I share your concerns, but in my own experience, the anorexic mounts would suffer a lot more from crashing rather than from hard braking.
Frankenbrakes and brake improvement discussion
- Thread starter Udi
- Start date
that's actually a pretty nice looking brake. however not being able to back load the brake pads is pretty much a non-starter for me.I've been following these guys on insta for a little bit:
Looks interesting and one of the first non frame applications of 3d printed metal components...
Pistons are 15/16mm unlike the hefty 18mm Cura4's I'm currently on but looks like they could offer some benefits over a traditional manufactured caliper.
Some of the drawbacks are surface will be rough and potentially gather grime, not sure on implications of this internally for fluid flow - however being 3D printed it could be designed for super easy bleeds.
Discuss...
is this even the internet?
I think what I was attributing to pad rocking was actually rotor deformation getting really hot and rubbing since formulas have such a narrow pad/rotor clearance.
In my case I was getting rotors that would rub after steep sustained braking. Then it would stop after a few seconds of cooling off.
I was told many moons ago about the pad material transfer, and was also told not to mix rotors and pads. Organic pads go with their own rotor, sintered their own. Running one type of pad on a rotor broken in with the other type will compromise ultimate performance. I have never bothered with this, just a sanding and alcohol wipe, although that is not supposed to fully ameliorate the problem.
There have been times I have run one organic and one sintered pad at the same time - but that is a whole other discussion.
There have been times I have run one organic and one sintered pad at the same time - but that is a whole other discussion.
I have been trying to research pad/rotor material transfer and discussing it with a friend who's a material science person.
Any material transfer from pad to rotor is going to be a very thin film and it's going to tend to be transient, perhaps less transient on stainless rotors.
There are many materials used in pads, and I'm guessing that virtually all are varied and proprietary in their makeup; resin's an incredibly vague term.
I'm going to guess that the odds of the film from pad type A on a rotor is not going to be sufficient to contaminate pad type B meaningfully and that if one takes the time to bed in new pads as recommended, it doesn't matter what type was installed before.
I don't think material back-transfer to contaminate the pads is the issue, but the ultimate friction is developed between the pad and the microscopic pad material embedded in the rotor. If the pad and the embedded material are different, max friction is not generated.
Same as trying to break in pads on a rotor broken with the other type. There will be minimal material transfer as the rotor is already loaded, and we are back to the dissimilar friction materials.
I usually don't run sintered pads, so on the odd occasion I do, like I said, I just give em a good sanding and alcohol wipe and then just get on with it.
@Udi - can you throw a little light this way? Any idea if any of this is correct or just handed down old-type bunkum?
Same as trying to break in pads on a rotor broken with the other type. There will be minimal material transfer as the rotor is already loaded, and we are back to the dissimilar friction materials.
I usually don't run sintered pads, so on the odd occasion I do, like I said, I just give em a good sanding and alcohol wipe and then just get on with it.
@Udi - can you throw a little light this way? Any idea if any of this is correct or just handed down old-type bunkum?
Shimano xt brakes still have the inconsistent bite point problem according to MBR.
https://www.mbr.co.uk/reviews/groupset/shimano-xt-m8100-groupset
https://www.mbr.co.uk/reviews/groupset/shimano-xt-m8100-groupset
Isn't this crazy.
Serious question... how much would it cost the consumer to have an actual working set of XT level brakes? I can get a set of useless ones right now for $300 AUD. Surely a company the size of Shimano could get something actually decent for $600, which is still only half of what a set of Trick Stuffs cost. There's a market there.
Shimano, are you reading this??
I'm more surprised they don't get a huge sueball from a consummer association. I guess the Shimano love runs too thick in the MTB bloodstream. Seriously, try to get a car or moto brake this defective to the market and you're guaranteed to have your grandchildren paying for your court fees.
Shimano brakes used to work and were affordable as well.
There's also a tonne of people on here who seem to want to convince themselves that Schwalbes are bad, yet they're the #1 choice for a bunch of people I highly respect in different corners of the world riding very different terrain - people who have cycled through every option under the sun to make their call. But who wants tires that grip? Then you'd need brakes that stop!
You can sit around arguing with these people, or you can keep riding bikes and find other hobbies. For example today I spent some of my free time re-watching "Who is America", a nice reminder that this scenario isn't scary - rather just common reality (particularly in NA). What's scary is that we're wasting our time reading about and responding to it.
I agree with @johnbryanpeters and I'd trust his sources more than mine (me).
I've noticed the recent discussion on this but I'd say the effects (if any) are negligible in MTB. What is a far greater consideration is that old rotors tend to develop a concave profile across the braking track, and this results in the new pad seeing localised heating until a point where the pad profile reaches sufficient convex to match the concave track.
Not as big an issue with semi-sintered/organic pads, but with full sintered pads which are prone to heat-related friction reduction AND have a much slower wear rate, you can very easily glaze / permanently reduce their maximum friction capacity by running them on an old rotor. This can still happen with other pads, it's just more difficult to generalise.
This is precisely why pads (particularly sintered ones) will generate noticeably higher peak friction if brand new pads are used with brand new rotors, than when brand new pads are used with old rotors. It's far less of a concern with Shimano heatsink sintered pads for obvious reasons, and also in my own experience.
You might want to specify which Schwalbe tires you are talking about. I don't know anyone that likes Nobby Nics, Hans Dampf and their trail/XC tires. Yes, they roll fast, but they flat easy, rip knobs off and generally are "meh" tires.
Magic Marry is a good tire IMO, but at the price they sell them for I would expect that they do not have ripped out side knobs after a handful of rides. Disclaimer: I did not test all their new compounds and experience is solely from 26".
What further puzzles me is that weighing a bunch of Schwalbe tires (same model/dimensions) out reveals significant fluctuations, indicating that they do not have good control over their production process.
If that is the case then they all suck.
Off of the top of my head....
I have ripped knobs off of
Maxxis
Kenda
Schwalbe
Michelin
Continental
Panaracer
Cheng-Shin (20" BMX back in the day)
They must just be different versions of cheese, cause I sure ain't fast and schralpy.
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"My _____ (insert Shimano brake model here) have been flawless! You probably are not bleeding them properly"
Honestly, I know the DOT Formulas are outdated, but I just fixed a leaky lever in ~15 minutes including the ulterior necessary cleaning. A 10 cent o-ring and some patience was all I needed to have it working as intended. The simplicity and effectiveness of the design is outstanding.
I'd wish they would have updated their radial piston line instead of coming out with the Curas. My friend who is a pretty competent bike mechanic couldn't get the spongy feeling out of a set of Cura 4s after two days of bleeding them.
I'd wish they would have updated their radial piston line instead of coming out with the Curas. My friend who is a pretty competent bike mechanic couldn't get the spongy feeling out of a set of Cura 4s after two days of bleeding them.
I hereby claim that the TrailStar / super gravity Magic Mary sucks donkey balls. A few dozens miles in the front and the knobs are worn as fuck, and it never gripped well on wet rocks and roots either. 
My orange-stripe 60A Maxxis Mobster gripped really poorly too, all Maxxis tires suck.I hereby claim that the TrailStar / super gravity Magic Mary sucks donkey balls. A few dozens miles in the front and the knobs are worn as fuck, and it never gripped well on wet rocks and roots either.
Strong, currently-relevant logic.
In the realm of tires, Kenda and Schwalbe are standouts for poor design/QC. Schwalbe is ok in it's paradigm, but if you ride where there's a hint of sharp rocks you better know what you are doing. I like some of their XC race tires...but only as race tires on race day, not for all-around riding or in-between-races, etc. That's a way to have something bad happen during a race. On their lightest casing tires, you could hold them up to the sun and see the sun shining through. Kenda has come a long way, but the quality back in the day when they were trying to break into the scene as their own tire company was abysmal. I did buy a bunch of cheap kenda tires...and I did get a bunch of warped casings and knobs that ripped off on the first ride. Both of these companies have addressed the issues to a large extent IMO, but everything from them is suspect IMO.
Sure, but the ratio of bad to good tires is a little higher for Schwalbe for me. The only of their tires that I haven't ripped knobs off in a short time are the Tabletops. But one was 80 g and the other 120 g over the advertised weight of 590 g!!!
With Maxxis I had a bad tire here and there, Conti were all OK (small sample size though), ITS tires were generally OK but heavy, from other mfgs I have not enough sample size of more recent models to judge.
That's the point.
I see these exact responses to questions about their current product line, it's always from the same people.
You're the only one who has actually tried the latest and didn't get along with it, that's fair (although I reckon it's to do with your whackjob bike length - I still run the DHF you suggested over it, and there's no way it remotely compares IME) - everyone else is making commentary that is currently irrelevant. For reference, my fanboy tally is buckoW, toodles, Flo33, myself, and plenty of others not on RM who highly rate (specifically) the current purple-addix magic sg, having tried most else. I'm also a big fan of the dirty dan (again in softest compound) which I've ridden all over BC in the wet.
The parallel I was drawing is that many here (not you) love to comment on stuff they haven't tried, or extrapolate experience with a different product (see above from Jm, iRider - who primarily ride XC/trails + related casings / compounds) to the one someone is asking about. The place is also brimming with people who will buy a $500 product, repeatedly, while claiming the $1000 product (which they haven't tried) is "overpriced". That's why this thread is alive and healthy.
I still run the RORs on my trailbike and don't mind them, although I've mated to Hayes Prime calipers both ends for marginally more peak force and pad surface area (for wear life / glaze resistance). Also 203mm rotors F/R. One thing I rate about the Cura (4 specifically) is the larger pads, though I don't own them.
My rear caliper is overdue for a seal change, long throw as a result, but Hayes seal/piston kits are overpriced (more than both Hope and Formula) annoyingly, so I've been wondering what to do. Options include going back to the Formula caliper (hate the small pads), attaching a V4 caliper (expensive), or just rebuilding the Prime.
I don't ride this bike enough to justify much $, any suggestions? Maybe franken-calipers in DOT I've missed?
I think it came to like $40US posted which would be fine for a finely made component which I intended to keep forever, but the Hayes stuff is poorly made compared to TS / Formula / Hope, I bought the Primes dirt cheap so it's more a "principle" bridge I don't want to cross. I also can't find the seals alone.
The reason I ruled out SRAM (apart from being SRAM) is they traditionally use smaller total piston area - no problem when also using smaller master area to match, but I think they'd make for a weak brake with Formula levers. The RO has quite large total area, the Prime Pro a little more even. Correct me if I've missed a SRAM option which will work though, cheap from ebay is what I had in mind.
The other thing is, this bike sits around unridden a lot, and I've found SRAM/Avid gear tends to seize up / have weird effects if left around, Formula is better though recently my front brake was locked and I've had to let some fluid out. This is an area where aside from TS, Hope and even Shimano (apart from when the calipers leak) are both very good. I've wondered if having a traditional directional/upright reservoir has something to do with it, but with SRAM brakes I feel the caliper piston interface gets sticky too.
The reason I ruled out SRAM (apart from being SRAM) is they traditionally use smaller total piston area - no problem when also using smaller master area to match, but I think they'd make for a weak brake with Formula levers. The RO has quite large total area, the Prime Pro a little more even. Correct me if I've missed a SRAM option which will work though, cheap from ebay is what I had in mind.
The other thing is, this bike sits around unridden a lot, and I've found SRAM/Avid gear tends to seize up / have weird effects if left around, Formula is better though recently my front brake was locked and I've had to let some fluid out. This is an area where aside from TS, Hope and even Shimano (apart from when the calipers leak) are both very good. I've wondered if having a traditional directional/upright reservoir has something to do with it, but with SRAM brakes I feel the caliper piston interface gets sticky too.
Thanks for the thorough answer. I didn't take the master/slave piston area into account. Just thought of any other DOT calipers in the field.
There are a couple of Chinese unknown brands out there with 4-pot DOT calipers, but without knowing their slave piston area it would be just a shot in the dark...
There are a couple of Chinese unknown brands out there with 4-pot DOT calipers, but without knowing their slave piston area it would be just a shot in the dark...
And this is exactly why I do not buy Schwalbe tires anymore. I was too often tricked by "tests" and recommendations from friends that made me believe they are great and everytime I ended up disappointed. So same reason you did not buy any of the newer generation Shimano brakes but moved on to other products.The place is also brimming with people who will buy a $500 product, repeatedly, while claiming the $1000 product (which they haven't tried) is "overpriced". That's why this thread is alive and healthy.
I get your point. I just thought he did a totally reasonable job specifying which version he didn't like and not extrapolating that to anything else, which is why the callout seemed weird.
The DHF and Mary definitely feel quite different, no argument there. There were definitely circumstances and conditions where the Mary outgripped the DHF (notably in deeper, softer soil) but I also found it to be more varied and less predictable in its performance depending across a range of conditions which was what gave me a hard time with it. Maybe I'd learn it better with more (a lot more) time on it and work around that, but it's not like I gave up on it after a ride or two.
I'm with you on the Dan (again, SG/Purple) though. That's a phenomenal wet condition tire.
@Udi why not pay a visit to this producer of 3d printed caliper based in NZ?
The alloy they use has half the yield strength of good old 7075 but they can put the material where it's needed.
It might just not be cheap...
The alloy they use has half the yield strength of good old 7075 but they can put the material where it's needed.
It might just not be cheap...