Calliper Arm Movement?

bpsmith

Veteran
Have swapped the pads from 105 front calliper into my FSA Gossamer front calliper to test on different bike. Pads are way better in fairness.

The downside is that the right calliper arm is moving forward initially when first braking. Appears to be twisting slightly within range of the gap between the arms at top. Not sure if it has always done this and now just noticing or if it's down to the grippier pads?

Anyone else experience this on their road bikes?
 

accountantpete

Legendary Member
Photo Winner
There should be no movement - the right arm (I think) pivots on the central spindle and the left arm pivots on the end of the right arm.

If you have movement in just one arm it means that the pivot area for that arm has worked loose from use.

I don't know that brake but usually there is a locknut/ grub screw to keep everything in place and then another nut - undo the locking nut and then tighten up so that there is no play and then re-tighten the locknut/grub screw.
 
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bpsmith

Veteran
There should be no movement - the right arm (I think) pivots on the central spindle and the left arm pivots on the end of the right arm.

If you have movement in just one arm it means that the pivot area for that arm has worked loose from use.

I don't know that brake but usually there is a locknut/ grub screw to keep everything in place and then another nut - undo the locking nut and then tighten up so that there is no play and then re-tighten the locknut/grub screw.
That was my assumption. Couldn't see anywhere to tighten it up other than the usual mounting and cable points. Will remove it and check again later, cheers.
 
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bpsmith

Veteran
I took my FSA caliper apart to find out how it works. It's in 3 main pieces. The part that mounts to the bike, then the right arm and finally the left arm.

I had to remove the left arm first, in order to reveal an Allen bolt behind at the centre of the fight arm. Loosened the tiny retaining bolt and then held a shifter on the nut, whilst tightening the Allen bolt. Tightened retaining lock bolt onto bolt thread at the nut. Then did the same refitting the left arm.

Looks solid at face value, but not test ridden yet as brake cable was notchy, before this, and found the inner has rusted a bit and frayed where it enters the caliper. New cable tomorrow and then testing on the weekend.
 
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bpsmith

Veteran
As above, it is the right arm only. Right arm being as sat on the book and how Shimano describe it.

Got it sorted now, as replied above, and will test tomorrow after reaching the cable inner and outer as got a fray and some rust on the cable too.
 

accountantpete

Legendary Member
Photo Winner
Funny that, I've just removed a 105 caliper because of the same problem. I've only had a quick inspection but I'm buggered if I can see anything to tighten up.
With shimano you probably have a starred shaped locknut at the back.

I'm just dismantling some Ultegra 6600's and this is the procedure:

Undo this nut slightly - use pliers with teeth etc.

Then look underneath and you will see a grub screw which holds the left arm in position on the spindle.

Undo the grub screw.

Then using a Torx screwdriver tighten up the arm to remove play - the torx goes into the nut at the front of the arm.

Then tighten up grub screw and locknut and your done.
 

Smokin Joe

Legendary Member
Cheers, I'll try that tomorrow.
 
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bpsmith

Veteran
Happy to report that short test on my hill has proven that the tightening up was well worth it.

Brakes are now equally as good, better if anything, than the new 105's I fitted to the winter. That's with the 105 pads fitted, so fair comparison.
 
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