That may be true but who's really at fault is that cousin that's home from Uni for the holidays. You know.... the one that decided to major in liberal arts. Well ever since he's taken Philosophy 101 with that professor, he's been looking to debate and impart his 'wisdom' to anyone at the dinner table. That professor being the one that asks the BIG questions, but is actually more or less only interested in playing it cool to hook up casually with the female student body...
Frankenbrakes and brake improvement discussion
- Thread starter Udi
- Start date
Has anyone ever had a rear brake REALLY wail due to it matching the resonant frequency of the frame? My Ti 26 hardtail is howling like a stuck pig when I feather the rear brake. Full lock is not an issue.
I'm running 810 Saints with an 8 inch rotor. Bolts are all tight. Pads are fresh and uncontaminated.
Any suggestions? I imagine changing up the weight of some or all of the components would be critical, but which ones?
Different adaptor? Adding weight/ballast to the existing adaptor (hello Chris Porter!)? Would my upcoming new wheelset (much lighter) do the trick? 7 inch rotor?
Cheers all!
I'm running 810 Saints with an 8 inch rotor. Bolts are all tight. Pads are fresh and uncontaminated.
Any suggestions? I imagine changing up the weight of some or all of the components would be critical, but which ones?
Different adaptor? Adding weight/ballast to the existing adaptor (hello Chris Porter!)? Would my upcoming new wheelset (much lighter) do the trick? 7 inch rotor?
Cheers all!
Yes, one sram 180mm rotor does that on my carbon HT frame. I couldn't find other solution than replacing the rotor.
Ok, so did you get a new 180mm rotor? Or a different sized rotor?
Couple of quick questions.
Anyone got any time on these newer style rotors?
Apparently they're stiffer than the old style, which might also go a ways to stopping squeal. They're pretty cheap over at wiggle, so I'm thinking of pulling the trigger.
Also, how are the newer Zees? Asking any long term users, especially in terms of power and reliability.... Sorry if this has been asked before but I couldn't find anything of substance.
Anyone got any time on these newer style rotors?
Apparently they're stiffer than the old style, which might also go a ways to stopping squeal. They're pretty cheap over at wiggle, so I'm thinking of pulling the trigger.
Also, how are the newer Zees? Asking any long term users, especially in terms of power and reliability.... Sorry if this has been asked before but I couldn't find anything of substance.
They look slightly different, but I've not been able to tell any difference in performance between these and the older ones. That's a good thing - the old ones worked fine for me.
^^
That's been my experience as well. Maybe the new ones are a little lighter?
As for the Zee's, I don't have a set, but I've fiddled around on @SuboptimusPrime 's various bikes which have them and they seemed like the what the intranets said about them - shit tonne of power, pretty on/off bite, fiddly to properly set up but with a good bleed they're good. A lot of people have claimed there's a wildly inconsistent bite point, but that might be related to a bad bleed. Moreover, there seems to be some issues with newer model Shimano brakes sucking in air over a relatively short period of time and/or the ceramic piston and seal not playing nice together which causes fluid leakage eventually.
I use some of those and my experience echos Olly & jackalope, no noticeable difference in grip, noise nor fade.
As jackalope said, I've got two sets and both have been overall quite reliable. I've had very rare bite point weirdness on the set that is on my DH bike, now 3 seasons old. They never pulled to the bar, but sometimes the bite point would be further out. Again, this has happened very infrequently. I agree they are plenty powerful but not great modulation wise---if you grab a handful of brake in a hamfisted way, you're gonna lock up your wheels. I don't really notice it because I'm used to it and can modulate just fine using judicious pressure on the lever. Funny thing is, when I ride on brakes with good modulation (like jackalopes TRPs) they feel weak to me at first even when they have totally adequate power when you pull the lever deeper into its travel. The feeling goes away if I ride for a bit and recalibrate my fingers. Just goes to show how subjective opinions are colored by what you are used to.
Bottom line: for the money, a damn good set of brakes in my experience esp if you need real power for DH. If you need perfect ergonomics, power and modulation to be happy, look elsewhere.
To be fair, I think the main problem is the ubiquitous brake rotor has not been properly optimized for the modern bio-cycle. In my (reptilian) opinion, rotors need to be designed for specific uses such as Endureu , boring WC tracks that the average Monkey could destroy, casual trail riding, aggressive trail riding (i.e. "hooning"), All-Mountain sans east coast roxxx, All-Mountain with east coast roxxx, XC racing sans EPO (if such a thing exists), XC racing with EPO, fat biking in snow, fat biking while getting punched by Eddie Masters, etc...
Of course one might assume you could simply use rotor size (200/180/160) to help determine which is the appropriate option for the given application, and to a degree, I support this idea. But only 3 main size options? Really? Have we learned nothing from Sram and Trek? What about 194mm for easy WC tracks? 307mm for Val Di Sol? 112 mm for a casual ride with the girlfriend? There's a veritable galaxy of possibilities here gents.
And lets not forget about kit colours. You like purple ano, ammirite? What about purple ano rotors? Again, think of the possibilities.
Needless to say, we would also want to change bolt hole patterns as well to gain a 0.04% increase in stiffness and other undetectable "performance benefits".
Then the proverbial purple ano cherry on top would be to charge 300% moar for this serious advancement in technology.
Btw, anyone know if Sram needs a new "Product Marketing Manager"?
I've been using those ever since they came out. No weirdness. The centerlock ones that were right before those used to come loose at the rivets for some reason but I've never had the bolt ons do it.
I've had some of them for quite a while now and if there's anything different, they might warp a little easier. The only thing I can think as of why is that there's less continuous steel to dissipate heat. I've usually got 3 bikes going and if anything it seems like the solid ones stay straighter a little longer.
They don't squeal but neither do any of the shimanos I've ever had unless they get some crap on them...which just burns off after a run or two.
I'd bet that the warping is due to the disparate thermal expansion between the stainless and aluminum inducing some stress in them when they get hot.
I like them though. Have them on all of my bikes at this point.
Yeah. I've kind of just been buying them because I know I don't hate them and am playing it safe, but I wouldn't rip something else off a new bike to replace with the Shimanos unless proven shitty.
WHO WOULD HAVE THOUGHT?!
Hope have already got you covered there.
I've got really high hopes for those things. I've ridden the 2 pots on a friend's bike a bit, and the lever feel is really good, but if anything they've got a little bit too short a lever throw for my taste. I can't think of anything I've ever tried with as little. They're cheap and have held up great for him, so if they can add a bit of power and a little longer throw on the 4 pots they should have a winner.
Keep an eye on bike24's and bikecomponents' stock. They usually reorder a limited number of the black ones and if you're lucky you can get a brake much faster than going through Trickstuff - that's how Udi got his.
That doesn't sound good, i made a few calls to Trickstuff last year and they said their main goal for 2018 was to reduce lead times on the Diretissima - sounds like they actually got worse.
Technically he stole one off my wind trainer bike.
I would advice you to test ride this before buying: their ergonomy is not for everyone...
I don't know. I just have the Trail version which felt odd even if the bite point was where I wanted... I couldn't get the lever and the gear lever where I wanted even with Magura shiftmix adaptors. I might be picky and I might have gotten used to it if I didn't had another bike with a better fitting setup which remained me how poor/different the other setup was. I ended up with switching to Shimano levers which gave me wonderful ergonomy with a slight touch of changing break point.
Magura calipers - 
. Magura levers - 
. Magura levers -
They're truly horrible levers in every sense - the build quality is as awful as the ergonomics and they'll fall apart in a few crashes. If you were reasonably happy with the V4s previously, I'd just buy them again. Maguras have power but little else.
So, XT M-785's- a buddy gave me his bike to bleed these things. I read the Shimano manual and watched 2 videos on YouTube that were by reliable sources. IIhooked up the syringe and did the bottom-up bleed. Air came out and the lever felt great. The pads were worn, but still had some life left on them. I must have squeezed the lever over 200 times. The pads moved in, but wouldn't stay in. I redid the bleed, but still, no go. What's going on?
Last edited:
Are you squeezing with the caliper removed from the rotor?
If so, the pistons/seals might be a bit sticky - you can clean then lube them with some mineral oil, then push all the way in to get the oil to the seals and try pumping the lever again (repeat a few times). You can also force the pistons to come out with the syringe provided the hose is ziptied to both your syringe and the nipple tightly (with the lever held compressed, eg. ziptie), but if you don't know what you're doing this can end in a big mess.
Goes without saying, make sure the pads and rotor are not nearby while doing this, and clean the caliper with alcohol once done. Also it's best to bleed with new pads because if you bleed the system full with old pads, the system will be overfilled and will need to be drained to fit new pads later.
Both pistons move equally and at the same time, but they're not moving in and staying in. I removed the screw on the resivour to see if any fluid was getting pushed down to the caliper or if it was leaking somewhere, but it stayed topped off.
Fwiw, I've bled Avid/sram, Hayes and Hope before without any issues.
The owner said that every time he takes his bike out he has to pump the brakes till they engage before every ride. Fwiw, new pads are on the way, but I figured that if it was a good bleed, the old pads should work for now.
Fwiw, I've bled Avid/sram, Hayes and Hope before without any issues.
The owner said that every time he takes his bike out he has to pump the brakes till they engage before every ride. Fwiw, new pads are on the way, but I figured that if it was a good bleed, the old pads should work for now.
Last edited:
I have a video i'd like to post. After washing the bike off, when I squeezed the levers, air bubbles came out of the resivour toward the hose side. It makes me wonder if this is where air gets in to the majority of Shimano brakes.
Last edited:
I don't think you read my post at all.