Issues with GRX brakes - anyone moved to RX4+ calipers ?

Purchased a pair of RX4+ calipers.

Hopefully they should arrive this week and I can get them fitted. Plan to use the existing rotors which are Ultegra.

Any tips to make sure they are as clean as can be?

I have IPA but any other tips ?
 
when i clean rotors, i wash them and scrub them in my parts cleaner, then rinse in water, leave to dry or dry with paper towel, then spray on disc brake cleaner, i usually use Fenwicks but to be fair the muc-off one i think is good, i started using that because i had a workshop size bottle that came with a workshop pack and frankly i think it's very good, after that has dried off if i am worried i sand the rotors.

to bed in the pads, wet the pads under a tap, rub pad surfaces together until they start biting on each other, dry pads with paper towel, fit to calipers, set up brake, take outside and ride around in circles with the brakes on a bit to bed them in.

i find this procedure works.
 
RX4+ calipers arrived. Very nicely as usual from Hope

Took the opportunity to strip and clean it a bit. New chain , cables etc.

Calipers on , not bad to bleed really by following the video. Makes a mess though which I’m glad im not using DOT.


Not sure the Rotors I have are a good match as they are Brake track is slightly too narrow for the pad. I’ll see how it goes tomorrow maybe on a ride.

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Need to be careful with which brake oil you use. I think Hope brakes (bought complete) use dot4. Think Sram use dot4 too but shimano (and magura) use mineral oil. You can't use dot4 in brakes made for mineral oil as it destroys the seals (but i think you can do the other way around) so glad to hear you are using mineral oil.
This is why Froome was using magura calipers as they use mineral oil too so an easy switch.
 
Hope and Sram use dot5.1. shimano and magura use mineral oil.

You know what they say about a little bit of knowledge is dangerous.

Take a look at my pics of the Hope calipers. You see the “M” on the bore of the caliper. Guess what that means?

(I’ll give you a clue the other version has a D)
 
You know what they say about manners; they cost nothing. The main point of my post was not to mix fluids and that I "thought" Hope use Dot fluid.

Hope have been making brakes with M on for years, (mono, M4 etc.) and they use dot brake fluid. I had a quick check of their website and they say they use dot5.1 but I'm not their tech support.
 
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