Teardown | First Impressions
Formula Cura 4 Brakes Ridden
La Bella Figura
Available in the choice of a black, silver, or gold finish, I think the Formula Cura 4 is the best-looking brake system on the market. Does that matter? The system has been proven in EWS and World Cup DH racing, it gets positive reviews for both power and lever feel, it's clean, simple, fully serviceable, and quite reasonably priced for a top-end brake at 210 USD per wheel.
At least part of what makes it so attractive is the simplicity of the system. There are no magic tricks, superfluous dials, giant knobs I'll never use once the brakes are set up, or fancy copyrighted marketing terms. There are simply four 18mm diameter pistons per caliper being driven straight into my brake rotors by a long and nicely rounded lever blade.
The very shapely Cura 4 master cylinder. For a cleaner setup, they sell clamps to work with I-Spec-B and MatchMaker shifters and dropper levers.
Four-piston caliper. Formula specs the same hardware at both ends of the line but for a cleaner look, they do have a 90° fitting that would look sweet on my Marin.
That lever blade and the entire master cylinder assembly is shared with Formula's less intense Cura 2 brake, which I've previously reviewed, which brings up potentially the most interesting point about the four-piston Cura system: they really don't feel like Formula brakes.
It's early days in the review process but in the same way that Amaro and Chianti can both get you tipsy, the two Italian stoppers deliver different experiences on the trail. The Cura 2 carries forward the very positive engagement that Formula has been known for from the B4, to The One, to the R0R and will deliver exactly what the Formula brake lover is expecting. Because the Cura 4 is using the same master cylinder to move a lot more surface area of piston it has a much more modulated power-band that's more reminiscent of a Magura MT7 or even an SRAM Code.
Just rolling around outside Jeff's shop on the Cura 4 it's clear this is one of the nicest engaging brakes I've used but so different from the Cura 2 that it bears a strong mention for any riders who are thinking it will feel like the Cura 2 on steroids. Despite the almost doppelganger appearance the four-piston is a different animal.
Testing brakes with an extra 45lbs sitting on my top tube on the Kids Ride Shotgun system.
Jeff taking a moment to appreciate the nice, deep, even feel at the levers. No pad contact adjustment or other trademarked twiddlers.
Formula sells both sintered and resin pad options for the Cura 4. I'm on the sintered option but I'm also curious to try the resin for those water-cooled winter rides where rotors stay cold and the pads have a lot less chance to heat up. I'll comment on both options for the full review.
I'm also on Formula's new rotor pattern which is supposed to cut down on noise both wet and dry.
From basic Shimano MT-396 brakes, to the TRP Quadiem, to Magura's MT Sport, I'm a fan of brakes with long lever blades delivering lots of leverage and I'm keen to spend the winter on the Formula Cura 4.
As a general rule, I prefer the action of brakes with long blades pushing straight on the master cylinder piston. Leverage baby.
The TRP Quadiem is a great example once the bite of a sintered, non-finned, Shimano 4-piston pad is added. Like the Curas they're fully serviceable as well.
Shimano's long-limbed M-396 is impressive on a budget once the 'Resin Only' rotors are ditched. I'd love to try the non-ServoWave, '2.5 finger' XT T8000 masters mated to Shimano 4-piston calipers.
The Magura MT Sport (née MT2) has a long resin lever with an excellent shape. I'd like to see more injection molded glass fiber levers as they're much cheaper than carbon but better in the cold than aluminum.
The Cura 2 shares a master cylinder assembly, including the lever blade, with the Cura 4 but the Cura 2 has a more sensitive, on/off, touch.
Teardown
The Cura 4 is not a nanny-state brake. For better or worse there are no special tools required to take apart the master cylinder assemblies or calipers. They don't even require a trip to the tool store to get some obscure security bit. That means a decent mechanic or savvy home tech can fully refresh the Cura 4 back to new with fresh seals, pivots, pistons, bladders, springs, an so on.
The mineral oil system comes in three colours - gold, black, or silver - and the master cylinder and fittings are all the same as the Cura 2 so technically a couple of calipers* are all that's needed for the Cura 2 owner to up their bite to WC DH lever.
*Nb. The lever feel changes enough that I'd recommend doing both calipers, not just the front.
Cura 4 master cylinder all laid out. Every part is readily replaceable as part of a service at a service center like Alba, a solid local shop, or at home!
Cura 2 master cylinder all laid out from our teardown. Same-same but for the colour and graphics.
There are pretty much two procedures for bleeding brakes these days. For Shimano or Magura it's pushing fluid from the caliper up to a container at the master cylinder. For SRAM, TRP, or Hayes it's a pair of syringes with one at each end. Formula brakes match the latter and the syringes in their bleed kit are the nicest I've used.
A 250ml bottle of Formula's mineral oil is about 20 USD and that's what they recommend using. There are plenty of folks online who are working on these brakes at home who are using Shimano mineral oil which can be bought in larger volumes. It's not something I can recommend and I'd expect the local shop will use the factory lubricant bu it's worth noting.
Nice tool for bleeding brakes.
Nice tool for removing brake lines.
Nice tool for trimming brake lines.
Nice tool for bleeding brakes at the other end.
Nice tool for... oh, hi Jeff. How'd you get in here?
Yeah, yeah. I'm not as funny as I think I am.
Jeff recommends always doing a full bleed when cutting the lines and that's what we've done here. For the brake we tore down to the bones we ended up bleeding it twice to get all the air out but with the two syringes, it was a quick and easy job. The Cura 4 bleed takes a bit more focus than the Cura 2 and that comes down to twice as much space for air to hide in the caliper.
The standard Formula pads are compatible with the R1, RX, RO, Mega, The One, ROR Oval, T1, C1, CR1, CR3, and of course the Cura 2.
Four equally sized 18mm pistons force the pads into the rotor. The calipers come apart with two hex bolts to easily replace all the seals.
Formula needed to introduce a new pad for the Cura 4. They come in metal or resin compounds and aftermarket options also exist.
The brakes easily set up drag free. I'm currently running 180mm rotors front and rear and power is good. I also appreciate the lack of adapters required. I'm running a long travel 29'er, and a bigger front rotor on my other bike, so it's always in my find to mount a 203mm for the front. The power band is of the harder you squeeze the harder they deliver variety and the Cura 4 is very easy to modulate. To reiterate, folks that love the very positive feel of two-piston Formula brakes like the Cura will have a bit of an adjustment switching over.
The quality and simplicity of Formula's Cura lineup is obvious. They look great, small parts are available to potentially extend their life indefinitely, and I hope that the performance of the Cura 4 delivers making 210 USD per a wheel a very fair price for the package. More words once I have the requisite hours on the brakes, and there's also more information at Formula.
Comments
yish...
4 years, 6 months ago
"I'm also on Formula's new rotor pattern which is supposed to cut down on noise both wet and dry."
But not even a glimpse of the rotor in any of the pictures? ;)
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Andrew Major
4 years, 6 months ago
Hey, have to save some meat for the final review right?! Hahahaha. No, total oversight on my part when I was snapping photos; appreciate the call out. Here's a fresh one from my ride this morning:
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Lma
4 years, 6 months ago
Is that a 183 post mount on the Mezzer? Looks spaced too much for the disc?
Side note, have you had any strange noises from the Cura 2 on either rotor? Mine have always made a bizarre resonance/warbling when braking at low speeds on both the old and new (quieter) rotor design. Slight blemish on otherwise awesome brakes!
Cheers
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Andrew Major
4 years, 6 months ago
I have full surface pad/rotor contact. I did also check after seeing the photo on my computer.
R0R and Cura 2 were both louder than the Cura 4 particularly the fronts at low speeds braking down really steep slopes. I’ve experienced similar with many brake and rotor combos particularly after rotors have been used for lots of steep/slow riding.
The Cura 4 is all but silent right now (pads/rotors) even with sustained brake dragging but I’ll withhold final comment until I have enough hours and abject conditions.
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Rob Gretchen
4 years, 6 months ago
Hey Andrew... I hope you have better luck than me with the Cura 4s... while they did have a ton of power I could not live with the lack of pad rollback (a Formula trait) and lack of bite point adjust on these. As well I could not get rid of a massive amount of shudder they introduced in both wet and dry conditions. I tried them with multiple sets of pads and different rotors but with poor results. Unfortunately I gave up on them and switched to Code RSCs... Maybe there was more I could do but out of the box they proved frustrating....
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Andrew Major
4 years, 6 months ago
Hi Rob,
What do you mean by ‘pad roll back?’ That’s not a term I’ve heard before.
These feel much different than any other Formula brake I’ve ridden. Where with the R0R or Cura 2 I run the lever blades very close to the bar and they have very limited lever throw I find the Cura 4 has a lot more progression (a lot longer throw from actuation to full stop).
Engagement front and rear is very consistent; I haven’t experienced any shudder but I’m on a new rotor design so it’s possible that has changed since you tested them?
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Rob Gretchen
4 years, 6 months ago
I thought rollback was a standard term? This is SRAM's definition : "When the brake is released, the piston seals relax and pull the pistons/pads away from the rotor. This is known as pad rollback." In any case I did find engagement to be consistent but way too early.. I generally like a quick engaging brake but these I could not get along with and I did perform multiple bleeds to make sure everything was good to go. I also had the new rotor design. I forgot to mention that when I examined the rotors after a long, local descent (they got hot!) that a bunch of micro "fissures" had developed in the rotor surface... I've never seen anything like that before... maybe I got a lemon?
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Andrew Major
4 years, 6 months ago
Thanks, obviously don’t read enough manuals?! (Ha!) I’d never seen/heard the term.
They don’t use any magic to space the pads back from the rotor but the roll back is similar to Magura, TRP, and Hayes so other than a bit more effort on the initial setup vs SRAM/Shimano I don’t see that being the cause of your experiences.
I’ve a message in to Formula to see if there was a running change (master cylinder?) between the brakes you road and these because the totally different experiences just don’t make sense. As noted, these engage the opposite of early/abruptly (and unlike any other Formula brakes I’ve used) which makes sense since they’re using the same master as the Cura 2 but moving a larger surface area.
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Rob Gretchen
4 years, 6 months ago
Yeah, something doesn't jive that's for sure. I should have persisted to finding a solution but I was losing valuable riding time... maybe heading into winter I can send them back to Alba for an autopsy...
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Luix
4 years, 6 months ago
The amount of free throw at the lever is a function of the master cylinder's area and the combined slave area of the caliper's pistons. When using the same MC assembly for the Cura 2 and 4 brakes, the free throw on the 4s must increase with respect to the 2s simply because you need to displace more fluid to move twice the pistons at the other end.
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Andrew Major
4 years, 6 months ago
Luix, we’re comparing Cura 4 to Cura 4 where a change to the caliper piston seals after the first run resulted in more free throw.
You’re correct, and hopefully I did an okay job of explaining it in the article, that the difference between the Cura 2 and Cura 4 is the same master is driving 4x 18mm pistons with the 4.
Andrew Major
4 years, 6 months ago
Hi Rob,
The difference in our experiences does indeed come down to a change but it's actually to the caliper seals after the first run of brakes to increase rollback / free stroke.
If you reach out to Alba/Formula they'll get you sorted out. I would love to hear what you think of the updated feel.
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Rob Gretchen
4 years, 6 months ago
Yeah Matt from Alba just reached out to me... thanks!
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Hookem34
4 years, 6 months ago
Interesting....I had this issue with my Cura 4's back in January and recently purchased a new set of Cura 4's and they have much better modulation. Is it the piston seals or caliper seals?
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Andrew Major
4 years, 6 months ago
It's the updated piston seals in the caliper. Cool to hear you noticed a big difference - thanks. I never used brakes from the first run so it's not something I can compare personally.
Kyle Doherty
4 years, 6 months ago
How well does the hose quick disconnect feature work?
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Andrew Major
4 years, 6 months ago
Hi Kyle,
The Cura 4 brakes actually don't ship with the quick disconnect feature (it is an aftermarket upgrade) but I highlighted it in my teardown, with Jeff, of the Cura 2's when I reviewed them - here's a link.
It worked really well for me and is an especially nice addition if you're trying to move brakes around on different internally routed frames with tight entry/exit ports since the line doesn't need to be cut every time.
It's just like the quick fittings on an air compressor or garden hose just with an additional spring that acts as a failsafe. Remove the spring with a pic and then the pull back on the caliper fitting to pop the line off. Now I will say I've had fittings leak in both those applications so while I had zero issues with the feature it is an added complexity in an otherwise perfectly simple system.
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SColeman
4 years, 6 months ago
While it's a nice feature, some frames are TOO tight for the fittings. It was physically impossible for it to make one of the bends in the chainstay on my Pivot Mach 5.5.
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Andrew Major
4 years, 6 months ago
Yeah, their 90* fitting actually makes sense on a lot of frames where things are tight - especially with internal routing on the rear triangle.
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SColeman
4 years, 6 months ago
Not sure a 90* fitting would have helped. The issue I had was that the internal routing in the chainstay takes a slight s-bend, and the front of the rigid metal section of the fitting was hitting the other end of the bend before the back end entered it, so it physically couldn't make the corner. I needed the fitting to be about 1/4" - 1/2" shorter. In the end, I just cut the line at the lever and did things the old-fashioned way.
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Andrew Major
4 years, 6 months ago
My fault for not being clear, the 90* fitting isn’t a quick connect it’s a standard fitting that mounts the line straight down for the caliper mount. Just makes fitting tight frames clean. The standard straight fitting maybe worked best with your frame though?
SColeman
4 years, 6 months ago
Yeah, the straight fitting was fine - it just wouldn't fit through the frame's internal routing spaces. The angle coming off of the caliper wasn't the issue.
Velocipedestrian
4 years, 6 months ago
While I like the idea of a mineral oil, fully serviceable brake, I have to disagree on the looks. The formula aesthetic doesn't do anything good for me.
Can we get some more comparison with the TRP four pistons? I'm currently on saints, but the wandering bite point is starting to bother me...
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Andrew Major
4 years, 6 months ago
Strokes for folks right? The G-Spec Quadiem is a differently awesome looking brake.
The number one complaint you'll see/hear about the TRP Quadiem is the lack of initial bite. I've even met two riders who sold-on their brakes after a few rides because it was such an issue. They both agreed there's lots of control deep in the power-band (they worked great at speed) but for slower Shore trails where you tap the brakes to set up a move they didn't work for them.
My solution to this was to use (non-finned) Shimano 4-Piston sintered pads (I used to call them Saint/Zee pads but they fit a lot of brakes now) which makes for a totally different experience even sticking with the TRP rotors. I had a great review experience with the Quadiems (with Saint pads) and it's nice being able to use Shimano pads/fluid but at the same time have a non-ServoWave brake. The long lever blades work great to deliver easily controlled power.
The Quadiems have a lighter lever action than the Cura 4 - when I say that I'm not meaning it as necessarily a positive (I'm not saying it takes less effort or causes less fatigue) but rather the brakes feel less modulated themselves once I hit the bite point. If you've ever ridden the Hope E4 they feel very similar (but deliver significantly more power). I was thinking about this quite a bit today as I'm also currently testing a set of Hayes Dominions which thanks to their cartridge bearing lever pivot, leverage, and the design of their internals have the lightest of action of any brake I've ever used (by a good margin) with a significant bite point that HITS regardless of were the bite point adjust is set too. They deliver awesome power and are totally controllable it just takes a total reset of my brain to go back and forth between them and the Cura 4 and the TRP would be right in the middle.
Please let me know if that makes sense - it's something I'm trying to solidify to both talk about the Cura4 and the Dominion.
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Velocipedestrian
4 years, 6 months ago
Good feedback, thanks.
I'm of the Shimano school that says modulation happens in the finger, not the brake - hence being otherwise happy with saints on a trail bike.
So TRP could be high on the list when something non-serviceable happens to the saints.
I really like some of the ideas in the Dominion, but the piston being above the reservoir in the master cylinder combined with dot fluid make them a hard sell for me.
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Garrett Thibault
4 years, 6 months ago
I bought the TRPs. They’ll probably end up on my hard tail.
Not enough power for my liking in the bike park, and I’m 180lbs. I even tried upping the rotor size to old Magura’s that were 210 (?) front and 203 rear.
Someone in the lift line at whistler asked me about them, and I replied that I was actually wanting to ask the guy beside me who also happened to have them what he thought because I was finding they didn’t have enough power. Guy beside me in the lift line was offended and told me yeah he has to brake with two fingers sometimes, but they have ample power. Dude that asked me responded that yeah, his kid had them and found they didn’t have enough power either.
I bought a set of the Magura MT5s for a good price from Germany. They’re feeling more powerful than the TRPs so far on the enduro bike, and they were cheaper. They’re also mineral oil and have the plastic lever for cold days. I’ll have them on the downhill bike next season, but it was too big of a pain to do the internal cable routing at the end of the season, especially considering I’d like to have them back on the enduro bike this winter.
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Garrett Thibault
4 years, 6 months ago
I bought the TRPs. They’ll probably end up on my hard tail.
Not enough power for my liking in the bike park, and I’m 180lbs. I even tried upping the rotor size to old Magura’s that were 210 (?) front and 203 rear.
Someone in the lift line at whistler asked me about them, and I replied that I was actually wanting to ask the guy beside me who also happened to have them what he thought because I was finding they didn’t have enough power. Guy beside me in the lift line was offended and told me yeah he has to brake with two fingers sometimes, but they have ample power. Dude that asked me responded that yeah, his kid had them and found they didn’t have enough power either.
I bought a set of the Magura MT5s for a good price from Germany. They’re feeling more powerful than the TRPs so far on the enduro bike, and they were cheaper. They’re also mineral oil and have the plastic lever for cold days. I’ll have them on the downhill bike next season, but it was too big of a pain to do the internal cable routing at the end of the season, especially considering I’d like to have them back on the enduro bike this winter.
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Velocipedestrian
4 years, 6 months ago
Did you try Shimano pads?
I agree, it's hard to go back in power once you've had it.
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Garrett Thibault
4 years, 6 months ago
Yeah, I have Shimano pads front and back. I gave up on the front pretty quick though. I’m still running the TRP rear, but I put an old code on the front for the majority of this season.
Andrew Major
4 years, 6 months ago
Interesting Garrett. Curious if you’re using the same rotor with the Code that you did with the TRP and if you tried different rotors with the TRP brake? I’ve read a few comments from people who have thought the TRP rotors didn’t bite as well as others but it’s hard to compare apples:apples.
I did upsize my front rotor with the TRP (203mm where I usually run 180mm front and rear).
Garrett Thibault
4 years, 6 months ago
I ran avid/code rotors, developed a leak in the rear code lever, pulled the TRPs off my enduro bike and put them on my DH bike. i didn’t like them so I swapped the TRP pads to Shimano. Then swapped both rotors to bigger Magura’s. then gave up and put the front code back on and am dealing with the rear. The TRPs were on Shimano rotors on the enduro, but they didn’t see too many rides and had the stock pads. The MT5s on the same Shimano rotors feel pretty good already even with the stock pads.
Andrew Major
4 years, 6 months ago
Thanks! Yeah I went back to my Magura’s once the TRP test was done - my main reason was my M/L hands, it was a balance between getting the blades where I wanted them relative to the bar VS where there’s max leverage for braking VS the lever not having enough of a hook at the end at full compression relative to where I ran them.
Velocipedestrian
4 years, 6 months ago
Hmm, maybe not then. I fit a medium Troy Lee glove, and already use 203f 180r rotors with the saints.
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danimaniac
4 years, 3 months ago
Hey Andrew,
when will you follow up this and the Dominion's teardown with a longer review piece and maybe a sweet nice comparison on braking power and such?
I'm trying to decide between these two and the MT7 but I just cannot :D
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Andrew Major
4 years, 3 months ago
Totally Dan, I hope both will be live in early February.
Cam and I are both working on the Dominion review which adds a layer.
For Cura 4 I added an element by buying a pair of calipers to mate with the used & abused Cura 2 masters from my previous review. Also testing a new organic pad vs tried-and-true sintered.
Thanks for reading!
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Bavaria 2.0
4 years, 6 months ago
I had the same lack of roll back problems with a pair of Cura 4's last year. No one would reply to my help inquiries through the Formula USA web contact. I finally connected with someone at Formula Italy via the Formula account on Pink Bike. After a couple of back and forth's for help through Pink Bike, Formula stopped responding.
Pretty poor performance from the brakes and even poorer performance from Formula customer service. This is the same combination of problems Formula has been having with their brakes for years.
Reading through the conversations above, it sounds like there may have been some seal issues with the early Cura 4's? I really would have appreciated it if Formula would have stood behind their brakes and helped me out.
YOU LEFT ME HANGING WITH BUNK BRAKES, FORMULA. Weak. I'm now on Saint's.
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Andrew Major
4 years, 6 months ago
Sorry to hear you had such a poor experience - hopefully the LBS or online shop you bought the brakes through got you looked after.
I obviously don't know all the details of your experience, but I do know that between testing the R0R and the Cura2 that Formula changed agency in the USA and some of my communications were lost as well.
I can't speak for anywhere outside of Canada but I've heard many positive customer service stories about Alba in Whistler and I've had nothing but great experiences getting information and buying small parts.
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SkullsRoad
3 years, 5 months ago
Anyone know how to get the lever off the pushrod? Bent a lever in a crash today.
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