Has anyone had a good experience with Hope RX4+ calipers? I got a set so I could pair them with AXS electronic shifters on my ageing cross bikes with post mount and I must say what a miserable out of the box experience.
After getting everything bled up I thought things had gone well but after waiting a few minutes I swap on some new rotors and by the time I put it in the bike the rear caliper is leaking at the piston and the front runs so razor tight to the rotor that I can only imagine the drag during a muddy cross race.
Rather than fret about this all CX season I’m already thinking about alternatives to mount up on my post mounts - either downgrading to SRAM Level T or putting some flat mount calipers on Wolf Tooth Adapters
I’ve got RX4+ on both my cross bike and my road bike, paired with sram rival mechanical shifters. They’ve been excellent, great modulation and power. I’ve had then for about three years maybe, and not had any issues with leaks. There can be a bit of rub, especially with new pads, but it usually seems to solve itself quite quickly. I find lining the caliper up straight is the most important thing.
The main issue that I have is that the pistons need cleaning now and then, or they tend to get sticky. (Never even once cleaned the pistons on the sram calipers in 5+ years).
Thanks @splash do you home mechanic them or did a shop fit and look after them? I’m wondering if I managed to make a mistake during the initial bleed (not sure what) so I’m going to take them to a shop that has a lot of experience with Hope to see what they think before I throw in the towel
I installed them myself. I do all of the work on my bikes myself, but it was the first time I had changed brake calipers. I can’t remember any major issues. Think I needed to bleed them quite thoroughly to get the air out.
To be honest, if the caliper is leaking at the piston, I think the seal might have moved, or it is just faulty. You did get the right calipers for your brake fluid, right? If you’re on Shimano, there should be an “M” on it.
Thanks Splash, I called Hope today and shared some photos and they think the piston / seal is faulty so they have offered me a replacement, so bad luck on my part
How do the Hope calipers compare to the orignal SRAM calipers? Someone on a ride I was on recently had these Hope RX4 calipers and it got me wondering about upgrading. Is it a big difference?
EDIT: FWIW I’m using 160mm rotors. I’m guessing the biggest difference is more power with the 4 piston calipers vs 2 piston. Did you notice anything with regards to heat dissipation on steep & long descents?
I think they have better modulation and more power. When I swap from the bike with Hope brakes to the one with Sram brakes, I always have a “oh sh… , need to brake more” moment.
Not sure about long descents and heat - we don’t really have any descents over a few minutes. I’d guess that it has more to do with the rotor though, than the caliper. (And the pads - Hope have a chart for their different pad types).
Thanks. Yeah - I’d imagine rotor size/mass makes a much bigger difference to heat management than the caliper - but I was just wondering. I’m mostly concerned about heat build up on very steep (>15%) descents) so maybe I should try 180mm rotors first - which will also give me a bit more power with the stock calipers!
I have two sets of RX4+ (both shimano, though). The second set had a twisted piston seal. Replacing it fixed the leak. It would bleed and test fine in the stand, but would leak and foul pads and rotors on the first ride.
Once bled and in operation I’ve been happy, but I think the mineral and dot versions are significantly different. They do need occasional cleaning and pad clearance is on the thin side.
I have a few of the calipers (all on shimano systems) and while they’re a bit more involved to bleed they’re a lot less prone to the dreaded shimano micro leak. I did have one that leaked when I installed it but hopes customer service were phenomenal and I had a replacement in a matter of days.
Honestly rx4s are bling and shit and I have xcrs on my xc bike and e4s on my enduro bike, but they’re just more hassle than they are worth for road. I don’t think hope got the market penetration they were after and so it’s not been a well invested in / updated platform. Suspect it may end up as a stub. A lot of what makes hope brakes great is the master cylinder interaction which for road / gravel is always going to be third party and they can’t well accommodate for that or design it as a system (eg Shimano levers use servo wave, SRAM are linear).
I’ve got a pair to work for a while and well, they work great. Just like other road disc brakes. Until they don’t after 3 months and I have to spend a load of time fettling not riding. Fools errand.