Author Topic: Continuation: IIIPRO E4 4-Piston Hydraulic MTB Brakes - Are they to be trusted?  (Read 35935 times)

Fat Larry

If you find a fix i'd be tempted to buy a set. Still love the way these look. The silver looks great and the new orange and grey version is also appealing.

danielG169

Thanks a lot for your research! In a way, it would be a bit of a silver lining for these to be bad due to an engineering issue and not production issues.

Skepsist

Do the Speedone versions have ceramic pistons?? I saw a white piston in their promo shots.

It looks like the Speedone Soldier 2 (IIIPro E4) actually has ceramic pistons.
At least they look and feel like ceramic. The new IIIPro R2X4 has the exact same caliper with the same pistons.
As i said, did not have any problems with those and ive been using them for a year on a trials bike so no light use but also not getting very warm. And i also use ZTTO 2.3mm discs (wich i highly recommend) so i guess heat management is no issue for me. Dont know if bikepark or ebike use may be different.
Enduro+Trials Rider

Skepsist

So i got to use the R2X4 brakes today. Using the included finned brake pads which are probably semi-metallic. After a short brake-in-period they developed massiv power.
Usually i run 203mm Rotors but i dont think i need them with these brakes as they are simply very powerful so i'll stick to the 180mm that where included. The best comparison would probably be Magura MT5. Both in power and modulation.
Tough the IIIPro levers feel better and don't have as much resistance. The lever is very smooth but i had no issues with and without gloves. The IIIPro E4 levers are not even close i terms of comfort.
I will be using them until they fail, take them to some bikeparks check for thermal issues with a thermal camera. Not very scientific but i cooked some magura brakes before which was fun.

L-Twoo TX shifting was a bad choice tough but i'll write something about that in another post once i find out why its sucks so much.
Enduro+Trials Rider

Tijoe

It appears, and has been confirmed by you guys, that the latest versions of what was the E4 calipers have ceramic pistons in them.  The R2X4 and the Speedone Soldier 2 both have ceramic pistons.  I wrote the "Bolany Store" and the confirmed that they are indeed ceramic on the Speedone Soldier.   I asked if they have ceramic piston rebuild kits. or even seals, and they responded,  No seal or piston kits available.  (This will eventually become an issue.)

I scrutinized the caliper images posted in the R2X4 brakes in the listing below.  Looking closely at one of my E4 calipers, compared to the caliper shown in the R2X4 calipers, the R2X4 caliper machined bodies appear to be the same as the 2nd gen E4s that added the second bleed port.  The spacing of the pistons and diameter appear to be the same.  (16mm pistons.)    This would imply to me that if the new R2X4s actually have more braking force, it has to be a change in the lever piston assembly.   (Calipers are the same, tubing is the same,  therefore something in the levers must create a greater or more responsive pressure to move the pistons.)


When I find the time, I think I will map out all of the variations of the Buckalos/IIIPro 4-piston caliper and associated levers.  There appears to be a lot of mix and matching going on between different levers and basically slight variations in their calipers.


https://www.aliexpress.us/item/3256809632024344.html

jonathanf2

I was thinking of getting the 4 piston ZRace XG4 calipers, but it seems more work to maintain them.

The 2 piston Zrace XG pistons and seals can be easily upgraded to ceramic and serviced. I'm better off just running bigger disc rotors for more stopping force.

Tijoe

Since my last posting, instead of out riding on this beautiful Saturday, I compiled all of the Bucklos IIIPro brake variations I could find.   Attached are 2 images that show the list of models and brands, and a picture showing all of the different levers types.

My top 3 to look at are the; R2X4, R3X4 and the Frog Wake,   These pique my interests the most for eventual replacement of the IIIPro levers.
« Last Edit: September 20, 2025, 12:26:11 PM by Tijoe »


Tijoe

I guess i found another version of this brake.
Ryet Nexus
https://de.aliexpress.com/item/1005009200785644.html
They say 4x16mm Stainless Steel + Ceramic Piston? There is a lot of information in the description.
Good find.   I added them to my list.   Continuing down the the Ryet Rabbit hole, I searched under "Ryet Brakes" and they have another variation/copy of the R2X4 levers that they call the M4s.

https://www.aliexpress.us/item/3256809591481559.html

One would think that with all these variations of the same brake product line that these would be the best brakes out there considering al the rebranding going on on their basic designs.

Ryet is associated with Lexon, and Sroad, so I presume Lexon wants their own line of brakes to sell with their wheels and frames. 

Skepsist

Kinda interesting to have more color options tough the ryet version seems to be alot more expensive than the R2X4.

I guess if you need alot of power the radial levers of the R2X4 are the best choice. I would not trust them with my life but i'm stupid enough to try anyways. I'm not really heavy but i ride very bad so i'll report back when anything weird happens!
Enduro+Trials Rider

Fat Larry

So i got to use the R2X4 brakes today. Using the included finned brake pads which are probably semi-metallic. After a short brake-in-period they developed massiv power.
Usually i run 203mm Rotors but i dont think i need them with these brakes as they are simply very powerful so i'll stick to the 180mm that where included. The best comparison would probably be Magura MT5. Both in power and modulation.
Tough the IIIPro levers feel better and don't have as much resistance. The lever is very smooth but i had no issues with and without gloves. The IIIPro E4 levers are not even close i terms of comfort.
I will be using them until they fail, take them to some bikeparks check for thermal issues with a thermal camera. Not very scientific but i cooked some magura brakes before which was fun.

L-Twoo TX shifting was a bad choice tough but i'll write something about that in another post once i find out why its sucks so much.

Any leaks from the new barb?

Skepsist

Working very well. To be honest, I did not expect that since i'm spoiled by Hope Tech 4 V4's.
Would I trust them with working in the Alps? No not really. Alot of Brakes have failed that test. Magura MT7 overheated. Shimano 4-Piston XT Overheated and lost pressure. Magura MT5 burned the disc. Got a thermal image of 230°c on the disc.

But for my bike i take to the local trails almost daily they are very nice. They feel nice, modulate well and the stopping power is more than enough.
I will definetly post an update here if i find any problems.
A friend of mine is probably going to buy them aswell.
Enduro+Trials Rider

Tijoe

Well...

Yesterday, I finished up my 2.5 day bike-camping trip up in BC Canada.  About 15K up/down in 130 miles on my 53#/24kg loaded rig.
Guess what?
15 miles from the finish, my rear IIIPro brake failed.  (Not again!!!)  At least my front kept braking.  Luckily I didn't encounter any more downhill sand filled trail, but there were numerous 10+% singletrack downs and drops where it was a challenge only having a front brake. 

Not again!  This time, it appears to be a leak out of the hose connection or the line failed.    I will investigate soon.
This is less than 200 miles of riding since my last problem.
Note: I am attempting to use the IIIPro brakes on severe descents, where the brakes have to repeatedly stop over 250 pounds of mass. These suckers really should do the job...  OR NOT!



danielG169

L-Twoo TX shifting was a bad choice tough but i'll write something about that in another post once i find out why its sucks so much.

Not to go off topic but I put LTWOO T9 on my bike and am extremely happy with it. It feels even better than my Shimano GRX 810 on my gravel bike, although it is a bit difficult to compare drop bar groupsets to mtb groupsets.

Tijoe

I worked on the IIIpro this morning.  I appears that a leak developed around the nut/olive.   

- When I removed the nut to the rear caliper, the nut was goot-n-tight.
- I visually inspected the olive, and it didn't appear to have any compression marks on it at an odd angle, or any gouges in the sealing surfaces. All I could see were nice even polishing and a very slight groove compressed in concentric circles around the olive on each side.
- I installed the nut and tightened it down about as much as I dare, before causing damage to the threads.

- After drawing a copious amount of fluid through the hose out of the caliper bleed port, I initially had no pad motion until I spent 10 to 15 minutes working bubbles out of the bleed port in the lever assembly.

The rear brake is back to normal.   Not sure why the olive and nut area leaked. 
Perhaps prolonged heating of the caliper on many long descents?

Time will tell.   I'll be riding the bike tomorrow, on regular gravel roads without any steep higher-speed descents, and without any camping gear loaded onto the bike. The bike will be down to its 22lb base weight, +water.  (Versus my 53lb bike camping loaded weight.)