…and they’re not even mine!

My dad’s second hand Specialzied Crave had some horrendous howling coming from the 2 year old Shimano Deore brakes, and this is despite replacing pads, cleaning etc.

I naturally assumed this was due to the faulty seals which I thought was a recognised issue, although every bike shop I’ve mentioned this to has acted puzzled and said they had never come across it.

Anyway, he’s finally bought a new bike, some sort of Giant flat barred road variant, and it’s fitted with Shimano Hydraulics as well, some sort of non-series flat mount calliper I think. Within two months of infreqeunt riding the front one has started howling also.

He is adamant that he only uses drip on finish line oil, and that the bikes are stored in a clean, albeit probably cool, garage. He tried cleaning them and said it took about twenty attempts with a clean rag soaked in isopropyl alcohol to get all the black stuff off the rotor and calliper, and they still squeeled after that.

I’m a bit out of touch, but did the leaky seal issue ever go away, did Shimano acknowledge it, and more importantly is anyone else getting phantom squeeling with shimano callipers?

Unfortunately all the disc braked road bikes I’m eyeing up are specced with Shimano hydraulics and I’m told I’m an idiot for wanting to ‘downgrade’ to TRP Spyres…

It’s a mystery.

50 bikes in the hire fleet, all with Shimano hydros (low spec) – no problems.

I have 5 bikes with Shimano hydros currently in my garage (970, 770 and 8000) – no problems.

OTOH, we had a spate of problems with Cubes a couple of years ago.

Did we not sort of think that this might be down to a lack of use thing? SR, your bikes are out and about all the time?

I seem to recall this from earlier posts on the subject.

It’s a possibility but doesn’t explain the problem I was seeing on those Cubes.

Aye, right enough.

Good point Cody, I think there was some sort of consensus on that one, not that it makes it any more acceptable in my eyes.

My dad must be getting out for at least one 50 miler a week though so if that’s considered infrequent use then there must be an awful lot of others out there with the same issue.

So on the basis of this thread:

Cubes from a couple of years ago – problems
My dad’s 2 year old Deores – problems
New M315s – problems 😕

I’ll interrogate my dad again, see if there’s any other possible source of contamination. If not I’m tempted to suggest he goes back and insists on a warranty replacement, I guess within two months it would be up to the shop to prove he’d done something wrong, rather than the other way round.

This is what puts me off discs on a road bike, that and the constant adjustment the new brakes on my MTB seem to require to keep them from rubbing, grumble grumble etc etc…

IMHO one of the problems with disk brakes on (certain) road bikes is that they’re rarely/never getting hot enough. The pads/rotors need bedding in and they’ll also get contamination off urban roads. My BB7s used to suffer from this when commuting in Edinburgh. I’d take them down a decent hill once every couple of weeks and make sure that there was a bit of heat being generated.

My first theory was exhaust fumes contaminating.
Then iffy disc cleaner – but alchohol was no better.
Now it’s just a thought of iffy batch/seals shrinking etc.
I don’t think its lack of heat – I’m a big lad (14st) and could cause my old Juicy’s to fade and overheat ocasio ally – Shimano’s solved the fade and sticky pistons of the Juicy’s though. However the first Shimano’s died after I started commenting on busier roads, so maybe it is oil deposits…

Could it be the pad material?
The cubes were noisy but others in the hire fleet are not. Perhaps the Cube was specced with a different pad?
I have a set of basic deores on my hardtail run them on cheap sintered pads they seem to be very good.
On a few occasions when I have had to clean really oily contaminated discs (on a \S?H bike i bought) I have put them in the dishwasher 😀 Came out like new.

Cleaning rotors…But not pads?

Quite a few of the older square ‘deore’ type pad calipers leak.

Calipers that use the newer pad design are less prone to leaking but have lever issues. Take your pick :p

Then iffy disc cleaner – but alchohol was no better.

Chemical cleaners are crap, just about ok for greasy fingerprints, use wet and dry and soapy water.

He tried cleaning them and said it took about twenty attempts with a clean rag soaked in isopropyl alcohol to get all the black stuff off the rotor and calliper, and they still squeeled after that.

That’s because “Chemical cleaners are crap”, It would have took 10 minutes with a piece of wet and dry and a bowl of soapy water and he’d have had better results.

its oil/gt85 etc see it every week, always accompanied by the same story of “i’ve never sprayed anything on them” until a quick wipe of a finger shows them to be caked in oil of some sort. cleaning won’t fix it because the pads are porous and the oil soaks into them.
clean the disc change the pads and don’t spray gt85 etc anywhere near them.

or possibly glazed pads but this is far less likley.

always accompanied by the same story of “i’ve never sprayed anything on them”

I do not own *any* aerosol sprays for the bikes. I have a drip on chain lube.
I’m struggling other than some WD40 buried in the back of the shed and deodorant to think of *any* aerosols in the house.
So no, I didn’t spray them.
Bikes are washed in plain water or occasionally proper bike cleaner (Sh*t shifter or MucOff).