I’ve got a feeling my rear road Shimano caliper (flat mount) is on its way out with seal issues. Apart from fairly normal ish squealing in mucky weather they’ve always been fairly quiet and just strong and reliable.

The last few rides the rear brake has been making an awful noise for the first few stops – and it’s not even been wet / mucky out. I’ve tried cleaning up the pads but they weren’t even that old Tbf. I haven’t tried jamming in some kitchen towel and leaving it overnight to check for micro leaks but if this carries on its new caliper time I feel.

Had my eye on the Hope RX4 road calipers – I have flat mount rear mounts and a 160mm Shimano rotor.

Other than the Hope caliper is there anything else I need or will the existing hose / fittings fit the Hope?

The bike has 105 level brakes (flat mount rear / post mount front) with finned pads right now.

I did the same thing with some ultegra callipers. Wished I’d never bothered they were rubbish and howled from day one (yes different pads/rotors) I tried everything. Basically it was awful and they look like something Massey Ferguson would concoct.
Avoid imo

Avoid the Hope calipers you mean – or something else?

Most stuff I’ve read about the RX4’s is that they are decent….

To counter – I thought my Hope RX4’s were brilliant, much better feel than the Shimano calipers, flawless reliability and look ace.

Everything is in the box to connect them, but you’ll need to bleed them.

Make sure you get the mineral oil calipers!

I’m hoping to go Hope RX4 on my new build. I have also read some bad stuff -considering the price. Any other alternatives?

I’ve got a Shimano bleed kit (well – epic bleed solutions for Shimano) as I changed the 105 non series levers for Ultegra di2 ones just under a year ago.

So as long as the new caliper bolts on ok and the fittings are the same I should be able to do the job myself.

I’ve got a gunmetal and blue 2017 Casd12 disc so the sensible colour to go for is black. But wondering about another colour to jazz the bike up a bit – but don’t want it to look ridiculous. Plus I’m loathe to buy a front post mount caliper as if I swap frames in time it’s bound them to be flat mount front as well as rear.

Really like the look of the aftermarket gold finger yellow caad13 – plus that has proper mudguard mounts and more clearance for slightly bigger tyres. Wife might kill me if I buy one at the moment though…..

Mine are awesome.

Plenty of modulation and stopping power.

A bit of a squeal when wet/cold but that soon goes away.

Genuine Hope pads and Hope CL road rotors by the way.

If anyone’s switching to RX4s on the front, bear in mind that the hose connector is angled towards the fork blade. The forks on my bike (Mason Definition) curve inwards above the caliper, which has meant it’s impossible to get the RX4 caliper lined up with with rotor. Probably not a problem on the vast majority of bikes, but hopefully this might save someone some hassle and cash.

So far my front caliper is ok so hope (no pun intended) I don’t need to change that one for a while yet given the cost of RX4 and faff of changing calipers and bleeding etc!

RX4’s are awesome. I upgraded form my 105 setup including with Hope floating rotors and it is much better. All the required fittings come in the box as well as a set of organic and sintered pads. I fitted the organics first as I prefer those on my MTB but the sintered pads are actually better on the road bike. I just got my LBS to fit as I didn’t have the bleed kit and was less faff and no more expensive just to get the LBS to install.

As has already been said, make sure you get the mineral fluid version.

Will do on the mineral version – will wait until next pay day before buying a new caliper as I’m not in a huge hurry and just finished buying bits for my new hardtail build.

Probably will just get a black one as I think all the other colours are too bold / the silver is a bit retro.

My Shimano brakes came with sintered it seems – I bought new pads last year and accidentally bought organics. I think the sintered pads were better tbh – they seemed to have a firmer brake lever consistently down steep / fast tarmac descents. I don’t find the organics so good.

To counter – I thought my Hope RX4’s were brilliant, much better feel than the Shimano calipers, flawless reliability and look ace.

+1, I’ve been very happy with mine. Very little noise, too.

The forks on my bike (Mason Definition) curve inwards above the caliper, which has meant it’s impossible to get the RX4 caliper lined up with with rotor.

I have a Definition but didn’t have this problem.

+1, I’ve been very happy with mine. Very little noise, too.

yeah, mine have been ace too. Swapped from SRAM rather than Shimano though, and couldn’t use flat mount due to the age of my frame, had to bodge with various mounts/washers out the spares kit as the correct one wasn’t actually available from Hope! (this was when they first came out. Not sure if they do the proper mount now. Wouldn’t have been an issue with flat mount)

I have a Definition but didn’t have this problem.

That’s interesting – which version of the fork is yours? Mine’s the flat mount, thru-axle version. I guess the rotor (Shimano centre lock) and hub (Hope RS4) also matters.

That’s interesting – which version of the fork is yours? Mine’s the flat mount, thru-axle version. I guess the rotor (Shimano centre lock) and hub (Hope RS4) also matters.

It’s the mk1 post mount, 6-bolt rotor and Novatec hub. Though I do have a mk2 fork with flat to post mount adaptor ready to fit… will be interesting to see how that goes!