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My spyres were pish on the cx bike, but concensus on here was that they were some early model, as only one side of the caliper moved, and on 'proper spyres' that isn't the case.
Just changed the front br505 caliper to an RX4 and it’s amazing the difference. I’ve had no issues with the back br505 but the front was always prone to fade. I tried aftermarket sintered pads and they were awful so I went back to the OE resin pads. No leakage at the caliper that I could see.
I have Rival hydroR on my CX race bike and they’ve been great all the time.
I think a lot of noise issues will be related to resonance, which will be specific to frame/fork/caliper/pad/disc combination. Changing any one of these elements may shift the resonant frequency enough to stop the squeel. Or it may not, depending upon what is resonating! ( a single element or the whole system).
regarding Performance issues I think that road discs are just not as suited to their environment as MTB discs. The road grease/grime doesn't provide a natural cleaning grit on the surfaces, and the nature of the braking (long, gentle applications) doesn't do the pads/discs much good.
I remember when discs were being introduced on MTBs and there was loads of press about changing how you brake, from long draggy applications to scrub off speed gently, to short hard applications drop lots of speed quickly, and generate lots of heat to maintain pad/disc interface. I don't think I've seen much of this with the advent of road discs, so wonder if it's been forgotten in the mists of time? Or just no longer relevant with modern pads etc.
another +1 for RX4s. Can't actually compare them to the SRAM Rival calipers I bought as I replaced them without actually using them, but the Hopes have been faultless.
Road grease and grime? What the hell is that? And if grease is going to affect disk brakes then they’re going to affect rim brakes too. Any form of lubrication is going to affect the performance of any friction braking system.
Nowt wrong with disk brakes. They work fine. If you’re having problems it’s something you’ve done either in the installation or the maintenance.
TLDR for the rest of the comments, but OP - you seem to have the classic problem of failing Shimano calipers. Squealing, lack of power, etc. Cleaning the pads and discs will fix it for a very brief period of time, but you need to replace the calipers.
If you’re having problems it’s something you’ve done either in the installation or the maintenance.
Nope, tempting accusation to make but I've done everything a home mechanic can do, and have lived with discs on MTBs for 15 or more years so am no stranger to them.
Have tried SRAM, TRP and Shimano, numerous different rotors and pad compounds (but of course, never mixing pad compounds on the same rotor). Always fastidiously bedding them in. Pads checked for glaze and given a rub with wet and dry if necessary.
If they've been contaminated it's only been with road spray which to my mind is an inherent flaw with road discs anyway 'hey, they're great in the wet, but by the way all that spray coming off the road will ruin the pads'... and I've even taken a blow torch to them occasionally to burn off any contaminants, as well as giving them a spray with isopropyl after any particularly wet ride.
Mounts all faced, callipers centred and aligned using an alignment gauge.
After all that, all my set ups have worked perfectly in the dry, quiet, smooth and powerful if occasionally requiring realignment.
But all have been gut wrenchingly noisy in the cold and wet, which is why I agree with this:
I think a lot of noise issues will be related to resonance, which will be specific to frame/fork/caliper/pad/disc combination.
Obviously my size/weight/speed/frame/fork combo just guarantees noise when stick/slip friction is occurring e.g. braking on a wet rotor.
Road grease and grime? What the hell is that? And if grease is going to affect disk brakes then they’re going to affect rim brakes too. Any form of lubrication is going to affect the performance of any friction braking system.
Disc pads can get contaminated in a way caliper blocks don't. Pads are porous, blocks are not (not since they stopped putting those leather strips in them anyway). It's mainly salt on the roads that kills pad friction ime plus oil or fuel on wet roads, or diesel soot can do it - put a bike on a car rack and it can happen. Stiuff splashed up would affect either but rim brakes seem to just get rid of it. Bigger area to brake on, faster surface speed? Not sure exactly why.
My experience is that they can be a PITA, but it's quite possible to have them be almost zero-maintenance too.
For Shimano discs, the two pieces of advice from me are fastidious bleeding and blow-torch the pads! Shimano road discs are tricky to bleed well - far more so than MTB IME - but you can get them really well bled, with good feel and boat-loads of power, just don't expect to do it first time. Unless you do it every day, expect to have a few goes at it before you get them spot on. Personally, removing the caliper from the frame so it can be moved around to release air, combined with a similar process on the lever and a lot of "flicking" and pressured release of fluid from the caliper will always (eventually) result in a well-bled system, but it may take 30 mins of dicking about before it's spot on. Make sure the caliper mounts are faced and that the caliper is *perfectly* aligned to avoid noisy brakes.
For squealing brakes in the dry, it's nearly always down to contamination - road film in the winter, and leakage from the calipers if the bike has stood for a while. Pads out, stick 'em on a slab, and heat them with a blow-torch until they look cleaner. Stick 'em back in and job's a good 'un. I did some absolutely filthy looking ones on an MTB just yesterday and after a short ride, they were good as new despite the bike not turning a wheel for 2 years. I admit that I have swapped rotors in the past, which definitely helps. I think this comes down to the resonance that others have mentioned - sometimes you just need to change something to adjust the combination of bike / rider / brakes so that they don't resonate for your particular combination.
I do think that disc brakes on road bikes can be a bit more faff than rim brakes, but not so much more and they are undoubtedly worth the extra effort! And once you've got them dialled (at least in the summer when the roads aren't as filthy), I rarely need to touch them.
I'd get your LBS to check the alignment of the mounts. We had lots of issues especially with flat mounts not being aligned properly on the fork and frame. A few mins (or hours if Ti) with the right tool and all will probably be solved
Shimano 105's here and no end of problems (extremely, and I mean extremely, noisy squealing and complete lack of power).
Have tried everything within my remit cleaning wise (pads out, cleaned with disc brake cleaner, in the oven, disks off and cleaned to within a inch of their life) which sometimes helps for a few rides but then it comes back without fail.
I have gone through a few calipers and always get the same problem. My mechanic (I am rubbish with hydraulics!) has tried for warranty via Madison but they deny any issue...so it has cost an arm and a leg.
Royally hacked off with it as the bike (which is the mile munching winter bike) does not get used when it should be. MTB disks on the other hand never had any issues (mostly Shimano)
I was thinking of going down the RX4 route as well but its quite a pricey option....if it definitely cured it though probably one worth taking...how do people find the RX4's generally, write ups seem pretty good, power wise I;m not expecting a massive improvement (at least when the Shimanos are working that is) but if they did not suffer noise i, like the OP, would be happy.
PS not that it should make the blindest bit of difference but I'm in Yorkshire.
how do people find the RX4’s
Mine have been excellent. On the other hand, the RS405s on my gravel bike have also been ok and are half the price.
Ultegra’s on my road bike here and they’ve done over 5000km problem free in all four seasons. They’ll get a bit loud in the wet but then quieten down again once the initial load of water has been scrubbed off.
Would love to get a set of RX4s but I fear this bike (a Parlee Altum) isn’t quite the one for them. Maybe if I manage to get myself a nice titanium jobby...
EDIT: Should have said perhaps, this bike mainly gets ridden from west London out to the Surrey Hills or the Chilterns or similar.
I used to have a diverge with spyres and deeply deeply regretted not going for the model up that had hydro brakes they just took so much force to slow me down (i am a fatty) my hands would be aching after any long descents.
My dad has a cx bike he's had for years that I've always maintained for him with bb7s, went through pads very quickly and always noisy.
He bought a new bike with 105 hydros last year and while waiting for me to fit new pads to it this week (first set in a year) took the old bike out then immediately decided to sell it as he's never going to ride it again after how bad the brakes are in comparison to his new bikes.
So for me and my dad's experience
Cables disks = crap
Hydro = good