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I only use brake cleaner for the disc as its more aggressive than isopropyl alcohol. But I always could save the disc. Only had to throw away the pads.
Galfer makes some great cheap 2.0 rotors. Seems like you are getting heat build/contact from the 2.3
I was told by MTX if you have contamination to use acetone and its a bit more aggressive than isopropyl. I believe you can try that on the pads too and sand them down as well, but don't quote me on that.
I use isopropyl alcohol and 80 to 180 grit emery paper/cloth (just depends what I have on hand).
For the pads, soapy water in the sink (plug in). Rub the pads against each other. Followed by just water, rubbing the pads together. Might take some rubbing (sometimes not long), but you know when they are done as the pads start gripping each other.
Has always worked for me.
Brake cleaner is a really strong solvent, for some things even stronger than acetone (cleaning an oil pan gasket sealer works really well while acetone hardly does anything). No worries about the strength of it.
Agreed with the others about it sounding like contaminated pads. What make and model of brake are they, how old, and when and what was the last service on em?
IME 'cleaning' pads after a contamination is a recipe for irritation. Pads are porous by nature, and any fluid that gets on em will seep into them during use. Cleaning removes the surface layer (and maybe some embedded) contaminant, and once the pads warm up the contaminant flows out to the braking surface, making the brake garbage again. Avoid the pratfall and pony up for new pads. Rotors can be cleaned without issue. I prefer contact cleaner or a strong isopropyl, 93% or better, as they leave less residue behind. A clean water wipe after isn't a bad idea either.
How about the good old gas burner for cleaning pads? Asking because fire is fun.
1. Semi mets/organics no go. You'll smoke the friction material in both (usually walnut shells believe it or not) while also smoking the adhesive used to hold the thing together and to the backing plate. Bad idea. Shucking corn = good, shucking pads = bad.
2. Sintered/ceramic. Never had luck with it. The problem always returned. I tried all the fixes I saw folx post, MAPP gas, stove top burner, broil the pads for an hour. Each ended up with a death grip to get the bike to slow. And noise. So much damn noise. The job that made me try all those wasn't glamorous, but it provided a lotta good insights. One of those was just to replace the pads when they're contaminated. No amount of fudgery is gonna bring em back to even 80% of their intended friction.
Has anyone ever seen these?
I’ve seen them in a custom build and got curious, never heard of the company
https://www.rideraicam.com/en/products/rgr-racing-brake-system/
No, I've never seen those before, and while we're talking about new MTB brake brands, I forget if we've already discussed these new HEL brakes earlier in this huge thread? https://www.bikemag.com/industry-news/hel-advocate-mountain-bike-brake
They claim some sort of special caliper fluid channel and piston design, but I'm unsure if that is just regular brake design that their marketing department is jazzing up as if it's unique.
That is a wild story about the steaks but I can totally see that happening after noticing little dots on my shirts whenever I'm cooking something in oil that sizzles, and seeing the little wet specks all over the stove area. That is a good thing to keep in mind for whenever I get back into the campervan life, as that could really ruin a trip, especially if you have limited time to ride and need to spend a lot of it fixing your brakes, or if you're in a rural area without the necessary replacement pads.
By the numbers presented I think they will be nothing special honestly
It happened. And you shouldn't really do that in a campervan anyway or it will smell really bad in no time. You should fry stuff outside or at least leave the side door open. But it was winter and he likes to cook...
I mean if you check thr extractor hood at home you'll notice that its covered in fat and in the campervan you usually don't have that and the heat makes little oil particles rising up in the air and they have to go somewhere. I also couldn't believe it at first but thank god I had extra pads.
I just installed my Radic Kaha brakes. I find that the rear pumps up pretty significantly (10mm). I've bled the brake perfectly to my knowledge, lubed the caliper pistons and tried pressurizing the system from the bleeding edge port etc. Is this due to the small orifices in the lever design or is there something I'm missing out on?
Your bleed is most likely not as perfect as you think it is.
Do you have any tips for me?
I bled them like this:
-Removed from bike.
-Wound contact point adjuster almost all the way out (there’s no stop in the adjuster at the fully wound out point).
-Pushed fluid from caliper up to the lever.
-Cycled the fluid back and forth about 5 times.
-Pushed out piston against a 4mm hex wrench and repeated cycling fluid back and forth.
-Pushed pistons back in.
-Zip tied lever to bar.
-Carefully pulled a little vacuum to draw any residual air from caliper.
-Pushed fluid from caliper up to the lever while releasing the zip tied lever slowly.
-Removed caliper syringe.
-Did a lever bleed by tilting it around and pushing and pulling on the syringe.
-Added positive pressure before removing lever syringe.
I have had good luck tapping on brake lines with a wrench while pushing/pulling fluid through the lines.
Definitely a bleed issue... I've been on the new, with contact point adjustment, brakes for about 6 months now. If you are not degassing the fluid before doing the bleed, you should. I also use fresh fluid on every bleed, I dont re-use old, opened containers (assuming that you are using DOT) The lever is pretty good at trapping bubbles, and they can be a pain to get out. Once you have pushed fluid from the caliper to the lever, close the caliper and pull a good vacuum from the lever syringe. I made a "tool" that lets me pull the vacuum and not have to keep holding it, its a spacer made from an old extra-long socket that I cut a slot on with a die-grinder, been using it for years! Once you have the vacuum pulled you can move the lever body around and tap on it to force any bubbles up into the syringe. Once you get it, its good, but I I did a quick bleed on them when I got them and had a pretty big oh sh*t moment the first ride out when the front brake went to the bar halfway down the mountain... Once you get it they are solid. I will say they are probably one of the more difficult brakes to bleed of any modern disc brake IMO, but once you get them dialed they are one of the best brakes I've ever had the pleasure of riding.
I also have found that its pretty important to bleed with the pads in while the brake is on the bike. It's in the instructions and I glossed over that when I first bled the brakes which could have been my problem. Ive found that there is a single position for my bike that magically helps to migrate bubbles to the lever, hanging front tire up in my bike storage system, so i bleed the brakes with the bike in that position in the stand. Once I learned that and re-bled them in that position I haven't had to touch them, 5+ months and lots of weekends on the lifts.
I’m running them with bionol so degassing won’t do me any favours afaik.
Also, what did you set the contact point adjustment to when bleeding them?
My current issues are:
Front brake reservoir membrane can’t handle pulling a vacuum. When I have a syringe connected to the lever and push positive pressure, it doesn’t leak from the vent hole. But if I pull on the syringe to create a vacuum, it sucks air in like crazy.
Rear brake can handle a vacuum but if I depress the lever while pulling the vacuum, it sucks air in just like the front brake.
The rear membrane leaked like crazy when I first bled it but removing and reinstalling the bladder seemed to fix it. I did the same to the front brake but it didn’t fix it.
Neither brake seems to leak from the master cylinder pistons and hose connections are all tight and not leaking.
I’m wondering if I have a bad set…
I truly wonder how components of this pricepoint can have these issues from new especially when they are hand built and tested.
Something doesn't sound right; I would reach out to Taylor. I can pull a vacuum strong enough to collapse the syringe line and not start sucking bubbles. Just out of curiosity what bleed kit are you using? I tried using an older Jagwire kit when I first got the brakes and ran into issues with the tapered port not sealing and sucking air from that interface, I ended up getting the Park pro kit, which works much better and made it possible to get a good bleed. I found that if I set the bite point two turns out from closing off the transfer port I get a good bleed and have plenty of adjustment to dial the bite to where I want.
Hope you get them sorted out!
I’ve sent Taylor multiple emails to explain the issues. I’m using a Jagwire elite bleed kit, the same he sells on the website so I thought it would be best.
I’m positive the leakage is not from the bleed kit since I can pull a strong vacuum with the same syringe on the rear but not on the front lever.
Sounds like they're still as fussy as ever 🙄 I fixed mine by selling them 🤣
I have no experience with the Radic brakes, but just wanted to chime in to say that, for all brake manufacturers, it would be a boon for both the consumer and the seller if they could: A: Deliver or suggest a bleed kit that will seal reliably under vacuum, and B: Design their brake so that the reservoir bladder/membrane (and MC seal!) can handle the negative pressure range generated by pulling on a syringe. I know many brakes can be bled "sufficiently" without negative pressure, but if you have ever watched a sticky bubble in a translucent line grow and shrink in response to +/- pressure, you will have seen how valuable it can be to vary the system pressure when bleeding the brake.
On a related note, what percentage of current brakes have a vent hole in the bladder/membrane? I can see why it is tempting to include one, to prevent over pressurization in odd circumstances, but it seems like it introduces as many problems as it solves. If I was designing a brake, I might be tempted to add one, but would only add it if it could be designed so it had a sort of exterior flap that would seal against the face of the membrane in neutral and negative pressure scenarios, but open in positive pressure scenarios.
What do you mean with the vent hole in the membrane?
There are vent holes in the membrane cover. The membrane can't have any holes in it.
Absolutely an informative thread. It took me two days to read it all.
I'm running Shimano Saint brakes with Shimano XT SM RT-86 203mm discs. My recipe for success has been that I change a new set of Shimano H03C metal disc brake pads every spring at the start of the season. My observation is that changing the pads is quite a cheap way to zeroize the free lever movement to near zero and get a good grip also during the season if some issues occur. I also keep the master cylinders pressurized during storage with velcro straps. A couple of random bleeds here and there also seem to keep the green liquid green and braking power in good shape.
My other bike (ebike) has Hayes Dominion A4 for trail riding. Their only problem has been that pads are so done that free lever movement is getting ridiculous. I think new pads would fix them also. In theory, it shouldn't be like this but my impression from bicycle brake is that anything can happen.
Question: I would like to the rotors from 203mm - > 220mm. The idea that I'm chasing is that with bigger rotors I would get the same braking power with less lever pull. It's more a curious test than a real critical need. Are there any specific rotors that would be valuable to look after?
Galfer 223mm sounds to be good. Braking Epta two-piece 2,2mm / 220mm would be nice looking but doesn't fit.
Running a bigger rotor achieves less finger force needed at the lever. But keep in mind that if you never get a 220mm rotor up to temperature, a 200mm rotor can have more power as it heats up faster.
I’ve ran:
Intend massive 223
Galfer Wave 223
Sram centerline 220
Sram HS2 220
Hope floating 220
TRP R1 223
Magura MDR-P 220
Out of all these I currently run the hopes. They’re thin at 1.8mm but due to the riveted design they’re the quietest rotors I’ve ever had. By quietest I meant it in the sense that they don’t ”ring” like 1-piece rotors.
I would run MDR-P’s but they don’t make the 220mm version in centerlock. (I hate that Chris King decided to make centerlock hubs only for 2022-2023 and then switched back to also making 6-bolt hubs).
The ringing is a really minor thing to most but when you otherwise have a completely quiet bike, I cant stand the ringing sound that happens when I’m off the brakes or when I drop my bike on the ground.
If you get a 1-piece rotor, make sure it’s as thick as it can be so it’ll be as rigid as possible. This is to reduce the likelyhood of warping. With a 2-piece/riveted rotor, the brake track thickness isn’t as crucial IMO as the carrier will provide the needed stiffness.
Anyone know the master cylinder diameter for mavens? Sorry if I missed this deeper in the thread
I think it's 9.5mm from memory
Have you considered centre lock adaptors and if so, what's your reason to avoid them?
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