Anyone know anything about disc brakes?

Getting some bad braking chatter on my front brake, cannot for the life of me get rid of it. 223mm TRP 2.3mm thick rotor, Hope E4 caliper, generic sintered pads. There's no rubbing that I can see or hear, the pad clearance is very tight though. Caliper is totally centred, pads hit simultaneously with a very nice noise. But hard braking it judders badly, like you can feel every rotor vent. Rotor totally true, and I've sanded it back a few times to get rid of any brake deposits...

have you tried yoga?

The thick dairy stuff you eat with a spoon?

Can you chuck on another rotor and see if it still happens?

Its worked fine before, same setup. Only difference is I changed the caliper seals and pistons recently

disc brakes are pure homeopathy after a certain point, just embrace the rub

Change pads

My rear 105 caliper must leak somewhere, me and local mechanic tried everything and it still howls and loses power. Would you swap for a new 105 (£45) or something like a Hope (£85) or anything else?

New 105

I’d switch to a caliper that can be serviced(rx4) rather than another shimano caliper.

Same. You can keep Hope's running indefinitely, it's worth the extra initial outlay

Just embrace the close clearance rub.

Getting some bad braking chatter on my front brake, cannot for the life of me get rid of it. 223mm TRP 2.3mm thick rotor…

223mm Rotor? Is that some kind of tandem downhill cargo bike that needs rotors that big?

Just your regular old enduro-bro sled

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I bet a smaller diameter rotor would be stiffer.

Going on anecdotal evidence of how much harder it is to true compared to 1.8mm 203mm rotors, I'm not so sure.
Either way, it's previously worked fine. I might change pads, see if that helps.

Or use the brakes less.

A few years ago I experienced the exact same judder on the front brake on my road bike. I couldn't get to the bottom of it, multiple bleeds, sanded pads and rotors and it still happened. It only stopped when I replaced the rotor and pads :( it was annoying not fully knowing how/why it was happening.

@M_V smaller rotors is obvs technically going to be stiffer but the 220mm+ rotors are thicker (2.0mm - 2.3mm). I use 220m rotors on my mtb and theres no more rub than on a 200 rotor. The extra power is great for my current 101kg dad bod...

Just embrace the close clearance rub

I'm assuming that you're talking about the rx4's?
It is worth noting that they definitely do take way more effort to set up correctly but it's not impossible to have them running without any rub. If you're the type who does all the work on your own bikes and have the time to set them up they are great.

Yep the rx4 and 160 rotors . I think its just the close tight bend on the columbus forks.
The back is fine . Still the best brakes i have had.

@TotalShanner @TooTallTim fair enough. My experience of larger rotors was that they rubbed a lot more/buckled a lot more easily but I was only going to 180/203mm so standard width I’d assume.

what hope brakes are these? they say x2 on caliper but googling that gives me multiple versions/years

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Looks like the 2007ish era stuff.
Maybe the mono mini https://www.hopetech.com/product-documents/brakes/#!2007-mono-mini-brake

edit - its actually the 2009 mono mini pro that used an 09 x2 caliper and the o7 mini lever

ah cool! thanks! I think the pads are the common x2 pads .. bleed seems straightforward when it will need, never had hope brakes on mtb, they seem to work fine

Yeah x2 pads. I haven't used Hope mtb brakes since around this era, nice kit.
Hope are pretty helpful with getting old brakes going again, my pal sent them an old set of a similar vintage and they rebuilt them and sent them back working for not much cash.

the top cap on the lever reservoir says DOT fluid only! I didnt know Hope made DOT brakes, I thought they were always mineral.