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i always got red instead of black, never seen those
Oh haha, my bad you're right. Red is correct not black. I was thinking of dominions
Can't say I've any time on Mavens, period (Wisco Pride n all) but this highlights why I never buy 1st gen anything. There's things you learn in development, then there's things you learn in the field after release. What's acceptable to the folx on payroll (lever feel/input here) may not be acceptable to the wider market. A smaller MC piston will provide a lighter touch when pushing bigger caliper pistons, but it necessitates longer throw due to fluid displacement in the system. There's no way of circumventing that because physics. So it looks like Magura has something right with the new Gustavs. Big caliper and MC pistons, high mech advantage at the lever to keep the subjective issue of 'feel' light while also maintaining a low internal pressure in the system (less chance of failure in fluid paths and seals). No matter of cam action will remedy that relationship between surface areas of the MC and caliper pistons and how the brake performs. The MC will always end up displacing the same amount of fluid to the caliper, and now the difference of force lies at the asym or sym of the caliper piston sizes (which this thread kinda proved out with the praises of the Bronze level Mavens). The cam just helps push more at X throw. Does this really matter? At this point I say no. Brakes have gotten so. freaking. good. Across the board. There's minutiae with pad compounds and rotor thicknesses, certainly. But at this point I think it's hard to find a bad disc brake at a price point above $200+ a side, and there are even more stunning examples below that. Sometimes WAY below (looking at you, non category Shimano 4 pots).
I absolutely love this thread of fahkery and mix/matching parts, but I can honestly say you don't need to drop a grand on a set of stoppers these days. We know that alloy MC pistons and phenolic or metal caliper ones do their jobs right for the long haul. We know that most brake lines are up to task. Production pads and rotors are mostly up to snuff for 98% of our (as a mtb community) needs, and there are solid aftermarket options on both fronts, both from 'known' and an 'unknown' brands. Slap a 2.3 rotor into any brake and feel how much its consistency improves when up to temp. Brembo entering the chat? Couldn't care less. They have manufacturing issues just like anyone else. I've seen it on that power sports side. It'll happen if they push into this market too. That's just manufacturing.
This isn't an attempt to stifle ingenuity or messing around with parts (spendy or not so). Sometimes we just need to take a more nuanced view as to what probs were trying to solve. I see way more human error issues when it comes to brakes than any amount of money that can be thrown at the prob to 'fix' it, and yeah some of those have been on the engineering side. Let's call em out when needed. That's why this thread is awesome. Keep messing around, but when someone drops a couple hundred on a set of stoppers and can't get em to stop 'right', we need to go back to basics.
funny how there never was a 2nd gen maxima brake. or a 2nd gen trinity brake
Intend currently sells the Trinity 2.0
and what did they change exactly?
really that hard to take 30s to google it ?
Okay, rotors
2.3MM solid or 1.8MM floating?
2.3 all the way not even a question 😅
I prefer solid, just for the ease of straightening. 2.3 is betterer than 1.8 also.
i know that, mine was a “1.5“ (2024 limited black friday model), now it has the 2.0 sleeves. guess what, technically it’s still the same brake with the same levers and the same caliper, therefore it behaves exactly as the 1.0.
The only thing that has me looking forward to Brembo mtb brakes is how easy it is to work on the Brembo brakes on my car. Their car brakes are super easy to work on as a home mechanic, hopefully their mtb brake will be the same way.
After some digging I found this thread. Lots of pertinent info:
Rotor OD vs. thickness
I have a goal. Reduce crustacean involvement in my MTB life. I eliminated the crab by choosing a VPP platform. Next is to eliminate the lobster claw syndrome I have after a long descent. My V10.8 came with Code Bronze brakes. Mediocre at best. Maybe with GR4s gripping 220/200mm 2.3mm thick rotors I can get to the bottom and still move most of my fingers.
This actually underscores the quality issues - massive variation, with hand QC’d samples going to the influencers.
A GR4 or even a TR with upsized rotors will do the job.
Gr4 with 220's will be a very good combo. Your fingers shall remain limbre indeed 😂
SRAM just downgraded all maven brakes to 18/18mm piston calipers. All new mavens are going to be a glorified maven base moving forward.
If you like the stopping power of mavens, too bad, they just got weaker. Super disappointing decision by SRAM.
might have been my skimming in reading but I missed the part of ALL going to 18s. I thought you'd be able to still obtain 18/19.5s. Dang that is a bummer if that is the case! I guess ya got to get the big meats if ya want em while you still can!
(still patiently(kinda only sorta) waiting for Brembos) They seem to be our next option for rivaling that top dog power and all the features with it.
I'm sure I read they were going to keep making the A1 generation calipers/brakes etc going forward for people who wanted that.
The changes to the B1 all seems like a response to issues people had with the A1 without admitting it. And the biggest complaint of all, "the lever is too hard to pull" confounds me to this day. Really?
I think the A1 line is preferrable in this chart, at least it's unique to other options an not similar like the B1?
My guess is that the B1 changes are probably to try and address the pump up and bite point issues they’ve had without admitting they’re a problem.
I’ve given up on mine. I have over $1000 in brakes in my garage that I’m not going to ride again. And I’m not really interested in throwing more money at them in the hope it fixes them.
100% serious:
What do you have and do you want to sell them for cheap since you have no intention of trying to use them?
I have some Code R brakes with bent levers that I'm tolerating but soon I'll need a bleed and a new set of rotors and a new set of pads. I'm either going to need to take them to my local shop for the bleed or buy the tools/fluids to bleed them myself. All that combined...and it's almost smarter to just grab a set of new brakes that will then use the new tools and fluids going forward for the next [hopefully a large number] years rather than maintaining and nursing along some not-that-great-and-has-already-taken-a-beating brakes.
They increased power at the lever which led to needing to downsize the pistons. Also like @yeahboiwahoo said they are keeping A1 (for now, at least…)
Thing that I alluded to in a prev post here. I wonder when the manufacturers are going to recognize that just maybe current hose and hose fitting inner diameters are too small to allow good, consistent fluid flow when the hydraulic ratios get beyond a certain point. There was kinduva similar point with full sus bikes back in the 90s-early aughts where it started to click that using a short stroke shock for long(er) travel applications was a bad idea. Having read Engel's initial A1 and subsequent B1 review of the Mavens on the Radavist, there was one thing that stuck with me in the last one, that after the brakes warmed up the wandering bite point/pump up issue decreased on the B1s. Yes, that can be a result of seal elasticity changes at the caliper due to heating up (I ride in winter in Wisco and have experienced similar), but I also wonder if a socal guy is getting it if there isn't something else also occurring, the cold oil unable to flow back to the MC due to the fire in a crowded theater scenario that is hydrolock, too much oil trying to get through the same port at the same time made worse by viscosity change due to colder temps. Downsizing one set of the pistons decreases the amount of fluid trying to return so may not create the same restriction or at least alleviate it some.
With that, it'd be rad to see an actual report on the different brake mineral oils' viscosities and tests showing flow rate changes for a wide variety of temps. Maybe that info is out there already and I am just ignorant. If so I trust someone here would gladly enlighten me.
Speaking to this point: "Downsizing one set of the pistons decreases the amount of fluid trying to return so may not create the same restriction or at least alleviate it some. "
I would have to think it has more to do with smaller seals creating less friction. The amount of oil moving back and forth is dictated by the master cylinder, not the size of the caliper pistons (the smaller the pistons, the more distance they move for the same amount of lever travel). Also, if a big piston gets stuck even a little bit, it would affect proportionally more of the fluid in the system, thus creating more of an inconsistency at the lever end for the same amount of piston stickiness. If that made any sense...
Four 18mm pistons moving .5mm displace about .5cc.
I see what you're saying, but as an example from a past career we had an issue with cavitation at the actuating piston (which would be the MC piston in a brake system) in a new system under rapid engagements, no problem under slow actuation. Sat in a review meeting where an engineer mapped out the inner diameters of the entire system. Only one dimension changed compared to previous generations which had no issue, 1 banjo bolt. It was slightly smaller through the throat and the cross drill. I latched on it and modified one of them, full cross drill rather than just to throat, and dilated the throat. Cavitation issue disappeared. Cavitation is a worse-case scenario, but cavitation can occur due to fluid being unable to respond to the release of an input.
Ideally, seal roll and slip should be the same between the 18 and 19.5mm pistons. Manufacturing of course is kosher with 99% equal action so it shouldn't cause an effect. Now if we look at rough displacements between 4x18mm and 2x18, 2x19.5, we see roughly a .05cc difference if we follow 63expert's math. for an orifice that's maybe 1.5-2mm max (think hose insert/barb), that's a significant change in volume trying to get through the door, especially if the oil is cold (molecules more packed together). As the fluid heats up and thins out, it becomes less of an issue, as shown by Engel's last review. At least that's how I'm perceiving it.
You're addressing two issues at the same time here. Absolutely the inner diameter of the hoses and ports matter in this case, if you create a choke point you can easily end up with inconsistent bite point etc due to the fluid not managing to move fast enough pull the caliper pistons back before they are activated again. However, the the point about the larger caliper pistons moving more oil back through the hose to the master lever is not correct. The amount of oil that moves up and down the hoses is solely dictated by the master cylinder. The pistons in the the caliper are not responsible for pushing the oil back when you let off the lever, the spring in the lever is. It pulls back exactly the same volume of oil as it pushed out when you pressed the lever. The resulting MOVEMENT of the pistons in the caliper will be different between caliper pistons of different diameter (which is how hydraulic leverage is created to begin with), but the AMOUNT of fluid flowing back and forth is the same, if the master cylinder is the same in both cases.
The Trinity is the second gen Maxima…
“The amount of oil that moves up and down the hoses is solely dictated by the master cylinder.”
The fluid is moved by the master cylinder, but the amount is defined by the caliper. It’s the volume required to take the pistons from retracted to contacting the rotor. You could calculate it with the piston diameters and the rotor clearance.
That’s why if you put a Magura caliper on a shimano lever you have increased lever throw over a shimano caliper. You have to move more fluid into the caliper for the pads to move from the retracted position to the contact point.
Cavitation occurs when a pressure drop causes the local pressure to fall below the vapor pressure of the fluid. In the scenario you described, fluid was being aspirated by retracting a piston, which introduced a pressure drop due to flow restriction. At low actuation speeds, the flow rate was low enough that the vacuum generated could still draw the fluid through the system without issue. However, at higher actuation speeds, the pressure drop became large enough for the local pressure to fall below the fluid’s vapor pressure, releasing dissolved gases into the closed system and introducing bubbles.
I’m not sure what fluid you were using, but for reference, the vapor pressure of both DOT fluid and mineral oil used in our brake systems is very low—typically less than 1 mmHg. It’s fairly straightforward to estimate when cavitation might occur using basic fluid dynamics principles.
To illustrate this, we can use the Hagen–Poiseuille equation to estimate pressure drop through a tube. While it relies on several simplifying assumptions and isn’t perfect, it’s usually close enough for evaluation and is something I use frequently.
The equation can be arranged to solve for pressure drop as:
Q = (ΔP*π*r^4)/(8*μ*L)
where
• ΔP = pressure drop
• μ = dynamic viscosity
• L = tubing length
• r = tubing radius
• Q = volumetric flow rate
Using the pressure drop required for cavitation (~14.67 psi or 759 mmHg of vacuum), you can solve for Q, which comes out to roughly 2189 mL/min. For assumptions, I used an inner diameter of 0.082", tubing length of 35", and a dynamic viscosity of 1.44 cP (based on a density of 0.96 g/cm³ and a listed kinematic viscosity of 1.5 cSt).
A 10 mm master cylinder piston has a surface area of 0.785 cm². Using the volumetric flow rate (~300 cm³/min for ease of units) and the relationship V=Q/AV = Q/AV=Q/A, the piston’s linear velocity would need to be around 2789 cm/min, or about 46.5 cm/s, to generate a sufficient pressure drop to induce cavitation under the stated conditions.
I thought this was an interesting way to look at the problem. Cavitation in our brake systems often comes up in discussions, and while it sounds plausible in theory, once you work through the equations, the flow rates and piston velocities required—given the fluids we use—simply do not support the physics.
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