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Has anyone modified their non-Hayes calipers to tap a grub screw into the mounts, as in Hayes's "crosshair" caliper alignment feature, and lived to talk about it?
I'm curious, although I don't have a drill press or mill or any way to align it properly, so I'm not about to try it myself.
Closest I've gotten is filing down Shimano and Magura Calipers so hope rotor rivets clear them. I bet you could, probably would recommend using a drill press and vise to make sure it's lined up well, but honestly, those screws haven't done much for me, they tend to move around under vibration
In reality, go to first page of this thread, Code R and RSC difference is virtually none in terms of power output with the same lever force, rotor, pads of course.
and a 20mm gain in rotor size it's actually more power gained then R to RSC, they might feel better but it's not much for the price.
I've never used them myself but from what I've heard from other people the crosshair alignment on the Hayes sounds great on paper, but not quite so useful in practise.
I don't believe that test in the slightest, I went back to back and there is absolutely a huge difference in feel and grunt for the same input force. I didn't touch the pads/rotors anything else. There was a fresh bleed, check, swap lever, test again and it was night and day.
I see you've questioned some of the results yourself?
It's possible to use them wrong. If you follow the procedure that makes the most of them they're great, quite an improvement over the standard process. If you don't, and take the same kind of approach you would with a brake that doesn't have them then they kinda just get in the way.
- Back out crosshair screws
- Push on caliper to move it inboard so outer pad is fully in contact with rotor
- Tighten down caliper bolts until you just can't move the caliper by hand (not until play is gone, i mean until you are unable to adjust it by hand at all)
- Tighten each crosshair screw until it hits the caliper bolt and starts to move the caliper outboard
- Edge the caliper out slowly, alternating the screws. You get the feel for it. Once you do, it's easy to do in three adjustments: one crosshair screw, then the other, then back to the first for the final adjustment
- Nip up rear caliper bolt then front caliper bolt.
If you try to use them with the bolts loose, they suck. Any movement at all in the caliper they suck. Don't try to loosen one bolt and then adjust it back the other way by loosening the crosshair screw while pushing on it with your thumb then retightening once it's in the right spot, it sucks. If you adjust while there's no tension on the bolt, everything hasn't squished down nicely yet so when you do tighten it down it moves the caliper slightly. If you do go too far outboard with your adjustment then back the screw out, push the caliper back, tighten the caliper back down, and then start again. But it's so easy to not overshoot the adjustment that you'll never do it once you're used to it.
I'd second a lot of this.
If had Code R's on anything short of a full-blown enduro bike, I'd trying to find a deal on two RSC levers with the old-school hose angle that works better with mechanical shifting (what I run) and then use good 2mm thick rotors with MTX red pads and focus on getting a really good bleed and then bedding in the pads and rotors properly.
Then I'd call it a day and start worrying about and spending money on other aspects of a bike that (really don't mean to be a dick here) came with Code R's. I bet there are number of non-brake upgrades that'd make more a difference then Code RSC's as described above vs something slightly fancier.
I've got Mavens on my enduro bike, but I have Code's on my midpowered, "lightweight "160/150 ebike and for most of the riding I do on the ebike the Codes are fine. Running 220/200 rotors front/rear. Maven's are a LOT of break.
That basically how I do it with "regular" calipers, but with the addition of a repeatable fine adjustment. Seems like there's no downside, cheers.
Might be worth spending some time getting the pistons nice and even and moving freely before wasting any money, IMO it makes a big difference to the spongy feeling and overall power.
Bit of an older video but if you haven’t seen it ‘How to make your sram brakes not suck’ on YouTube has good tips and none of the fluff.
Agreed, there are enduro mag tests where Code R is on par with Guide RSC and Code RSC way above that - the swing link adds as much as larger pistons do (Guide vs. Code).
Also, 'no added power' as per numbers, yet the stopping time is lower by 20 %. How is that possible other than with more overall braking power?
Makes sense. On Codes (or in general), I undo one bolt, tighten it back just a bit, then do the same on the other, then, when adjusting, untighten one bolt and move the caliper left-to-right to see daylight between pads and rotor, tighten back the bolt a bit and repeat the process on the other side. So I have one bolt fixing the caliper in place and providing a pivot point, but only ebough to be able to move the caliper by hand on the other side, where the bolt is loose.
How was the test set up? I assume there were control tires and a control surface stopping from a specific speed?
https://enduro-mtb.com/en/best-mtb-disc-brake-can-buy/
That is the link of the group test most people are mentioning. The decelaration test were done at Sinter testing lab so no issue of control surface or tires, weather conditions and tire pressures. Brake pads tested were both the OEM one and also tested with Sinter green organic pads. Rest was either measured or controlled.
Full test procedure from Enduro and Sinter:
We carried out extensive test sessions at the Sinter lab in Slovenia. Here, Sinter not only manufacture their own brake pads, but also have a big test-lab, which they were kind enough to share with us for several days. Following their recommended break-in procedure, we put the brakes through their paces on the test bench using the original pads.
This procedure was followed by 20 sequences of two test procedures each: the first test simulated deceleration from 30 km/h to a standstill, while the second test simulated decelerating from 30 to 15 km/h. This is a classic scenario that occurs when braking before a corner. The brakes were given 10 seconds to recover between each of the 20 sequences. In addition, we ventilated the brakes constantly to simulate natural airflow. The results are the average of the 20 tests performed.
To generate the braking force, we always applied 40 N to the brake lever, which corresponds to a tractive force of 4 kg. After testing the brakes with the original pads, we carried out a second round of tests with Sinter’s in-house “Race” pads to find out how much tuning potential is in each brake. The Sinter pads – which are organic, by the way – improved deceleration on all models, but to very different degrees.
Thanks for linking that. The data definitely seems a bit weird to me, and it's not clear on everything, though the methodology in the lab seems pretty good. I wish they disclosed exactly what Sram Rotor they used, I can see that it's an HS2 for the Maven, but it isn't clear for the Codes. We're those rotors fresh for each set of pads and bedded in the same way before the test? Where are they measuring the pressure, somewhere along the hose? Another thing I'm not sure what they are meaning by brake torque. Is that the average of the maximum torque experienced during each test or is it something else? I find it interesting that the Code Ultimate took significantly longer in the 30 - 0 tests, but the Bronzes took longer in the 30-15, with a significant drop in torque for the ultimates for the 30-0 test. Given the other controls, I wonder what caused that inconsistency. They should put out all the raw data from each test, I would love to go over it.
Yeah, there's too many red flags in the data to take it as gospel. I'm not the sort of person who demands a full engineering report to back up every scrap of data before i believe anything, but in this case it just doesn't seem like they had a reliable testing methodology.
I'm baffled by the apparently random selection of OEM pad compounds
Ehm, brakes comes with random pad choice from the factory, who's fault is that? They were testing STOCK brakes, if manufacturer opts to undersell their brake by cheaping out on pads, it's their reliability. Better pads and rotors make any brake better, after all those are the actual braking surfaces, of course they make a big difference.
Pads and rotors are both things easily changed by the end consumer.
For the lab data, they should have used either control pads and rotors from someone like Galfer, or used the best available from each OEM. If they wanted to use whatever OEM pads were fitted for subjective on-trail testing that would be fine but you don’t get meaningful lab data with a random spread of pads.
Another note that makes me question their testing too: their setup photos for the Maven on the lab test make it look like they may not be applying force to the correct point on the lever. This wouldn’t matter for testing different pads in the same brake but would invalidate comparisons between brakes.
I do testing for a living. This shit drives me nuts.
Edit: what I’d also really have liked to see is a graph of brake torque vs lever force and another graph of brake torque vs lever displacement. I think it would give some really interesting insight into why certain brakes feel the way they do.
What part on the bike is not easily changed? (Forget headtube routing for a second). While we all would appreciate more detailed test and deeper analysis of braking performance, it's hardly something any online magazine is going to do for us, same with damping rates of different suspension products, wear rates of cassettes etc. Plus, I think more often than not we empirically know very well that is you want more mechanical advantage in a brake you have to either compromise lever feel or compromise pad rollback. That is unless you go for variable cam mechanism in a lever (even though that messes up the lever feel as well just in a different way).
I've been a bit curious about how most people center their calipers. I initially would center based on the gaps in the pads, but when I worked at a shop, I learned to center the rotor between the caliper gaps and ignore the pads initially. Then if the pads made uneven contact (assuming the pistons had been cleaned and lubed), you could work the brake lever and use a small flat head to massage fluid from one piston to another to get them dialed in. If I've helped someone trail side with brake rub, I just center to the caliper and it seems the fluid in the pistons balance out after some braking
Not sure if it's an odd way to do it but I've found its been simple and effective compared to other methods I've tried.
super cool POV with Brake Ace data laid over top - Dante Silva and Tyler Ervin on Telonics - figured it goes best in this thread.
Compromise lever feel in what way? I've been running the Hayes Dominions for a few years now and they have felt great and really delivered on the power. They don't feel compromised in any way to me. The mechanical advantage comes from how easy it is to increase the pressure in the system. Think of Bernoullis equation. Removing the energy we won't really be considering in a brake system like this, kinetic and potential, (p1 +1/2pv1^2 + pgh1 = p2 +1/2pv2^2 +pgh2) We are left with P1=P2. Pressure at one end is equal to the pressure at the other end. Pressure is equal to force/area, so we can increase force at the caliper end by increasing the area the pressure is applied to, and we can increase force at the lever end by increasing the length of the input arm relative to the output arm. You can use cams in the lever arm to change the mechanical advantage through the stroke, and the feel of the lever.
I know I'm being overly simple on this, but I'm still not sure what exactly would be compromising the brake feel of you go higher power, especially since feel is a personal preference.
Long free stroke is part of overall brake feel for me?Dominions are pretty extreme in this aspect. From the top of my head I don't know about any other brake with that much free stroke, even brakes that are more powerful (on paper at least) like t4v4, both of them feel nicely linear though. On the other hand you have servo wave shimanos with very wooden feeling initiation that gets ok ish once you get to the pad contact point, and they get there quicker while also running a lot more pad rollback so disc clearance is good.
How many people actually change pads and rotors? Testing brakes as they come stock is 100 % the right way to do it.
I was more surprised that the caliper was bolted to the carrier from the bottom (no friction taking up the load) and maybe that the force applied to lever was an overhang, not sure if us grabbing the bars and the lever makes any changes or not...
As for different braking forces, as long as the flex of the system is at least close to linear (should be), the torque response will also be linear. Where changes would have been seen is where flexibility of the hose and caliper would make a difference in lever throw (against the master, not the handlebar) and would disproportionately increase the braking torque at higher braking forces because of the lever to piston cam improving things.
The people who are interested in these test results are the ones changing their pads and rotors! (Edit: although it's pad compounds I'm concerned about, per the original comment)
The test wasn't even internally consistent. In some cases they have different OEM compounds within the same brand, meaning all that effort was a waste.
Although given this is page 51, I doubt I'm adding anything new here.
Of course a long post typed on my phone gets eaten by the system...
Testing brakes as they came is the only logical way of doing it. If they come with different pads within the manufacturer, that's how it is. If they were to test with a spec rotor and pad, which one? Why the one you say and not some other one? Should they test all of them available on the market? Even the aliexpress ones? See the issue? Also, said test was not aimed at this thread.
Brakes are, as anything these days, being sold as a system. They should be evaluated as such. Aftermarket pads and rotors should be tested separately as an upgrade option.
The only case where a spec rotor and pad would make sense is if brakes were sold without either in the kit. For rotors this is the case, but then you should evaluate them with rotors from the list of compatible ones. Which they did - OEM ones. Otherwise, where do we draw the line? Should frames be tested using spec components and bearings to filter out the differences? Put Cascade links on all of them to I don't know, level out the kinematics and only test flex and other ride characteristics?
Dominions are extreme with free-stroke?
I just went and measured mine. All four are running at 15mm free stroke before a pretty solid/obvious bite point, measured just before the hook on the lever. Is that a lot? It's less than my twin pot shimanos (which are theoretically less than the 4 pot shimanos I think, due to less piston area?)
One pair is 2 years old and has not been bled since new, other pair is probably 5 rides old, and i don't do any tricksy stuff like advancing the pistons. Just set and forget.
Its a well known characteristic of the brake as documented in quite few threads on multiple forums. I have tried 3 sets, all of them have longer throw than any other top competitors. Can they be fettled with to improve this aspect? It looks that way as per page 12 in this very thread. However apples to apples (or Stock to stock), they have longer free stroke than any other brake I have tried, code rsc with bite point adjusted all the way in is comparable I guess, haven't measured it so not sure, adjusted all the way out it's noticeably shorter though. They are good brakes, no one is doubting that so no need to be butthurt. Just not a perfect one.
I'm not butthurt, this is just the third pair that has been the same for me and less than my shimanos out of the box. I measured because I'm curious to compare it to others!
edit: reading page 12, he managed to reduce the free stroke by 12mm. Given that I have barely more than that to start with, it sounds like an assembly issue rather than a characteristic of the brake.
The beauty of testing with a spec rotor and pad is that it doesn’t matter which one you use as long as they’re all the same. Even if you use a bad pad, it’s equally bad for all of them.
If a Maven with a shitty pad from aliexpress makes 30% more power than a Code with the same shitty pad from aliexpress. Then you know definitively that the Maven makes 30% more power than the Code.
If you test a T4V4 with a Hope Green pad against a Maven with a sram “organic” pad and the T4V4 has more power on the dyno, does it actually have more power? You don’t know because you have a really good pad in the Hope and a mediocre one in the Maven. Is Hope green even the OEM pad? Well yes and no. They come with green in the box but they also come with two other lower performance option in the box too.
It’s like testing sports cars but some of them are on all season tires and others are on r-compound tires.
Edit: to compare it to your bike test analogy, it would be like putting all the bikes in a group test on the same tires. Something that the media outlets frequently do for group tests.
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