Front brake making ...
 

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Front brake making Thunk,Thunk,Thunk noise

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On braking the fronts making this noise.Its fine off the lever, only when actually braking and performance slightly affected but maybe thats just me thinking because the noise is annoying.

Any ideas what it might be.?

Pads replaced recently, in fact the last set lasted nearly a year and these are only a couple of months old so not a pad wear issue. Thought maybe the rotor is worn but not something ive encountered before so ive no idea.

Shimano 4 pot brake, shimano rotor. centerings fine.

 
Posted : 16/01/2023 8:16 pm
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rotor worn and you are hearing the noise of the pads hitting the arms?  You might be able to push the bike with the brake pulled lightly to see if that is what is happening

 
Posted : 16/01/2023 8:28 pm
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Check the rotor very carefully to make sure there’s no damage to it, very small imperfection on the actual braking surface or edges of it could cause that. Do you have another wheel to try..? I guess not as you probably would have thought of that already 🙂.

 
Posted : 16/01/2023 8:36 pm
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rotor worn and you are hearing the noise of the pads hitting the arms?

Yeah that sounds most probable to me, would account for the spacing. I'll look for a new rotor.

Cheers 🙂

I guess not as you probably would have thought of that already 🙂.

Yeah, I've only got one spare wheel and its got one of the extra thick HD hope rotors on it. But the above worn rotor sounds more like the problem, the spacing indicating hitting the arms.

But again, cheers for taking the time to reply 🙂

 
Posted : 16/01/2023 9:08 pm
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Unless some part(s) of these are newly fitted I don't see how pads are "newly" hitting the arms.  Surely if they overlap the arms now, they always did (and would wear with the pads) ??

or am I wrong again ?

 
Posted : 16/01/2023 10:03 pm
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Just a thought, and unlikely seeing who has posted the query: have you checked that all the calliper bolts are all tight? Also the QR?

Or check for a shiny patch on the disc rim in case it's slightly out of concentric. I've seen that on some Avid disks. A skinny washer under the calliper bolts to fractionally raise the calliper fixed that.

 
Posted : 16/01/2023 11:44 pm
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Yeah bolts are solid, and the pads are a few months old and worked fine, this prob has appeared in the last couple of days.

TBH I havent a clue. It certainly sounded like the answer was the arms, but looking now in bright light it doesnt look like the pads go that far down.

I suppose I could remove the pads, file down the leading edges and give the whole system a good scrub.

I'm actually being lazy. Ive got new pro 4 wheels and new tech 4 brakes but i havent got around to fitting them. I think im just a bit down/depressed and the joy of it all has worn thin. Normally I'd have new stuff fitted the day i got it, not left in the box.. 😕

 
Posted : 17/01/2023 12:27 am
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Some other thoughts. Warped disc, loose headset, loose axle. I had the same sort of noise and it was a warped disc.

 
Posted : 17/01/2023 12:45 am
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Pad spring catching the rotor?
I’ve had this when they weren’t properly in place round the pads when I rushed a change.

 
Posted : 17/01/2023 7:44 am
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Check your hub - I've had a cracked one which opened under braking and made an odd noise.

 
Posted : 17/01/2023 7:52 am
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Are the rotor bolts loose ?

 
Posted : 17/01/2023 2:29 pm
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And another thought - if they are suspension forks, have you checked the bushings and legs for movement/flutter?

 
Posted : 17/01/2023 2:36 pm

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