Problems with Shimano Disk Brake Brake Pads.

[Tom B]

This is getting annoying. I've just lost the friction material off another brake pad. It's not worn away, it's broken off the backing plate and been ejected out of the caliper.

*The good pad in the picture is not the other pad from the pair it's one that's been kicking around my box of bits for a few years.

The Pad type is G01S, I think there is an alternative upgraded version but the pad choice is frankly befuddling for the BR-M615 caliper.

In the last few months I have suffered 4 failure of this nature. First couple I put down to a one offs /bad batch, another I put down to the pads perhaps being counterfeit as I bought them from an unknown to me eretailer, and then it has just happened again. Pads are 6weeks old approx 750miles, a fair bit with the little lad but I've not really been taking him on any big hills - more old railway lines, Camel Trail, Bissoe Trail, Glasson Docks to Carnforth Via Lancaster, Morecambe and Heysham etc as well as nursery trips.

Thanks to saving in damaged and any half decent worn pads and a set of uberpads I didn't like I've been able to bodge up some sets to keep me going.

The only thing I have changed is a out 8 months ago I moved to a 180mm disk as I was cooking up the 160s stopping for junctions down the big hills when I had a full load (rucksack) of shopping and child (2year old in a rear seat). The extra "grab" presumably provided by the extra leverage on the 180mm is noticeable (and suprised me) and took a bit of getting used to but now I blend them just like any others.

The only other defect I have a crack in the reservoir bleedcap body that weeps but lasts possibly 12months before needing topping up.

I buy OEM Shimano pads because I like the feel and to avoid this sort of issue.

Has anyone had similar failures?

Any suggestions?

*I have but in some part used uberbike resin pads which I didn't like when I bought them. I thought they felt gritty and were noisey. But we've done from Barton upon Humber to Hornsea and back today and they felt fine. So I might give them another go.

 

[si_c]

Only ever had that at the end of the pad life when I'd used them beyond the minimum level. Try Noah & Theo pads - they're very cheap and very good. If you want to improve the stopping power and have better heat control get some ceramic ones.

 

[DRM]

Perhaps the extra forces caused by using 180mm discs on a heavily loaded bike, are overheating the bonding, then pulling the friction material from the backing plate, bigger discs will have more stopping power, perhaps a brand like EBC may be better as they do make motorbike pads.

 

[Tom B]

Perhaps the extra forces caused by using 180mm discs on a heavily loaded bike, are overheating the bonding, then pulling the friction material from the backing plate, bigger discs will have more stopping power, perhaps a brand like EBC may be better as they do make motorbike pads.

Pretty much my thoughts. Though the heat problem is much less of an issue than with the 160mm.

I've ordered some of the ceramic pads mentioned by the previous poster.

The wheel is fitted with a centre lock rotor (came with the bargain wheel) which if I stand still and apply the brake hard I find I can rock the bike slightly on the brake. Seems to be coming from splines between the rotor and hub. Is this normal for centrelock - I've nothing to compare it to.

I was wondering if this would cause an imperceptible snatch as I apply the brake which is giving the pads a hard time.

 

[DRM]

Pretty much my thoughts. Though the heat problem is much less of an issue than with the 160mm.

I've ordered some of the ceramic pads mentioned by the previous poster.

The wheel is fitted with a centre lock rotor (came with the bargain wheel) which if I stand still and apply the brake hard I find I can rock the bike slightly on the brake. Seems to be coming from splines between the rotor and hub. Is this normal for centrelock - I've nothing to compare it to.

I was wondering if this would cause an imperceptible snatch as I apply the brake which is giving the pads a hard time.

I can’t comment with regard to a centerlock disc as mine has 6 bolt discs, with mechanical TRP Spyres, however I’ve noticed that it too has the ability to rock the bike with the front brake applied, I’ve seen it’s the pads moving in the callipers slightly, again it may have something to do with your problem, but it’s not something I’ve had on either the MTB or gravel bike

 

[wafter]

Pretty much my thoughts. Though the heat problem is much less of an issue than with the 160mm.

I've ordered some of the ceramic pads mentioned by the previous poster.

The wheel is fitted with a centre lock rotor (came with the bargain wheel) which if I stand still and apply the brake hard I find I can rock the bike slightly on the brake. Seems to be coming from splines between the rotor and hub. Is this normal for centrelock - I've nothing to compare it to.

I was wondering if this would cause an imperceptible snatch as I apply the brake which is giving the pads a hard time.

If the larger disc is causing an issue it'll be due to relative velocity not force; since the greater leverage of the larger disc will require less force at the pad to exert a given stopping torque at the axle.

Can't say for certain but the play in the disc might have something to do with it - perhaps some strange oscillating effect - do you notice any oddness to the feel at the fork when braking - juddering etc? Is there play in both front and rear disc mounts or just the front?

I have centrelocks on my CdF and don't notice any play (nor should there be any IMO) however do get some oscillation at the front under heavier braking that seems to phase in and out with speed (my assumption was that it was a poorly-bedded disc hitting the natural frequency of the fork).

I've not noticed any issues with the pads, but then I tend to be fairly gentle on my brakes.

 

[Tom B]

If the larger disc is causing an issue it'll be due to relative velocity not force; since the greater leverage of the larger disc will require less force at the pad to exert a given stopping torque at the axle.

Fair point. My loosely worded op wasn't my finest work .... Blame beer.

Can't say for certain but the play in the disc might have something to do with it - perhaps some strange oscillating effect - do you notice any oddness to the feel at the fork when braking - juddering etc? Is there play in both front and rear disc mounts or just the front?

I have centrelocks on my CdF and don't notice any play (nor should there be any IMO) however do get some oscillation at the front under heavier braking that seems to phase in and out with speed (my assumption was that it was a poorly-bedded disc hitting the natural frequency of the fork).

I've not noticed any issues with the pads, but then I tend to be fairly gentle on my brakes.

Absolutely no weirdness in normal operation it's actually got a really nice feel and balance which is the reason I don't really want to change much.

The bike is filthy after a few weeks near the coast and flying around old railway tracks I'm going to give it a full wheels out clean in Sunday and see if I can track down the rock. Ive tried a spare 6 hole disk wheel in and don't recall any rock.

 

[recumbentpanda]

I run centerlock discs. There should absolutely be no movement whatever. Some caliper types however, do allow the pads to move a little forward and backward. If you hold either brake on and rock the bike to and fro, that is noticeable play. If the pads have been rocked back, you may hear a click when applying the brakes the first time after a stop.

 

[Tom B]

Had a quick clean yesterday but not the wheels out job I was expecting. The movement is definitely between the disk and hub. I can move the disk relative to the wheel by hand.

Needs further investigation.

 

[fossyant]

Had a quick clean yesterday but not the wheels out job I was expecting. The movement is definitely between the disk and hub. I can move the disk relative to the wheel by hand.

Needs further investigation.

Get that fixed before the dentist is your best mate !

I can recommend Uber Bikes pads - I run Race Matrix on my Trail bike and sintered on MrsF's.

 

[figbat]

Had a quick clean yesterday but not the wheels out job I was expecting. The movement is definitely between the disk and hub. I can move the disk relative to the wheel by hand.

Needs further investigation.

Definitely - discs should be rigidly attached to hubs. I can't see how this would cause the original issue though.

 

[recumbentpanda]

You will need the centerlock special tool to tighten them. I believe it is the same as the Shimano freewheel tool. Because the Centrelock locking ring has ‘friction splines’ the feeling when tightening it will be ‘notchy’. Tighten until it will not go another notch.