Are you riding in ridiculously cold temps? Could be that the mineral oil, or seals or some such brake related component is acting funny in the arctic air. Thing is, adverse conditions generally make brakes work worse.
The next Shimano gravity group? opinions?
- Thread starter hitar_potar
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On the DH bike when I was having all sorts of problems with them, no, summer temps.
Been riding the fat bike in the cold and snow since Turkey day, anything from 50's to about zero. No noticeable problems, but, like I said, I doubt I'm going fast enough often enough or hitting big enough stuff to have additional problems, since fatbiking in the snow is pretty damn slow. It seems to be a bubble bouncing around problem that many others have had with the shimano's.
It's definitely a design flaw in the Shimano levers, I firmly believe these problems aren't to do with end-user choices (like bleeding) or external factors like temperature, plenty of other brakes work fine under questionable conditions and even questionable bleeds.
I think poor routing exacerbates the pre-existing problems (just like I mentioned that the piston/bore wear exacerbates the problems over time too), but as you've hinted, other brakes including Shimano's own from early generations have endured these things without problems. These aren't new problems either, they've been ongoing since the M785 was released, and are present in every brake since (including the latest M8000 - finally even Pinkbike got a problem set in their review) So basicallly, this is 100% a fault that needs to be addressed by Shimano's brake engineers, not the end user.
You're having a point! Just checked on new Formula levers, ~160 Eur each, the whole T1 Racing set comes at 330. No definitely no The Franken Ones for me.
Power wise the XT was a new level compared to my old T1, but on the other hand I think the T1s were in a need for a bleed when I swapped them out. Anyways, I will try a bleed an see what happens.
I've used my m987 (almost exactly same as m9000) brakes down to about -20F, no issues, kind of stiff and on/off at those temps, but last year I had an avid with DOT on the other side and it was pretty much the same at those temps. Upgraded to m987 f and r on the fatbike due to this, been warm this year, only once down to about -10 to -15, but no big issues.
I am pretty sure there was an air bubble in the most rearward portion of the caliper while bleeding the rear, I had to turn the frame to get it to go up to the lever, was a little funky.
Brakes were flawless riding DH in sub zero today. Even wore my rear pads down to the backing plate (I'm Scottish so gotta get my money's worth). put a new set in and brake felt good as new. Few crashes. bike upside down a couple of times and no rear lever inconsistency or anything to report really. more of the same tomorrow so let's hope they're sorted..
One extra little thing I did do was when doing the strapping the lever to the bar trick I hung the bike upright overnight with the front wheel at the highest point allowing any air to travel from the caliper up to the lever with no chance of air getting stuck in the kink in the hose from the caliper to the chainstay routing.
One extra little thing I did do was when doing the strapping the lever to the bar trick I hung the bike upright overnight with the front wheel at the highest point allowing any air to travel from the caliper up to the lever with no chance of air getting stuck in the kink in the hose from the caliper to the chainstay routing.
So, what some of you say, is this problem with Shimano brakes is present even on the XT 8000, is that it? This would mean it's present on the XTR 9000 too?!?! In the same time, i've got friends riding Zees and Saints for years now without whatsoever issues...
i'm still running first gen saint calipers (m800 i believe) with same gen xt levers. shits still flawless.
The first half of 2017 is almost gone - still nothing from Shimano regarding the gravity groups.
Magura's going steady with the MT7 and updates for it (the new aftermarket lever), Sram introduced the new Code, Hope V4 has its own fan's croud, we keep hearing more and more about the Trickstuff Dirretisima brakes, TRP signed Aaron Gwin and went berserk... Shimano, what gives???
Magura's going steady with the MT7 and updates for it (the new aftermarket lever), Sram introduced the new Code, Hope V4 has its own fan's croud, we keep hearing more and more about the Trickstuff Dirretisima brakes, TRP signed Aaron Gwin and went berserk... Shimano, what gives???
saint works and shimano's focusing on trickling down their electronic crap?
I've wondered the same thing.
FYI the new XT brakes are even more problematic than the previous generation, so somehow I doubt a new Saint product will actually be better unless it sees a thoughtful and complete redesign. However given this timescale maybe they are actually doing that.
Almost everyone I knew on M820s has now switched to other brakes for consistency/reliability reasons. Most of them switched to Hope V4s, which definitely aren't as powerful IMO, but are a way higher quality brake and are much more reliable. Shimano brakes are completely disposable these days, 1 hard season and bin.
I've ridden the Diretissima and was very impressed by the power, but when Pinkbike reviewed them they had some problems - and at their ridiculous price, the acceptable number of problems (and excuses) is zero. The reviewer was Paul Aston too, I find his words are closer to reality than the others.
The Maguras are powerful but they have the most horrid levers, just plasticky/cheap + fall apart real fast, topped off with awful geometry. Spent last summer riding with a guy sponsored by them and they were always in shambles and held together by various ziptie contraptions. The 4-pad thing is unnecessary and weird too. He was a big guy and liked the power though.
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the levers on the mt5s I have are garbage. very disappointed. been thinking about swapping levers with the XTs on my trail bike to get a more comfortable lever and more power on the DH bike, then lighter weight and smoother engagement on the trail bike....but I don't have time for that nonsense.
Finally gave up on my old saints M810s after about 5+ years of use, winter, summer, etc. Started to get air inside often, which means it needs a new seal set and it'll be back up and running. These saw use everywhere here, DH trail you name it.
Got a 2 season old M785 off a buddy, no issues either, holds a bleed and has been used for DH in Canada as well. No idea why you guys are having issues, we have colder winters here and we still ride in it all, and our downhills are on par with anything the world has to offer, so I'm really curious why people are seeing them fail.
Also have XTR M970 or whatever those ones were, no issues at all. Still running them with a 2 year old bleed.
Have used all former XT brakes, Deore, Formula R1's, Various hopes through the 2000s (team deal, had em all, single to 6 piston). Can't say anything bad about Shimano other than it requires a bleed more often in DH applications due to the nature of mineral oil.
If the saints are still here this year, that means there will be something new next year, I'd watch this space.
Got a 2 season old M785 off a buddy, no issues either, holds a bleed and has been used for DH in Canada as well. No idea why you guys are having issues, we have colder winters here and we still ride in it all, and our downhills are on par with anything the world has to offer, so I'm really curious why people are seeing them fail.
Also have XTR M970 or whatever those ones were, no issues at all. Still running them with a 2 year old bleed.
Have used all former XT brakes, Deore, Formula R1's, Various hopes through the 2000s (team deal, had em all, single to 6 piston). Can't say anything bad about Shimano other than it requires a bleed more often in DH applications due to the nature of mineral oil.
If the saints are still here this year, that means there will be something new next year, I'd watch this space.
How good were those things. I ran mine for nearly 5 years and only retired them due to the lack of parts when the master cylinders failed. A combination of stubby fingers, an old hand injury and having generally retarded personal preferences means I'm super picky about brakes and at first I thought I'd hate the M810s due to the lever geo. In the end, they're the longest I ever ran a brake type for and did so running their (absolutely awesome) stock sintered pads. They had their faults admittedly - varying lever throw, especially once the pads were nearly dead - but were robust as.
How they updated to the M820s and made them worse and unreliable is beyond me.
I did 5 years on the M810s as well and actually never changed the oil. They were as good on the last day as they were on the first. Only reason I got rid of them is because I traded my bike in on a new one and decided to upgrade to M820s. Complete garbage. Should have kept the M810s.
I've been on Guide Ultimates for the last 2 seasons and no complaints.
My thoughts (and hopes) exactly, but the previous time the Saint was updated, was going from 810 to 820 in 2013. And info and photos of the 820 were up on internet by the half of 2012 already. And now - nothing. I'm beginning to get scared of the possibility of Shimano deciding to update the gravity groups for 2019...
Funny, I can't stand Shimano/Guide levers. The MT5 levers feel like older Avid levers to me, which I always liked (the levers, not the rest of the brake).
I wonder if they'll make it 7 speed...
I'm still very happy with 9 speed sram shifter, shimano 11-28 cassette using a zee derailleur and adapter from someone on here...
I'm still very happy with 9 speed sram shifter, shimano 11-28 cassette using a zee derailleur and adapter from someone on here...
That would suck. I'd imagine after gwins brakeless run then switching brake mfgs, and the current market, should push them to make a killer brake. At least thats the logical business plan, but hey, who knows.My thoughts (and hopes) exactly, but the previous time the Saint was updated, was going from 810 to 820 in 2013. And info and photos of the 820 were up on internet by the half of 2012 already. And now - nothing. I'm beginning to get scared of the possibility of Shimano deciding to update the gravity groups for 2019...
They were really amazing. I put them through hell, crashed numerous times. Broken wrist, collar bone, two ribs over two seasons and brakes had a small crack on the lever and still worked fine. they are clearly tougher than me. Only other brakes that stood up like that were my older Hope mono4's, but I had to have several levers on hand to replace as they would bend if you looked at them wrong. I think I still have like 2 or 3 spare levers.
You just got lucky.
There's small variations in the seal bore tolerances so the spectrum goes from brakes that leak and mysteriously squeak on the shop floor, to developing the leak after some riding time, to cases where a leak never develops. I've attached a quote below which is identical to my experience. Current Shimano brakes are the worst by a huge margin. The old ones like the M810 were much better (although the levers do end up playing up / having throw too long eventually), I do wonder if the switch from alloy to ceramic slave pistons is part of the problem - maybe greater surface friction / seal wear. This guy (Oliver Majewski) ended up making his own thicker (2.1mm square-section) seals to fix the issue:
No time on a guide for me. I have a lot of shimano experience and a few others. The maguras just don't feel right. Maybe the throw is too long, maybe the lever is too square, but it's just not as ergonomic as the latest shimanos, in my opinion. the lever feel is direct and you don't get the sudden "modulation" that you do with shimano, but it's not my favorite. The newer shimano lever blades are almost perfect right out of the box. Plus the maguras have a plastic lever body and those shitty, coarse torx screws, so I'm always thinking I'm going to ruin something by adjusting my lever position.
Interesting. I'll post up how it fares, I'm a big guy who rides a lot, so it should be a good test under me. I'd imagine the ceramic pistons aren't finished smooth RA enough and is wearing the seals at a quicker rate, or the tolerance for the ceramic pistons are out. if you have one apart use a micrometer (not a crappy caliper everyone seems to think is ok to use, good or bust) and report sizes. I doubt I'll have mine apart any time soon, but I'm curious what's out on them.
Honestly if you bought a brake that's two seasons old and still working you've got a good one so I don't think it's really relevant for a new buyer (or a concern for you, with any luck you'll get another two!). The fact that many develop early problems is a concern Shimano should address though - it's funny because a number of my friends have had problems and each time they contact Shimano they've "never heard of it before".
I do believe in problems being acceptable if you can fix them yourself, so if I had one with bore issues I'd contact Oliver for some seals, and if the ceramic surface was a concern I'd consider fitting some of the previous-gen alloy pistons (M800 for 2-pot, M810 for 4-pot), but the other issue some of these brakes develop is a varying lever throw mid-run. I have no idea what causes that or how to fix it, and it's scary when it happens. My M810s never did it (4 years) but I had M775s with the same lever that did do it, and seen various M785 and M820 that have done it.
I still rate the power on Shimano brakes as #1 (well, until I tried the Trickstuff Diretissima) so I hope they fix them, but I cbf playing the "good set roulette" again.
My first set of 785s didn't do it, even in a season of poor maintenance and hard riding.
My 810s did it occasionally, not scary style but definitely "that's odd". A bleed helped immensely.
My new 785s seem to do it occasionally, but I haven't ridden them enough to quantitate. They're on the trail bike, so relatively low risk.
My 810s did it occasionally, not scary style but definitely "that's odd". A bleed helped immensely.
My new 785s seem to do it occasionally, but I haven't ridden them enough to quantitate. They're on the trail bike, so relatively low risk.
Something funny is certainly going on with Shimano's brakes lately. My buddies both have M810s on their DH bikes, and they constantly have issues with varying bite points, and strangely, contaminated pads and rotors from letting the bikes sit. After 2 weeks in the garage, both guys will have signs of pad contamination (loss of power, howling pads/rotors). This same phenomenon happens with one of those guys' XT brakes on his trail bike, and happened with 2 sets of my dad's XT brakes.
Yeah, the plastic is lame. The power/modulation combo is better then anything else I've tried so I'll stick with them for now. I wouldn't mind getting some time on the latest Hopes to compare.
Hmmm, i find it strange that so many people had problems with the M820s. One of my riding buddies got a pair and doesn't want to hear about other brakes. And he's around 120-130kg... No issues, no problems, no loss of power or bleeding - but his pair aren't of the first ones, he got them in late 2015/early 2016. There are other guys around us running Zees and Saints and there are zero issues as well, everybody's happy. And this ëverybody" means a lot of people. 
I keep on wondering on Shimano's silence - i am mostly interested in the brakes cause i'm more than happy with my 820 drivetrain. But am in need of brakes. This silence might force me to go Code 2018... 
I keep on wondering on Shimano's silence - i am mostly interested in the brakes cause i'm more than happy with my 820 drivetrain. But am in need of brakes.
This silence might force me to go Code 2018...
I think the variability in results is largely from the variability in riding time and style.
I only had problems with my 810s because I rode them so frequently and often.
My first set of 785s was probably luck, and an early batch.
I haven't had many problems since then, but I don't ride nearly as often as I did with my 810s.
In other words, the people with the most problems also seem to be the ones who spend literally all summer at whistler.
I only had problems with my 810s because I rode them so frequently and often.
My first set of 785s was probably luck, and an early batch.
I haven't had many problems since then, but I don't ride nearly as often as I did with my 810s.
In other words, the people with the most problems also seem to be the ones who spend literally all summer at whistler.
Is there such a brake that stays consistent and trouble-free after a whole summer in Whistler? 
Almost all of them except for shimano.Is there such a brake that stays consistent and trouble-free after a whole summer in Whistler?
Just a question. I started working in a department store shop close to a year ago but have been riding actively since 07ish. Rode a crap tone 3 seasons around 13-15, were two summers I didnt do anything but riding at a park. Got something like 93 lift days the best summer. So its fair to say I've abused brakes for a while.
So what causes these howling brakes? My set of Juicy 7s(carbons) have never made a sound. My Formula RO didnt make a sound with stock pads, with superstars metallics they scream pretty bad, even when I canged pads and rotors. Got a bit better the times I put in semi-metalic pads. So same bike, same trails, same brake different pads = different result. I have to assume pads are the problem.
The juicy brakes seldom see pad change but they see alot of mileage and subsequent contamination while being on the bike I take care of least (meaning never cleaning the rotor or pads). Still quite.
Back at the shop every now and then Shimano brakes come back after a few weeks with howling brakes. I've tried to clean the pads and rotors as well as sanding both down. Wont go away. Put on fresh sets of both, done. Next!
To my knowledge so far the squeal is supposed to come from contamination or grooves that resonate through vibration. But are all contaminations equal? If I drag a finger over my own dics I get black stains as a sign of contaminations but they are still quite but if I clean one of thoose howling bikes to were its significantly less contaminations left they still scream just as bad as before. What gives?
So what causes these howling brakes? My set of Juicy 7s(carbons) have never made a sound. My Formula RO didnt make a sound with stock pads, with superstars metallics they scream pretty bad, even when I canged pads and rotors. Got a bit better the times I put in semi-metalic pads. So same bike, same trails, same brake different pads = different result. I have to assume pads are the problem.
The juicy brakes seldom see pad change but they see alot of mileage and subsequent contamination while being on the bike I take care of least (meaning never cleaning the rotor or pads). Still quite.
Back at the shop every now and then Shimano brakes come back after a few weeks with howling brakes. I've tried to clean the pads and rotors as well as sanding both down. Wont go away. Put on fresh sets of both, done. Next!
To my knowledge so far the squeal is supposed to come from contamination or grooves that resonate through vibration. But are all contaminations equal? If I drag a finger over my own dics I get black stains as a sign of contaminations but they are still quite but if I clean one of thoose howling bikes to were its significantly less contaminations left they still scream just as bad as before. What gives?
Loads of folk complain about Superstar sintered pads being noisy. Never had that problem with them myself tho.
Superstar QC isn't great. their pads often aren't sized accurately (backing plate and actual braking material) if compared alongside OEM pads. I guess this could cause excessive vibration against the pistons when in use.
Are yours actually grabbing and stopping you ok? Contaminated pads IME won't lock up a wheel.
Superstar QC isn't great. their pads often aren't sized accurately (backing plate and actual braking material) if compared alongside OEM pads. I guess this could cause excessive vibration against the pistons when in use.
Are yours actually grabbing and stopping you ok? Contaminated pads IME won't lock up a wheel.
Cooked pads will do it too. And shimano brakes grab so freakin hard now, it does seem easier to cook them.
But you're right, usually "some shit on the pad" is what usually causes it. FWIW, even if you clean brand new pads especially with brake cleaner or alchohol, they'll squeal immediately afterwards. They need to be bedded in and on fresh pad material.
You can usually cook off anything that's not a heat glaze. I had to do this every time one of my bikes sat for longer than a week and the pistons leaked.
But you're right, usually "some shit on the pad" is what usually causes it. FWIW, even if you clean brand new pads especially with brake cleaner or alchohol, they'll squeal immediately afterwards. They need to be bedded in and on fresh pad material.
You can usually cook off anything that's not a heat glaze. I had to do this every time one of my bikes sat for longer than a week and the pistons leaked.
I have one or two rotors that just howl with every brake caliper I have. Not quite sure why, de-grooving has no effect, they just oscillate laterally like mofos and transfer the vibrations to the frame. I guess poor heat treatment?
Btw. my Saintguras are still running strong, which makes me believe that it's not the levers but the calipers that suck in all Shimano brakes. Perhaps I should find some 4 pot Magura calipers for my DH bike, too.
Btw. my Saintguras are still running strong, which makes me believe that it's not the levers but the calipers that suck in all Shimano brakes. Perhaps I should find some 4 pot Magura calipers for my DH bike, too.
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anyone running guide rsc's for heavy duty riding? thoughts? i haven't found a bad review anywhere and found a decent deal on them...
Have they fixed the issue with the faulty master cylinder that gets stuck when warm? A friend of mine is waiting for a warranty replacement, SRAM won't replace both sides until the other side fails as well.
There are problems with both. You're immune from the calipers leaking onto the pads (and eventually introducing air/voids) into the line that way. That's definitely significant.Btw. my Saintguras are still running strong, which makes me believe that it's not the levers but the calipers that suck in all Shimano brakes. Perhaps I should find some 4 pot Magura calipers for my DH bike, too.