Sorry, another 13thfm post about squeeling disc brakes, I admit I have a problem…

I see EBC do a tape that goes on the back of car disc brake pads. Apparently the thickness of duct tape which sounds a mite thick, am hoping I can wind the pads of my TRPs out a little to compensate.

Has anyone tried anything similar? Might put some standard insulating tape on back of pads just to see how much space actually exists.

A single bit of tape shouldn’t hurt, even with new pads.

Not sure it’ll help though.

Well, unless it melts and makes your pistons all gummy and well, crap.

Noisy brakes are typically caused by misaligned calipers.

Noisy brakes are typically caused by misaligned calipers.

Or contaminated pads/rotors

Yeah I’ve been through all that, everything faced and aligned. Mine are only noisy in the wet, think most people just live with it, something to do with pads gripping then slipping and setting up resonance with the disc and/or rattling off the pistons.

Trying anti-squeel tape is just cheaper than continuing to experiment with new pads and rotors!

think most people just live with it

I like noisy brakes. One of the few things in the world that makes me smile.

I don’t know if you do it on purpose but I really like the way you spell it ‘squeel’ and not ‘squeal’. Seems more apt for some reason.

Haha, oh god, do I post that often about my brakes? I must have a problem!

Squeel and Squeal both look equally wrong when I type them so I probably use both equally.

Try filing a chamfer on the leading edge of the pad and /or using a hacksaw to make a score in the middle of the pad.  This alters the resonance

Your explanation of why squealing occurs is correct and it’s made worse by contamination

Try filing a chamfer on the leading edge of the pad and /or using a hacksaw to make a score in the middle of the pad.  This alters the resonance

Your explanation of why squealing occurs is correct…

Interesting food for thought…

I had thought about using the Dremel to cut ‘sipes’ in the pad to help channel/break up the film of water, but figured I’d get laughed off the forum for suggesting cutting bits out of the braking surface. Any chance this would lead to it crumbling and falling off the backing plate?

I’m refusing to believe it might be contamination, it occurs pretty much from new on any pads/rotors I’ve used, and I actually don’t spend much time on roads, more often traffic free, tarmac cycle paths. Basically if that’s enough to contaminate the pads then disc brakes are definitely not cut out for road bike use! I still reckon it’s just a contamination of my girly sensitive eardrums and perhaps the flatness of my commute meaning I never generate any heat in the brakes, smaller rotors would help if I could fit them!

I’ve got Alligator pads in bb7s on my commuter. They’ve done at least 7500km as my commute is mostly on flat empty country roads. They have plenty of contaminants as I rarely wash the poor thing.

All my brakes have been silent/squeaky at some point. I think it is simply a case of trial and error finding a combo of disc & pad that work well together and getting them lined up straight.

BITD advice was to put a bit of coppaslip on the back of pads to help prevent squealing from vibrations between the pad and the piston.

Are you using sintered pads or organic?

WWhat brand of pads are you using?

If you want to stop the squealing then try shimano organic pads.

If they still squeal with those then you have a problem with your set up. (IMHO)

I very much doubt Shimano will make pads for TRP brakes though.
How are you aligning the caliper? I always do it by eye so that the caliper is centred about the rotor rather than pull the lever and expect the caliper to centre itself.
Try sandpapering the pads to remove any shiny glaze from the surface, then ride down the longest steepest hill you can find and do some heavy stops from 20mph to get the pads nice and hot.

TRP pads are basically Shimano 515/525 pads, exact same shape. Think I will try they basic Shimano organic pads, I got fixated on sintered for the wrong reasons (they were my first choice on the MTB back in the day when I actually rode a lot in muddy conditions)

I centre the calliper (when the bolts are loose) using a Hayes alignment guage (basically two feeler guages) and by winding both pads in to ensure calliper is central. Then tighten bolts, adjust cable etc. the mounts have all been faced as well so the calliper will be as square and true as it is possible to be.

I appreciate the advice about sanding/bedding in etc. but I’ve been through all that before. I’m absolutely certain this is just a stick/slip resonance thing when the rotor is wet, hence trying to find solutions to damp out the vibrations. I know coppaslip is supposed to help, just wondered if the anti-squeal tape would do the same job with less risk of contamination.

The seller has got back confirming the tape is approx 1mm thick. That sounds a lot to try and squeeze into the calliper but I’ll probably give it a shot anyway, only £6 on ebay. Will give feedback once my collarbone heals and we get some good honest wet weather to test in!

Minor update, finally ordered and fitted the anti-squeal tape.

Surprise surprise, with new, un-used Shimano Organic pads, there is no space for the tape, both pads rub on disc. Funnily enough the wheel still turns fairly well, which makes me suspect with only a little use and bedding in you could get it to work, albeit with virtually no level travel and horrendous scraping as soon as you picked up the tiniest amount of dirt on the rotor.

Removing the pad travel adjusters on the TRPs provided adequate clearance, in fact slightly too much so I had to wind the barrel adjusters out a little bit, which I’m aware will affect the feel and power of the brake. Happy medium I suspect is to keep one pad adjuster in, will probably do this when I find a spare ten minutes to waste in garage.

Current plan is to bed them in and use them a little bit, assuming everything is squeal free I’ll put up with the lack of adjustability until such time as the pads have worn a little and I can put the pad adjusters back in.

Next step is to bed them in and wait for a wet day!

😉

Hmm. They would be OK,

but just for one day.

Think I will try they basic Shimano organic pads, I got fixated on sintered for the wrong reasons (they were my first choice on the MTB back in the day when I actually rode a lot in muddy conditions)

This may be your problem as metal pads are noiser in the wet, they’re also more likely to overheat a cable brake. Might not need the tape. I use resin pads in TRP brakes, no major noise issues. Just a bit at certain speeds in the wet. I do usually file a chamfer on the leading edges but only as it seems to help reduce the pad snagging the wavy edges of the rotor sometimes if it’s not contacting totally flat (wavy rotors.. stupid idea but fashion says..)

sand your discs.

sand your discs.

Had already done so but only by hand, but to be sure have some 180 grit wet and dry sanding pads in the post for my multi-tool sander, should get the discs properly back to original surface!

In truth I might take the tape off and do this more scientifically, start with just the new organic pads with the sanded discs. THEN try filing a chamfer in pads THEN try with the tape. Then start again with new 6 bolt XT rotors…

I just fitted the tape first as I was curious to see if it would fit or not.