GRX sintered pads a...
 

[Closed] GRX sintered pads are a bit ... rubbish

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So recently upgraded to GRX calipers on my gravel bike which come with Shimano sintered pads. To say I'm underwhelmed with them is an understatement. I'm using 160mm rotors and they just seem to lack any power. They're also really noisy!

Is this normal for sintered pads? I've always used resin on my other bikes and been really happy with them - however I thought sintered were better for longevity.

I went through all the usual process of bedding the pads in as I do on my other bikes. But I can't help feeling that they're not meant to be this poo. Could I have a duff set?


 
Posted : 23/04/2021 7:24 pm
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I'd be tempted to say all sintered pads are rubbish for gravel riding. I hardly brake at all on a lot of gravel rides so there's never much heat in the brakes so if they're sintered they will squeal. Id switch to resin.


 
Posted : 23/04/2021 8:10 pm
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I’d be tempted to say all sintered pads are rubbish for gravel riding

I’d echo this, if you were riding in really poor conditions they might help, but generally just don’t seem to get worked hard enough. I’ve got sintereds in at the moment too, same issues unless I’m really hauling on them


 
Posted : 23/04/2021 9:10 pm
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I have Ultegra discs.

Original pads were resin but I replaced them (at around 4,000km when they were worn down) with Shimano sintered pads (which may or may not be the same as GRX) in the hope they'd last longer (and deal with heat better) rather than expecting better "performance".

I can't say they brake any more efficiently but I'm nearly 200lb and have some massive 900m+ descents nearby so time will tell whether the last longer...
The front does squeal like a banshee though, so if they don't fix themselves, I may need to switch back to resin for the sake of my ears


 
Posted : 23/04/2021 9:13 pm
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The sintered pads in my Shimano 105 level brakes were definitely better than the organic Shimano pads I accidentally replaced them with. Back to sintered next time (road bike).

Did you bed them in properly?


 
Posted : 23/04/2021 9:20 pm
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Have you checked that the pads are pressing the discs evenly? Sometimes the pistons can settle to a position different to the initial caliper centring.


 
Posted : 23/04/2021 9:24 pm
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I've found the stock pads on two sets of GRX to be great stoppers wet or dry. 160mm rotors too. Did you bed them in properly?


 
Posted : 23/04/2021 9:24 pm
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Mine (boxed aftermarket) came with resin pads which have been great, but got some spare sintered to compare. The MTB finned sintered pads are great, so I’d expect the same from the road/gravel pads.


 
Posted : 23/04/2021 10:09 pm
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I’m bedded them in the same way I do all my other pads. Did the marshy rubbing together with water until they bite. Installed them and then went up and down the nearest road with a decline several times braking until nearly stopped.

I have just taken the pads out and they have an almost mirror shine to them so not sure what’s going on.


 
Posted : 23/04/2021 10:42 pm
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I've got Uberbike Race matrix pads on my do it all bike.

They seem to have a slight high pitched noise until warm, but have so much more power and silent as soon as either you've braked for more than 5 metres.


 
Posted : 23/04/2021 11:00 pm
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Did the marshy rubbing together with water

The what now? 🤔

Installed them and then went up and down the nearest road with a decline several times braking until nearly stopped.

I ride down the nearest big hill pulling brake on and off quickly until you feel them getting progressively better, never come to a stop just pulse to get a quick heat and cool cycle into the pad and rotor. Braking to a stop will over heat and glaze the pad surface reducing performance.


 
Posted : 24/04/2021 12:37 am
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@rOcKeTdOg -


 
Posted : 24/04/2021 8:21 am
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Interesting but I think you've proved that makes no difference 🤷‍♂️


 
Posted : 24/04/2021 8:35 am