Particles in brake blocks- is this normal?


Legendary Member
A question for the more experienced roadies on here: is it normal for a brake block to pick up grit like this? Will this harm the rims?


The pads were like this when I got the bike; it had been ridden in filthy conditions. I dug out the worst bits and the rims on the Aksiums I used for 1200 miles don't seem to have suffered from gouging. You can see the ridge on this pad left by the wear indicator and yes, the pad position needs adjusting by a mm or so.

Now I have some lovely Ksyriums courtesy of AlanW here on CC. Have't actually ridden them more than 30 miles yet because I'm off the bike with dodgy knees but I worry that the bits of grit will score the rims.

What do you think? Time for a new set of pads?


Legendary Member
If there's enough meat in the shoes, i dig out the debris with the pointy bit of a stanley knife.
Definately dont want that in there, it'll gouge your rims...i know, it did on one of my previous bikes :wacko:

Winter or wet weather riding always seems to get cr@p into the blocks, i check mine regularly (yesterday in fact)

Fab Foodie

hanging-on in quiet desperation ...
Doesn't seem right to me, is there any 'scraping' sounds?

For my money and with good wheels I'd get some soft pads like Koolstop Salmons, better to wear the pads than rims, and I never seem to have any grittiness issues with them.
My pal's cheap blocks that came on his Campag Bianchi are full of unmentionable crud and it sounds like he's stopping with sandpaper against his rims. Makes me wince


Cycling in the sun
Surely for the cost of new blocks, and baring in mind the nice new rim, you may as well change them... as it is they look fairly moulded to the existing rim.


They are either picked up off the road in wet weather or the previous owner "cleaned" the rim with sandpaper at some stage.

I'd pick them out, lightly smooth the pad with very fine sandpaper then give it a wipe with a dry cloth to get rid of any debris.


Legendary Member
Thanks for the advice. I did pick some out but most of the grit is too deeply embedded - I'm going to order new.

(When I got the bike it was almost new but in a neglected condition; it had been ridden in winter salt and was filthy so I'm not surprised the blocks are full of grit)


Europe Endless
I've been using these ones from CRC for years and would recommend without hesitation. Irritatingly, the red ones come with a spare pair of black pads, but I usually have red at the front and black at the back.


Legendary Member
Globalti said:
A question for the more experienced roadies on here: is it normal for a brake block to pick up grit like this? Will this harm the rims?
It is normal if you use Shimano pads.
Yes, it does harm the rims. It's even possible for the rim to wear out faster than the tyre does.

It stopped happening when I switched pad brand (to Koolstop)


crappy member
South West
All brake blocks look like this after a while - it's normal but not good. That 'grit' is exactly that plus some alu particles from the rim itself.

Definitely worth digging them out quite often with the point of a knife blade as they will gouge the rim.


Über Member
Sorry to dig up an old thread! Just went to examine the brakes on my Carrera Subway and horrified to see that front and back rims (left and right) and gouged, and the brake pads are full of metallic particles. I assume the particles are bits of the rims!

I bought the bike from Halfords at Christmas, it has only done 500 miles, I will contact their Customer Service team to see if they can assist.


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