.
  • + 1
 Shimano SLX brakes are the best brakes ever
  • + 1
 The missed my issue, mainly being fat as fuck.
  • + 1
 brakes only slow you down
  • + 1
 They are Avids(and sram)...
  • + 1
 Just got some Hope Tech 3 V4s and can't see myself needing anything else.
  • - 1
 "I honestly can't wait to see the carnage this article is gonna cause!" - Every bike shop mechanics.
  • + 1
 Haha, yeah if this works they wont be able to sell you a new set of pads or rotor!!
  • + 1
 I would use the fish
  • + 0
 Oh bendy rotors. Yuck
  • - 3
 3. They're Avid 4. They're Formula 5. They're Hayes 6. They're not Shimano or SRAM
  • + 2
 Avid is under Sram. You do know that right?
  • + 2
 @carfreak2000: it was to differentiate the older vs. newer ones.
  • + 1
 @SwintOrSlude: SRAM Guide is same crap as the old Elixir junk. Overpriced POS.
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