Curious as to other’s experience. The piston seals in my Shimano brake calipers leak fluid, causing my brakes to squeal like Ned Beatty in “Deliverance”. Apparently, this is a fairly common problem but not so great that Shimano has any plans to recall them. Anyone else had this problem?
In my case, my calipers are two months beyond the two year warranty period so Shimano is steadfast in refusing to replace them. (Hollowtech cranks, anyone?) I’m replacing with Hopes… a bit more expensive, but according to my LBS, more reliable.
I’d be curious about other’s experiences. Although I love their products, Shimano’s customer support has left a bad taste in my mouth.
I’ve had that on a number of Shimano calipers, both MTB & road. Usually the leakage is low enough that you can burn it out after a few descents.
Extended breaks between rides seem to compound the problem.
Hasn’t worked for me. It’s been a problem for a while, and on a bike I ride 5-6 weekly in an area that is extremely hilly. After a while, it’s tiresome. My feeling is that it is Shimano’s problem. The customer shouldn’t have to adjust to “cure” a problem created my the manufacturer.
I experienced the same issue with R8070 calipers—after going through three faulty front ones, I decided to switch to Hope RS4s. I used those for two years, but constantly adjusting the pad alignment became frustrating.
Eventually, I switched to the R8170s, and I haven’t looked back. They’ve been flawless for the past nine months.
I’ve had 2 calipers do this and has driven me crazy trying to solve it. In the end, my belief is that the Shimano ceramic calipers are more prone to cracking and micro-leaking. This probably happened due to me pushing them in slightly cattywampus, but I haven’t had any other calipers have this issue. I’ve since been switching to Hayes Dominion A2s and couldn’t be happier with them. Note that they’re current 50% off on Hayes’ site.
I had Shimano R8070 calipers on a bike, got them brand new with the build. Put 7 years and 15k+ miles on them. This past year the brakes began to squeal after the bike just… sat. Around the time this started happening I lucked into hearing an episode of the Geek Warning podcast I now cannot find where Dave mentioned Shimano caliper seals did break down and develop small leaks, where leaving the bike to sit would drip a small amount of mineral oil that could contaminate the pads. Ride every day? Things are fine. Wait a week? No bueno.
So this spring I swapped them out for a fresh pair of R8170’s. Squealing has gone away, which is no surprise given I replaced rotors, pads, and caliper. So far it has not returned, and there have been stretches where this bike sits for a week unused.
Since seals have to flex, I’m not surprised by them being “wear items” that eventually need replacement. I got what I felt was a good amount of life out of them. Sadly, they’re not (officially?) rebuildable, so my option was simply chuck them and replace.
Again, this is on a bike that at most sits a day or two. Even so, calipers are pretty expensive to be considered a “wear” item IMO. Especially when the “wear” seems to be about 2 years in my case, and they are basically trash.
On an n=1 sample with no background as to riding, frequency, cleaning and maintenance regime (especially piston resetting), tools used etc, this sort of comment is the basis/fuel for urban myth and confirmation bias. Noting I’m NOT saying the OP didn’t live this experience. Just that context is EVERYTHING.
The most popular disc brake in the world, with literally tens of millions of users, will always fill forums with examples like this. I have replaced loads of leaking Shimano calipers over the years - every busy mechanic has. But we collectively haven’t replaced millions that are still working just fine.
Hopes fail too. They sell rebuild kits for exactly that reason. But Hope have maybe 1/1000th of the market Shimano do, so chances of hearing of a Hope failure are how much? and yes they are a royal PITA to work on. I’m about done with the RX4’s on my gravel bike - they work fine, but GRX will do the job just as well with 1/10th the faff.
My counter to any n=1 Shimano-are-shite anecdata is that the Shimano calipers on my GT i-drive 3.0 were still going strong 15 years later when I sold the bike.
What does my n=1 add to humanity? Dunno.
…and can we just pause for a sec to marvel at the modern bike disc caliper? Look at the forces and temperatures a few fingernail-size pistons and fancy rubber bands are asked to tolerate, hundreds of times per ride, all the while being coated in road and trail muck, cleaning fluids and often-questionable maintenance regimes. Oh, and with an RRP of an average-table-size round of drinks. Chapeau my wee grippy friends.
In our shop we rarely run across leaking pistons that aren’t cracked…usually by customers who try to bleed their own brakes and attempt to push the pistons in incorrectly. The ceramic pistons generally won’t crack or leak if handled correctly. There are always exceptions, but we have plenty 10-20 year mtbs with thousands of Colorado mtb single track miles coming through with the original pistons still working just fine.
I’ve had this same issue on the rear caliper ever since I bough my bike with a new DA 9200 system. It seems there is always black fluid that surrounds my rear caliper that I have to clean off.
I replaced leaky ultegra calipers with Hope RX4s a few years ago. No leaky pistons for me but worth noting they have their own maintenance foibles. For starters the bleed process is much more involved than a standard shimano bleed - it’s not hard per se but you need to get all the steps right for the bleed to work. Mine also need a bit more TLC keeping the pistons lubed.
Woah there John - a bunch of people have posted their experience. You said you were [quote=“John_Tonetti, post:1, topic:1188”]
Curious as to other’s experience
[/quote]
So actually, was what you were after was validation that Shimano make poor products, and you’ve been hard done by? What sort of response did you expect? No-one abused or berated you. I personally found the replies useful.
I’ve worked on and bleed 100s of shimano calipers over many years and personally see a very low failure rate, especially with the newer calipers, i.e. ones with the black pistons.
As other have said above, failed calipers is normally due to a cracked piston where the owner has forcibly retracted the piston when changing brake pads.
Not saying there aren’t some calipers than are faulty, I just dont see that many of them in my sample size.
I have 105 callipers on both summer and winter bikes. Summer bike with 25kKm has been pretty faultless, only squealing after wet or lazy bleeding. Winter bike has been generally okay but more prone to squeal, including during occasional dry summer outings. One the whole I’d say they’re pretty good and trouble free. Have recently change from stock pads to uberbike and no great difference except price and greater pad thickness.
My rear 8070 calipers are bad for leaking and squealing. I don’t do myself any favours by hanging the bike vertically and then often not riding it for 2-3 weeks. Power improves slightly if I drag the brakes for a bit to burn off some oil but I think I will just replace the rear caliper.
I am tempted to try rebuild it because I’m cheap but I don’t have time to ride it regularly let alone find time to rebuild the caliper with parts of questionable quality in order to save about $40AUD. (seal + piston is ~$20, pads $25 and a new caliper with pads is $80)
I have 4 sets, all mtb. 50% of them leak. Funnily the older sets are the best. It just annoys me that you are expected to toss them. I listened to the Geek Warning podcast and it sounded very familiar. I was just glad to hear that it wasn’t only me having issues.
Dear Mike, you made a lot of assumptions here as opposed to actually asking me about the things you picked on in my original post. As well, your “point” that there are millions of calipers that haven’t been replaced is somewhat specious, and pretty much the same point Shimano made about Hollow Tech, until they couldn’t.
So, to answer your questions, this bike gets ridden quite frequently. I have 12,000 miles on this bike which I purchased two years and two months ago. It has gotten full service (including brakes pads, calipers, and bleeding) at least three times and I have replaced the pads 3x and the rotors 2x before this most recent occurrence. None of this service was self-performed, but all done in my LBS by professional, Shimano-certified wrenches.
But my underlying point, which I thought I’d made clear, was that according to Shimano, my brakes were 2 months out of warranty and so “Tough nookie” to me. “Buy new ones”. That Hope (and other manufacturers) do make rebuild kits and Shimano doesn’t speak volumes to me about Shimano’s respect for its customers and its products.
And as far as this being “N+1”, that is another critical assumption on your part. In fact, I spoke with both of the two large LBS’s that had serviced my bike in the past, and both stated that they saw this on a fairly common basis. In fact, one said it was so common that he figured it was 50/50 that if I purchased new Shimano calipers that I would have to replace those in two years, too. I asked the question to validate whether their experience was accurate. And FWIW, I’ve never had to retract the pistons when working or cleaning my bike because I use spacers in the calipers after removing the wheels.
But thank you for your response. My fault for not including a full case history before asking a question.
Certainly more info is useful, but it doesn’t change the reality. Yes, some Shimano calipers fail within what would be considered a premature distance / age. So do others.
Your shop said they see Shimano failures often. Above in a post Alex said he doesn’t. Neither do I. Is this confirmation bias either way? Maybe.
The Hollowtech comparison isn’t really valid - that was Shimano ignoring a clear safety failure, and not instigating a return program quickly and effectively. The caliper issue here is almost certainly tied to maintenance, how it’s done, how and where the bike is ridden etc. many variables.
I have probably a hundred repeat customers on Shimano calipers for the last five years, none have failed. Is that a representative sample? Dunno.
I have had customers bring me leaking callipers, from every brand. But I have zero idea as to history, so can’t claim proof or not of a systemic issue.