I'm quite confident I can change the pads, I'm actually relieved to discover they're worn, but I'm concerned about the clicking.
I'm conscious of the fact it's only the same noise as before and the Decathlon dude was convinced there was nowt wrong with the mech but obviously to see the potential for the wheel to suddenly click out of the grasp of the pad is the last thing I need when I'm already having anxiety going downhill.
Cable disc brake clicking when brake lever is pulled the full way back
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Re: Cable disc brake clicking when brake lever is pulled the full way back
Cable disc brakes work by having one moving pad and one fixed pad. The moving pad contacts the rotor and pushes the whole lot against the non-moving pad.doffcocker wrote: ↑25 Jan 2023, 4:50pm ... but obviously to see the potential for the wheel to suddenly click out of the grasp of the pad is the last thing I need when I'm already having anxiety going downhill.
What you've got there is the moving pad worn to bits and the non-moving worn partially (which is what usually happens) but I suspect you've tried to adjust them using the cable rather than the pad adjuster screw/knob.
Hence on braking, the system is over-camming and then releasing itself. It needs new pads bit it also needs a careful set up from scratch and then the new pads will need a few hard pulls to bed them in.
Hydros are different, both pistons move together and will self-centre.
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Re: Cable disc brake clicking when brake lever is pulled the full way back
Thank you.rareposter wrote: ↑25 Jan 2023, 4:57pmCable disc brakes work by having one moving pad and one fixed pad. The moving pad contacts the rotor and pushes the whole lot against the non-moving pad.doffcocker wrote: ↑25 Jan 2023, 4:50pm ... but obviously to see the potential for the wheel to suddenly click out of the grasp of the pad is the last thing I need when I'm already having anxiety going downhill.
What you've got there is the moving pad worn to bits and the non-moving worn partially (which is what usually happens) but I suspect you've tried to adjust them using the cable rather than the pad adjuster screw/knob.
Hence on braking, the system is over-camming and then releasing itself. It needs new pads bit it also needs a careful set up from scratch and then the new pads will need a few hard pulls to bed them in.
Hydros are different, both pistons move together and will self-centre.
I had booked this afternoon off to go on a long ride and as that hasn't worked out I'm instead trying to educate myself on how these things actually work as I've only previously dealt with rim brakes.
Unfortunately I can't find anything really on this type of mech.
It's the first time I have so much as removed the pads and I'm not confident about reassembling as with every video on YouTube, the mech looks very different. For example I have a silver clip that separates the two pads and I can't find anything that clearly shows how this needs to be positioned.
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Re: Cable disc brake clicking when brake lever is pulled the full way back
The owner's manual for those brakes is here:
https://s3.us-east-1.amazonaws.com/prom ... _V1_EN.pdf
The silver clip is a spring which helps force the pads apart once you've released the brake lever - it should just sit between the two pads.
Hint: if you're doing stuff like this again is to take a couple of photos before you touch anything so you can see how it all looks. If necessary, a photo at each stage of disassembly as well.
I would add though if you're at all unsure of anything, it's best to take it to a shop, especially with something as critical as brakes!
https://s3.us-east-1.amazonaws.com/prom ... _V1_EN.pdf
The silver clip is a spring which helps force the pads apart once you've released the brake lever - it should just sit between the two pads.
Hint: if you're doing stuff like this again is to take a couple of photos before you touch anything so you can see how it all looks. If necessary, a photo at each stage of disassembly as well.
I would add though if you're at all unsure of anything, it's best to take it to a shop, especially with something as critical as brakes!
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Re: Cable disc brake clicking when brake lever is pulled the full way back
The 'rivets' I mention are actually just the bonding points for the backing and are a 'telltale' and shows the wear well before the pad gets to the metal (in theory) but as you say his cable tightening instead of just using the proper adjuster has killed that pad, and very early at that judging by the good one. The telltale idea is similar to the telltale in a rim pad (or the rim itself).531colin wrote: ↑25 Jan 2023, 4:12pm friction material is bonded onto the backing (not riveted) and you are recommended to fit new pads while enough friction material remains to stop the heat from braking melting the bond.
i imagine the brake is coming to the end of its travel (over-camming, as before) and releasing the disc
Re: Cable disc brake clicking when brake lever is pulled the full way back
Not all cable disc brakes, e.g. TRP Spyre.rareposter wrote: ↑25 Jan 2023, 4:57pmCable disc brakes work by having one moving pad and one fixed pad. The moving pad contacts the rotor and pushes the whole lot against the non-moving pad.doffcocker wrote: ↑25 Jan 2023, 4:50pm ... but obviously to see the potential for the wheel to suddenly click out of the grasp of the pad is the last thing I need when I'm already having anxiety going downhill.
What you've got there is the moving pad worn to bits and the non-moving worn partially (which is what usually happens) but I suspect you've tried to adjust them using the cable rather than the pad adjuster screw/knob.
Hence on braking, the system is over-camming and then releasing itself. It needs new pads bit it also needs a careful set up from scratch and then the new pads will need a few hard pulls to bed them in.
Hydros are different, both pistons move together and will self-centre.
This is from https://trpcycling.com/product/spyre-2/
"This is a dual piston actuated mechanical disc brake caliper which provides precise clamping force. This translates into even pad and rotor wear"
Richard M
Cardiff
Cardiff
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Re: Cable disc brake clicking when brake lever is pulled the full way back
I took everyone's advice, played it safe and booked a check up at Decathlon.
The guy who checked it this time was quite alarmed at how worn the pads were.
I showed him the videos of what sometimes happens where the brakes make a loud bang before failing. He said this could be due to a number of things - not gonna lie his English wasn't great so I couldn't understand exactly what he was saying but he explained a scenario that involved the brakes somehow causing spokes to generate that noise which actually makes sense in that it is very much the kind of sound you get from spokes. (If that makes sense...)
Anyway I went away with some new brake pads so fingers crossed I manage to put this right myself.
The guy who checked it this time was quite alarmed at how worn the pads were.
I showed him the videos of what sometimes happens where the brakes make a loud bang before failing. He said this could be due to a number of things - not gonna lie his English wasn't great so I couldn't understand exactly what he was saying but he explained a scenario that involved the brakes somehow causing spokes to generate that noise which actually makes sense in that it is very much the kind of sound you get from spokes. (If that makes sense...)
Anyway I went away with some new brake pads so fingers crossed I manage to put this right myself.