Durace rim brakes

[Lookrider]

Hi all
I recently had a brake issue on a long decent
I looked at brakes myself and it appears the brakes have came loose via the single "spindel" secured through the forks
I seen shimano docs for similar 9000 series but mine are 7850 ( I think ) series ...but on that I re tightened to a little less than specified torque
Now 2 things I'm curious about and need guided on please

As this is a single spindel what can stop it from rotating as there is no other pins in as such to prevent this

Also there is a small grub screw on a black "washer "
Again what is this fur as there seems no flats on the spindel for this to but up against

And is the location of this grub screw of importance
Ie looking from front should it be at 12o/c ..3o/c or 9o/c

I cannot locate any blow up PDFs for this series brakes on shimano docs

 

[Gunk]

They are dual pivot brakes and the bolt just retains the spring and attaches the calliper to the frame or forks. As there is very little force on the retaining bolt when braking it doesn’t need to be over tightened.

 

[Lookrider]

Thanks for that prompt reply gunk
As there dual pivots I can see how theres little force on the spindel as both pads are in contact with rims at same time

I did hear a kind of crack at time but I now guess that was the spindel turning through the fork holes ?
The spindel did come loose somehow though
This may have been as the wheel warped ( not really buckled ) and maybe that offset on the rim forced the one pad too far over thus turning the spindle ?
So do you think theres something more sinister lurking behind there on the forks around the securing holes ?
It does seems robust now
If you look carefully theres a little paint damage on the spindle fork interface ...I dont know if this was when the spindel turned and took the paint with it..or if it's just a little rain corrosion

I'm going to get new pads anyways but curious if the pads have any form of wear indicater dimples or such so you know there beyond there life

 

[neil_merseyside]

Pads normally have water clearing grooves so when they (are about to) disappear you replace them. Those pads look shot, if you have to adjust cable pull more than twice you probably need new pads.

 

[si_c]

The grub screw is just a set screw to ensure the bolt doesn't move and keeps the brake assembly in place. It has nothing to do with centering the caliper. This is done using the allen bolt on the top right of the brake as you look at it from the front - it adjusts the spring tension and thus the relative position of the brake arms at rest.

 

[Lookrider]

Niel
Theres still a good deal left on the water grooves
Do you know what the grub acrew is for

 

[si_c]

I'm going to get new pads anyways but curious if the pads have any form of wear indicater dimples or such so you know there beyond there life

As @neil_merseyside says above the pads should have grooves to allow water to escape when braking in the wet, once these have gone, replace the pads.

 

[fossyant]

The grub screw on the 'arms' adjusts where the arms sit - you can align them. TBH never used it, as I align the brakes using a cone spanner just in front of the fork.

 

[Lookrider]

I'm getting new pads anyways even though there still lots in the grooves

Just to clarify as well
The pads have been removed from the photo ....

 

[Lookrider]

Just for reference regarding pad wear indicators
I'm not convinced the water grooves are also indicators to wear as the water grooves on these pads go all tbe way down

 

[si_c]

Just for reference regarding pad wear indicators
I'm not convinced the water grooves are also indicators to wear as the water grooves on these pads go all tbe way down

They look pretty similar to those I have, the grooves reach the area just above where the pad would disappear into the shoe so replacing them at or before that point will prevent the pad wearing too thin and then the metal brake shoe contacting the rim.

 

[Lookrider]

Yes interesting
I didn't want anyone abusing the life and safety of brake pads if they are thinking water grooves are an indicator
I not be surprised if manufacturers have stopped doing indicators maybe in past some body got injured but then cited ....well me pads were ok as the indicators still on so blame them
Remove the indicators then it's down to oneself to have safe brakes and not a manufacturer responsibility

Thanks for the replies gents