Shimano Tiagra rear brake trouble

jackcf

Hi people,

I have been having some issues with my rear brake on my road bike

I noticed that it was not releasing after pressure was being applied, so I removed it, washed it w/hot soapy water to get all the grit out, dismantled it, lubed it up and put it back together. Everything looked fine, as it was now springing back to its original position after being squeezed. See video HERE. Photos of brake HERE and HERE

But having put it back on my bike it is still not releasing...

I think it might be the bolt that attaches the brake to the frame. It seems by the time I tighten it enough so it doesn't wobble from side to side, it is too tight to let the components of the brake move freely? I can't work out why it's doing this..

Am I doing something wrong or is it just time to buy a new set?

keezx

Do the arms move free without the spring?
If so, there should not be a problem unless the outer cable is too short or too long.

BTW, it seems that the mounting bolt is also 1 pivot bolt (like the old single pivot brakes) so you might have made an error with reassembling the brake.

BTW 2 buying a new set is the same as buying a new car because the ashtray is full....

wongataa

Have a look at the Shimano tech docs on their website. There should be one for the brakes which should give some idea how they go together and work.

jackcf

Keezx wrote:

Do the arms move free without the spring?
If so, there should not be a problem unless the outer cable is too short or too long.

BTW, it seems that the mounting bolt is also 1 pivot bolt (like the old single pivot brakes) so you might have made an error with reassembling the brake.

BTW 2 buying a new set is the same as buying a new car because the ashtray is full....

The arms move freely when not attached to the bike and the cable/housing is all the same length as when it was working fine.

Yeah I don't want to buy a new one, I'm hoping someone can shed some light on the problem.

keezx

If you squeeze the brake (manual at the pads,without cable) and let it go and it springs back, then it must be in the cable(s) or brake lever.

jackcf

I just took it apart and put it back together again and now it's working. :oops:

So I don't know why it wasn't working in the first place and I'm not sure what I did differently when I put it back together for the second time, so all in all not very satisfying. But at least it's working again. I just hope it stays that way.

Thanks for your help guys.

k-dog

Probably just gummed up - common this time of year. A good clean usually does it - next time you can probably just remove the wheel and squeeze the pads together and spray lube on and open and close it. Removing the wheel means you can obviously squeeze the brake a lot further. Best to remove the pads too.

Mudguards have also solved that for me - stops all the crap getting in that area.