I've been hearing talk about the risks of re-setting the pistons while the system is closed. The risks to the bladder are very intuitive for me...
I've been hearing talk about the risks of re-setting the pistons while the system is closed. The risks to the bladder are very intuitive for me, but I am having trouble understanding how it is a risk to the main seal in the master cylinder. You wrote "If you reset the pads and don’t crack the bleed port you can easily blow the main seal too.". Can you clarify how that works? Intuitively, it seems to me that if the main seal is designed to contain the fluid's pressure, it shouldn't matter if the pressure is from the seal being pressed into the fluid (as when squeezing the brake lever) or if the pressure is from the fluid from the fluid pressing back on the seal (as when resetting the pistons).
When you squeeze the lever under normal braking, that pressure does not effect the seal in the masterThe main seal is only held in place by...
When you squeeze the lever under normal braking, that pressure does not effect the seal in the master
The main seal is only held in place by a weak plastic (sorry carbotecture) cap that is press into its place, If you force fluid back into the master (by resetting the pistons) it has nowhere to go and can easily blow that seal/cap... which is not replaceable
So it's not blowing the seal, it's breaking the piston/retention part.
Also the mineral oil vs. DOT question is precisely why dot is better than mineral oil. And the problems are because it is all "mineral" oil while quite possibly being about as different as DOT 5.1 is vs. DOT 5. Maybe selling it as "mineral oil 42xyz" would clear up these issues and would prevent some compatibility issues. You can put mineral engine oil in your car but if it was designed for 0W40 and you put 20W75 in it, the engine won't be happy. Even though it got mineral oil. With dot you have the exact specification you can and should put in.
Love Shimano and can’t wait for their new XTR/Saint brake to be released.I’ve Never had an issue with wandering bite on any of mine (expect my...
Love Shimano and can’t wait for their new XTR/Saint brake to be released.
I’ve Never had an issue with wandering bite on any of mine (expect my 3 year old Zees where you could see fluid ooze from the master) and every single one (that came through my workshops) we were able to fix with a decent bleed. Saw some failures form use of incompatible fluid though.
You can get any brake to wander with a shite bleed, no maintenance and neglect.
Why is it with mineral oil brakes people use any fluid except that which is recommended, whilst no one is stupid enough to put DOT 5 in their DOT4/5.1 brake and complain about it.
Great to hear! That wasn't my question though 🙂 I havn't experienced the wandering bite point in my last 5 sets of Shimano brakes either and like them a lot.
General question about how brakes work - what causes a seized piston, one that doesn’t move in the caliper when the lever is pulled? I understand...
General question about how brakes work - what causes a seized piston, one that doesn’t move in the caliper when the lever is pulled? I understand that the caliper seals essentially act as a spring, responsible for retracting the piston, and that the piston only slides within the seal when advancing to compensate for pad wear. If it is dirt that causes pistons to become stuck, how would dirt inhibit the caliper seal from flexing as the piston tries to extend?
Lotta options:
1. Piston crooked in bore. Sometimes this is obvious, other times not so much. Remedies: Push the piston back in straight by pushing on a couple sides. Worse case: install a pad on the opposite side and secure a pad spacer. Pump the brake to force the stuck piston to move and reset it after.
2. Debris. Typically happens after a good amount of use. Solutions: pump the piston out enough to clean it thoroughly. If the brake's had a helluva life, consider a caliper rebuild kit. When the caliper is split make sure to clean the bore and seal groove well with a soft bristle brush. A firm toothbrush generally works a treat.
3. Corrosion, primarily due to salts but pad dust can cause it as well over years, specifically sintered metallic pads. Caliper rebuild is in order, and you'll want to use something firmer than a toothbrush to break up the oxide layer. Plastic scraping tools are the way to go as you do not want to mess up the seal seat or bore dimensions.
4. Tolerance stack issue. If the caliper uses phenolic or ceramic pistons, the issue is more than likely an under sized bore or seal seat. Metal pistons may be oversized. This would be time to contact tech support.
EDIT: One more:
5. Contamination. IE the incorrect fluid finds its way into the system, either by bleeding it with an incompatible fluid (DOT fluid in a mineral oil brake and vice versa) or using a bleed kit that was used with both fluids. This will require a complete brake rebuild or replacement.
@Nobble Magura USA are NOT Magura! They are just a distributor. They are useless and I don’t know why Magura haven’t dropped them. Your symptoms generally only...
@Nobble Magura USA are NOT Magura! They are just a distributor. They are useless and I don’t know why Magura haven’t dropped them.
Your symptoms generally only happen if the system is overfilled or after a crash.
If you reset the pads and don’t crack the bleed port you can easily blow the main seal too.
Bleeding without the bleed blocks installed (and pads still in) causes overfilling.
It’s a common occurrence (for warranty depts) to see these cases and it’s always user error. Magura’s are a super simple bleed but the amount of PRO mechanics I’ve seen that try to bodge and do their own methods is ridiculous. And they always cause issues.
The mere fact that you’ve had such a high failure rate points to you being the common denominator.
Maguras carbotecture masters are a known weak point so you have to bleed and maintain them with that in mind.
I've been hearing talk about the risks of re-setting the pistons while the system is closed. The risks to the bladder are very intuitive for me...
I've been hearing talk about the risks of re-setting the pistons while the system is closed. The risks to the bladder are very intuitive for me, but I am having trouble understanding how it is a risk to the main seal in the master cylinder. You wrote "If you reset the pads and don’t crack the bleed port you can easily blow the main seal too.". Can you clarify how that works? Intuitively, it seems to me that if the main seal is designed to contain the fluid's pressure, it shouldn't matter if the pressure is from the seal being pressed into the fluid (as when squeezing the brake lever) or if the pressure is from the fluid from the fluid pressing back on the seal (as when resetting the pistons).
Couple things. If the brake is bled and maintained properly, there should be no risk of rupturing the diaphragm in the reservoir when resetting the caliper pistons. That becomes an issue when folx try to improve the lever feel by overfilling the system. The piston seals (MC & Caliper) shouldn't fail due to this simply because they're designed to handle a lot more pressure.
Can a system be overfilled by applying too much positive pressure using a syringe before closing the system? Can you share some tips on how not to overfill?
So it's not blowing the seal, it's breaking the piston/retention part.Also the mineral oil vs. DOT question is precisely why dot is better than mineral oil...
So it's not blowing the seal, it's breaking the piston/retention part.
Also the mineral oil vs. DOT question is precisely why dot is better than mineral oil. And the problems are because it is all "mineral" oil while quite possibly being about as different as DOT 5.1 is vs. DOT 5. Maybe selling it as "mineral oil 42xyz" would clear up these issues and would prevent some compatibility issues. You can put mineral engine oil in your car but if it was designed for 0W40 and you put 20W75 in it, the engine won't be happy. Even though it got mineral oil. With dot you have the exact specification you can and should put in.
We get it Primoz you don't like mineral oils. Sheesh mate, everytime
This debate can go on forever
The spec for bike brakes is quite simple: Shimano / Magura Royal Blood etc.
When you use the stuff the manufacturer recommends the issues are vastly reduced. There are more options for different brands of DOT4/5.1 because the market is HUUUGE. Very few oil producers even know bikes exist so they're not going to produce a tiny quantity of fluid because someone doesn't want to buy a bottle with Shimano on the side. Whether you like it or not its easier to do what each brake manufacturer recommends.
I've seen both the seal and the retaining cap blown/cracked/damaged.
Can a system be overfilled by applying too much positive pressure using a syringe before closing the system? Can you share some tips on how not...
Can a system be overfilled by applying too much positive pressure using a syringe before closing the system? Can you share some tips on how not to overfill?
That is exactly the #1 way a brake gets overfilled, 2nd to not resetting the pistons prior to starting a bleed. Easy to remedy. Take the hose off the syringe. Set the master cylinder up in the manufacturer's recommended bleed position and attach the hose to the bleed port. Push the caliper pistons back into their bores and this will burp out the excess fluid. You may want to wrap the hose in a bit of paper towel or a rag in case there's a lot of fluid in the system and it overflows the hose. Remove hose, install bleed port screw, clean with isopropyl (DOT) or a bit of soapy water (Mineral). Set the brake up as per instructions. Always RTFM a couple times with any brake. A lot of tips & tricks can be deduced from what the manufacturer recommends for service and it'll provide at least something indicating a flow path through the caliper and master cylinder. That bit there is a VERY valuable bit of insight.
That's good intel. Being a long time SRAM user those are two things I have a habit of doing. Over pressurize the crap out of the system to get that crisp bite point and resetting pistons without opening the system before bleeds. Never had issues across their entire MTB range. Turns out not all brake systems are that forgiving.
That's good intel. Being a long time SRAM user those are two things I have a habit of doing. Over pressurize the crap out of the...
That's good intel. Being a long time SRAM user those are two things I have a habit of doing. Over pressurize the crap out of the system to get that crisp bite point and resetting pistons without opening the system before bleeds. Never had issues across their entire MTB range. Turns out not all brake systems are that forgiving.
Can second this, I ran multiple sets of overpressurized codes for a couple of seasons and never had an issue with burst diaphrams but have seen countless shimano/magura/etc with that issue. Blew my buddies mind when I bled/over pressured his trashed Code's. Fortunately don't have to deal with that now that I'm on Hope lol.
That's good intel. Being a long time SRAM user those are two things I have a habit of doing. Over pressurize the crap out of the...
That's good intel. Being a long time SRAM user those are two things I have a habit of doing. Over pressurize the crap out of the system to get that crisp bite point and resetting pistons without opening the system before bleeds. Never had issues across their entire MTB range. Turns out not all brake systems are that forgiving.
Most brake systems don't need to be over pressurized to make them feel OK haha. I've done that with a ton of Sram brakes, it's bassically a habit now when ever I bleed them, and I've not seen any issues at the master cylinder. I haven't really tried it with brakes from other brands since their feel was generally better IMO. I wish sram would drop the G2 or 4 piston level brakes and just have the 2 piston levels, the codes / DB8, and the Mavens.
When you add pressure to a brake system, this will result in the caliper pistons move, and continues moving until it meets a force that matches than pressure? Like, does "pressurize" in this conversation actually mean over fill?
The spring/magnet add a little force, but from my understanding i just can't understand how the over pressure is possible with out the pads hitting the rotor.
Great to hear! That wasn't my question though 🙂 I havn't experienced the wandering bite point in my last 5 sets of Shimano brakes either and...
Great to hear! That wasn't my question though 🙂 I havn't experienced the wandering bite point in my last 5 sets of Shimano brakes either and like them a lot.
Nah, I was just answering to your perception and of the Shimano hate.
I also forgto to metion that it looks like they’re developing a new fluid as some of the recent spy shots showed a different fluid than their standard pink. Maybe their standard isn’t upto the demands of a modern brake and it needs improvement or maybe the Syndicate were just using their own preferred fluid.
Over pressurize the brakes?When you add pressure to a brake system, this will result in the caliper pistons move, and continues moving until it meets a...
Over pressurize the brakes?
When you add pressure to a brake system, this will result in the caliper pistons move, and continues moving until it meets a force that matches than pressure? Like, does "pressurize" in this conversation actually mean over fill?
The spring/magnet add a little force, but from my understanding i just can't understand how the over pressure is possible with out the pads hitting the rotor.
Yep, overfilling=pressurizing. It inflates the diaphragm in the reservoir creating a positive pressure on the system rather than a neutral/slight vacuum with the lever released/at home position. In turn, it shrinks any air pocket(s) and even forces the air to dissolve into the fluid. This is all to say that the likely culprit was a bad bleed in the first place, but having improperly set caliper pistons (i.e. not lubed proper) can cause a similar light feel as the pistons will retract too much. Not a fan of the process as in true worse case scenarios it can result in a brake locking up as the fluid maxes out the res space and in turn cause the pistons to extend. Pressure cooker if you will.
Of note, pressurizing the system won't necessarily cause the pistons to advance as that depends on how hard the syringe is pushed prior to closing the caliper off.
How do you overfill? For example when I bled Codes and now bleed the Cominions the last step I do is push down the plunger on the lever side syringe with a bleed block in so the pistons don't advance and pressurize the system. This of course leads to fluid leaking out when I remove the syringe before I get the lever screw back in but that's a full as I can make the system.
Do you fill to the point the pistons begin to extend, then close the system and retract the pistons into the calipers?
How do you overfill? For example when I bled Codes and now bleed the Cominions the last step I do is push down the plunger on...
How do you overfill? For example when I bled Codes and now bleed the Cominions the last step I do is push down the plunger on the lever side syringe with a bleed block in so the pistons don't advance and pressurize the system. This of course leads to fluid leaking out when I remove the syringe before I get the lever screw back in but that's a full as I can make the system.
Do you fill to the point the pistons begin to extend, then close the system and retract the pistons into the calipers?
with bleeding edge you can, after closing the lever, add some more fluid from the caliper and close the system
How do you overfill? For example when I bled Codes and now bleed the Cominions the last step I do is push down the plunger on...
How do you overfill? For example when I bled Codes and now bleed the Cominions the last step I do is push down the plunger on the lever side syringe with a bleed block in so the pistons don't advance and pressurize the system. This of course leads to fluid leaking out when I remove the syringe before I get the lever screw back in but that's a full as I can make the system.
Do you fill to the point the pistons begin to extend, then close the system and retract the pistons into the calipers?
Thinner bleed block if you don't have SRAM system.
I finally got myself a pair of Dominions, so I can compare them to my Cominions (Code RSC levers, Dominion A4 calipers).
The two setups have nothing in common except the calipers. Pads, rotors, and wheel sizes are all different. I can't make any useful observations about power. This post is all about feel.
Both levers are the same length from pivot to corner of the hook (70mm), but the Hayes pivot is inline with the bar clamp and SRAM positions the pivot point a bit outboard. So I run my dropper lever and shifter inboard with Hayes, and outboard with SRAM.
Lever height at the hook is about 15mm for Hayes and 14mm for Sram. But the Code lever actually feels taller, as its edges are more squared off. The SRAM hook feels a little more aggressive and, by eyeball, does look to angle a bit more. I like that because I run a bar with 12° backsweep. The Dominion is a more comfortable place to rest a finger, but I still think I like the SRAM lever shape better.
Throw length is very similar between the two. I didn't bother measuring this, as they're close enough I can't feel a difference. It seems the SRAM Swinglink vs. Hayes smaller MC (and whatever geometric differences) balance out.
The Dominion lever swings with significantly less resistance, though I should note I've never done any maintenance to the Codes, and I bet they could benefit from a rebuild. The Dominions have a crisper, more defined bite point. Both are easy to modulate with the Code lever's extra resistance making it feel a bit more intuitive. It's also the one I've been using for the last three years, can't ignore that muscle memory.
If you love the SRAM lever feel but want to give your Codes 20% more hydraulic leverage, adding Dominion A4 calipers will do exactly that. This frankenbrake works very well within the expectation that it still feels like an Avid/SRAM brake. I am impressed how it holds up against the proper, full Hayes setup. That said, you do need Dominion levers to get the famously light Dominion feel.
Hoping someone in this can help. I have a set of Hayes A4 and looking for options for integrated mixmaster setups. I have a oneup lever and SRAM t-type pod shifter. Any idea what the best options are out there to remove the clutter on the bars and put it on all the hayes?
So far it seems the Formula Mixmaster left should work with the Oneup lever as an option, but can't figure out if one of those would work with the pod, and can't find what ones may work. I might just go with the standard pod mount.
And slightly off my topic, but I just got a new 5010 and it came with Code Silvers + 180 HS2 rotors. I have a pair of Dominion A4s from black friday with 203+180 on hand, so trying to decide between the two. I'm currently leaning Hayes for the additional power, but let me know if I'm an idiot. Upvote for Hayes, Downvote for Code Silvers (adding 200 front).
Hoping someone in this can help. I have a set of Hayes A4 and looking for options for integrated mixmaster setups. I have a oneup lever...
Hoping someone in this can help. I have a set of Hayes A4 and looking for options for integrated mixmaster setups. I have a oneup lever and SRAM t-type pod shifter. Any idea what the best options are out there to remove the clutter on the bars and put it on all the hayes?
So far it seems the Formula Mixmaster left should work with the Oneup lever as an option, but can't figure out if one of those would work with the pod, and can't find what ones may work. I might just go with the standard pod mount.
And slightly off my topic, but I just got a new 5010 and it came with Code Silvers + 180 HS2 rotors. I have a pair of Dominion A4s from black friday with 203+180 on hand, so trying to decide between the two. I'm currently leaning Hayes for the additional power, but let me know if I'm an idiot. Upvote for Hayes, Downvote for Code Silvers (adding 200 front).
For the dropper side, Hayes Peacemaker works. Formula may work, you'll need to check fitment on how the bolt holes line up. For the shifter side, there is no adapter that will let you run a Pod on Hayes that I know of yet. Your best bet is to use the SRAM Infinite clamp (the figure 8 shaped one), it's very slim and light.
Speaking of Cominions.I finally got myself a pair of Dominions, so I can compare them to my Cominions (Code RSC levers, Dominion A4 calipers).The two setups...
Speaking of Cominions.
I finally got myself a pair of Dominions, so I can compare them to my Cominions (Code RSC levers, Dominion A4 calipers).
The two setups have nothing in common except the calipers. Pads, rotors, and wheel sizes are all different. I can't make any useful observations about power. This post is all about feel.
Both levers are the same length from pivot to corner of the hook (70mm), but the Hayes pivot is inline with the bar clamp and SRAM positions the pivot point a bit outboard. So I run my dropper lever and shifter inboard with Hayes, and outboard with SRAM.
Lever height at the hook is about 15mm for Hayes and 14mm for Sram. But the Code lever actually feels taller, as its edges are more squared off. The SRAM hook feels a little more aggressive and, by eyeball, does look to angle a bit more. I like that because I run a bar with 12° backsweep. The Dominion is a more comfortable place to rest a finger, but I still think I like the SRAM lever shape better.
Throw length is very similar between the two. I didn't bother measuring this, as they're close enough I can't feel a difference. It seems the SRAM Swinglink vs. Hayes smaller MC (and whatever geometric differences) balance out.
The Dominion lever swings with significantly less resistance, though I should note I've never done any maintenance to the Codes, and I bet they could benefit from a rebuild. The Dominions have a crisper, more defined bite point. Both are easy to modulate with the Code lever's extra resistance making it feel a bit more intuitive. It's also the one I've been using for the last three years, can't ignore that muscle memory.
If you love the SRAM lever feel but want to give your Codes 20% more hydraulic leverage, adding Dominion A4 calipers will do exactly that. This frankenbrake works very well within the expectation that it still feels like an Avid/SRAM brake. I am impressed how it holds up against the proper, full Hayes setup. That said, you do need Dominion levers to get the famously light Dominion feel.
I owned codes before getting dominions. All I'd say is that it took me a while to get used to the light lever action and I found myself locking up unintentionally a lot to begin with. Several months on, however, my fingers are reprogrammed and it's second nature and I'm reaping the rewards with 1. less hand/arm fatigue and 2. More confidence because there's just silly amounts of braking power available on tap with very little effort.
You'll learn to modulate over time if you stick with it.
Hoping someone in this can help. I have a set of Hayes A4 and looking for options for integrated mixmaster setups. I have a oneup lever...
Hoping someone in this can help. I have a set of Hayes A4 and looking for options for integrated mixmaster setups. I have a oneup lever and SRAM t-type pod shifter. Any idea what the best options are out there to remove the clutter on the bars and put it on all the hayes?
So far it seems the Formula Mixmaster left should work with the Oneup lever as an option, but can't figure out if one of those would work with the pod, and can't find what ones may work. I might just go with the standard pod mount.
And slightly off my topic, but I just got a new 5010 and it came with Code Silvers + 180 HS2 rotors. I have a pair of Dominion A4s from black friday with 203+180 on hand, so trying to decide between the two. I'm currently leaning Hayes for the additional power, but let me know if I'm an idiot. Upvote for Hayes, Downvote for Code Silvers (adding 200 front).
You could run Hayes Peacemaker adapter to matchmaker and then run Bikeyoke or 612 parts Matchmaker to Transmission Pod adapter
Plastic coated Goodridge hoses or raw ones? The first ones are 6mm while the raw ones are 5mm I.e. same as their kevlar hose.
This season I ran the coated Goodridge hose for front and beta hose in rear due to the Specialized Enduro hose routing limitation. I found the bite point to be not as firm when using the kevlar hose. Difference is pretty small and the sheer power of the brakes don't let you notice that as much. Which frame? Apparently some frames like Yetis clear the thicker coated hoses.
Hoping someone in this can help. I have a set of Hayes A4 and looking for options for integrated mixmaster setups. I have a oneup lever...
Hoping someone in this can help. I have a set of Hayes A4 and looking for options for integrated mixmaster setups. I have a oneup lever and SRAM t-type pod shifter. Any idea what the best options are out there to remove the clutter on the bars and put it on all the hayes?
So far it seems the Formula Mixmaster left should work with the Oneup lever as an option, but can't figure out if one of those would work with the pod, and can't find what ones may work. I might just go with the standard pod mount.
And slightly off my topic, but I just got a new 5010 and it came with Code Silvers + 180 HS2 rotors. I have a pair of Dominion A4s from black friday with 203+180 on hand, so trying to decide between the two. I'm currently leaning Hayes for the additional power, but let me know if I'm an idiot. Upvote for Hayes, Downvote for Code Silvers (adding 200 front).
I ran into similar issues with my AXS and dropper, ended up with a wolftooth shiftmount for magura and a magura shiftmix and it fit on my dominions perfectly.
Plastic coated Goodridge hoses or raw ones? The first ones are 6mm while the raw ones are 5mm I.e. same as their kevlar hose.This season I...
Plastic coated Goodridge hoses or raw ones? The first ones are 6mm while the raw ones are 5mm I.e. same as their kevlar hose.
This season I ran the coated Goodridge hose for front and beta hose in rear due to the Specialized Enduro hose routing limitation. I found the bite point to be not as firm when using the kevlar hose. Difference is pretty small and the sheer power of the brakes don't let you notice that as much. Which frame? Apparently some frames like Yetis clear the thicker coated hoses.
I didn't realize there were even more options for the Goodridge hose. live in the PNW, so exposed metal seems like maybe not the best idea... They have to be coating it for a reason?
I have had a couple bikes with relatively tight tube in tube routing, so it may be best to go for the kevlar.
I didn't realize there were even more options for the Goodridge hose. live in the PNW, so exposed metal seems like maybe not the best idea...
I didn't realize there were even more options for the Goodridge hose. live in the PNW, so exposed metal seems like maybe not the best idea... They have to be coating it for a reason?
I have had a couple bikes with relatively tight tube in tube routing, so it may be best to go for the kevlar.
It is a stainless steel mesh so you don't really need to worry about corrosion. The two downsides are
a) It is extra work to cut it because the ends fray. You need to use heat shrink tubing on the cut mark.
b) The exposed metal doubles as a file. It is abrasive and any frame rub won't be pretty. Just requires careful planning.
Hoping someone in this can help. I have a set of Hayes A4 and looking for options for integrated mixmaster setups. I have a oneup lever...
Hoping someone in this can help. I have a set of Hayes A4 and looking for options for integrated mixmaster setups. I have a oneup lever and SRAM t-type pod shifter. Any idea what the best options are out there to remove the clutter on the bars and put it on all the hayes?
So far it seems the Formula Mixmaster left should work with the Oneup lever as an option, but can't figure out if one of those would work with the pod, and can't find what ones may work. I might just go with the standard pod mount.
And slightly off my topic, but I just got a new 5010 and it came with Code Silvers + 180 HS2 rotors. I have a pair of Dominion A4s from black friday with 203+180 on hand, so trying to decide between the two. I'm currently leaning Hayes for the additional power, but let me know if I'm an idiot. Upvote for Hayes, Downvote for Code Silvers (adding 200 front).
I've used the Wolftooth magura shift mix with my Hayes brakes to run a sram mechanical shifter and an MMX compatible dropper post lever. The alignment isn't perfect, but it's close enough to get proper torque and to not ruin the bolts.
Plastic coated Goodridge hoses or raw ones? The first ones are 6mm while the raw ones are 5mm I.e. same as their kevlar hose.This season I...
Plastic coated Goodridge hoses or raw ones? The first ones are 6mm while the raw ones are 5mm I.e. same as their kevlar hose.
This season I ran the coated Goodridge hose for front and beta hose in rear due to the Specialized Enduro hose routing limitation. I found the bite point to be not as firm when using the kevlar hose. Difference is pretty small and the sheer power of the brakes don't let you notice that as much. Which frame? Apparently some frames like Yetis clear the thicker coated hoses.
If the coated vs. uncoated hose is the same except for the coating, the rubberized layer on top of it has no effect on the feel of the brake. The rear being mushier is connected to the longer length of the hose acting as a softer spring vs. to front brake. This is a well known thing with WC riders running brake contact of the rear brake quicker to compensate for this difference.
If the coated vs. uncoated hose is the same except for the coating, the rubberized layer on top of it has no effect on the feel...
If the coated vs. uncoated hose is the same except for the coating, the rubberized layer on top of it has no effect on the feel of the brake. The rear being mushier is connected to the longer length of the hose acting as a softer spring vs. to front brake. This is a well known thing with WC riders running brake contact of the rear brake quicker to compensate for this difference.
I think he was comparing kevlar vs braided ss hoses.
So it's not blowing the seal, it's breaking the piston/retention part.
Also the mineral oil vs. DOT question is precisely why dot is better than mineral oil. And the problems are because it is all "mineral" oil while quite possibly being about as different as DOT 5.1 is vs. DOT 5. Maybe selling it as "mineral oil 42xyz" would clear up these issues and would prevent some compatibility issues. You can put mineral engine oil in your car but if it was designed for 0W40 and you put 20W75 in it, the engine won't be happy. Even though it got mineral oil. With dot you have the exact specification you can and should put in.
Great to hear! That wasn't my question though 🙂 I havn't experienced the wandering bite point in my last 5 sets of Shimano brakes either and like them a lot.
Lotta options:
1. Piston crooked in bore. Sometimes this is obvious, other times not so much. Remedies: Push the piston back in straight by pushing on a couple sides. Worse case: install a pad on the opposite side and secure a pad spacer. Pump the brake to force the stuck piston to move and reset it after.
2. Debris. Typically happens after a good amount of use. Solutions: pump the piston out enough to clean it thoroughly. If the brake's had a helluva life, consider a caliper rebuild kit. When the caliper is split make sure to clean the bore and seal groove well with a soft bristle brush. A firm toothbrush generally works a treat.
3. Corrosion, primarily due to salts but pad dust can cause it as well over years, specifically sintered metallic pads. Caliper rebuild is in order, and you'll want to use something firmer than a toothbrush to break up the oxide layer. Plastic scraping tools are the way to go as you do not want to mess up the seal seat or bore dimensions.
4. Tolerance stack issue. If the caliper uses phenolic or ceramic pistons, the issue is more than likely an under sized bore or seal seat. Metal pistons may be oversized. This would be time to contact tech support.
EDIT: One more:
5. Contamination. IE the incorrect fluid finds its way into the system, either by bleeding it with an incompatible fluid (DOT fluid in a mineral oil brake and vice versa) or using a bleed kit that was used with both fluids. This will require a complete brake rebuild or replacement.
Couple things. If the brake is bled and maintained properly, there should be no risk of rupturing the diaphragm in the reservoir when resetting the caliper pistons. That becomes an issue when folx try to improve the lever feel by overfilling the system. The piston seals (MC & Caliper) shouldn't fail due to this simply because they're designed to handle a lot more pressure.
Can a system be overfilled by applying too much positive pressure using a syringe before closing the system? Can you share some tips on how not to overfill?
We get it Primoz you don't like mineral oils. Sheesh mate, everytime
This debate can go on forever
The spec for bike brakes is quite simple: Shimano / Magura Royal Blood etc.
When you use the stuff the manufacturer recommends the issues are vastly reduced. There are more options for different brands of DOT4/5.1 because the market is HUUUGE. Very few oil producers even know bikes exist so they're not going to produce a tiny quantity of fluid because someone doesn't want to buy a bottle with Shimano on the side. Whether you like it or not its easier to do what each brake manufacturer recommends.
I've seen both the seal and the retaining cap blown/cracked/damaged.
That is exactly the #1 way a brake gets overfilled, 2nd to not resetting the pistons prior to starting a bleed. Easy to remedy. Take the hose off the syringe. Set the master cylinder up in the manufacturer's recommended bleed position and attach the hose to the bleed port. Push the caliper pistons back into their bores and this will burp out the excess fluid. You may want to wrap the hose in a bit of paper towel or a rag in case there's a lot of fluid in the system and it overflows the hose. Remove hose, install bleed port screw, clean with isopropyl (DOT) or a bit of soapy water (Mineral). Set the brake up as per instructions. Always RTFM a couple times with any brake. A lot of tips & tricks can be deduced from what the manufacturer recommends for service and it'll provide at least something indicating a flow path through the caliper and master cylinder. That bit there is a VERY valuable bit of insight.
That's good intel. Being a long time SRAM user those are two things I have a habit of doing. Over pressurize the crap out of the system to get that crisp bite point and resetting pistons without opening the system before bleeds. Never had issues across their entire MTB range. Turns out not all brake systems are that forgiving.
Can second this, I ran multiple sets of overpressurized codes for a couple of seasons and never had an issue with burst diaphrams but have seen countless shimano/magura/etc with that issue. Blew my buddies mind when I bled/over pressured his trashed Code's. Fortunately don't have to deal with that now that I'm on Hope lol.
Most brake systems don't need to be over pressurized to make them feel OK haha. I've done that with a ton of Sram brakes, it's bassically a habit now when ever I bleed them, and I've not seen any issues at the master cylinder. I haven't really tried it with brakes from other brands since their feel was generally better IMO. I wish sram would drop the G2 or 4 piston level brakes and just have the 2 piston levels, the codes / DB8, and the Mavens.
Over pressurize the brakes?
When you add pressure to a brake system, this will result in the caliper pistons move, and continues moving until it meets a force that matches than pressure? Like, does "pressurize" in this conversation actually mean over fill?
The spring/magnet add a little force, but from my understanding i just can't understand how the over pressure is possible with out the pads hitting the rotor.
Nah, I was just answering to your perception and of the Shimano hate.
I also forgto to metion that it looks like they’re developing a new fluid as some of the recent spy shots showed a different fluid than their standard pink. Maybe their standard isn’t upto the demands of a modern brake and it needs improvement or maybe the Syndicate were just using their own preferred fluid.
Yep, overfilling=pressurizing. It inflates the diaphragm in the reservoir creating a positive pressure on the system rather than a neutral/slight vacuum with the lever released/at home position. In turn, it shrinks any air pocket(s) and even forces the air to dissolve into the fluid. This is all to say that the likely culprit was a bad bleed in the first place, but having improperly set caliper pistons (i.e. not lubed proper) can cause a similar light feel as the pistons will retract too much. Not a fan of the process as in true worse case scenarios it can result in a brake locking up as the fluid maxes out the res space and in turn cause the pistons to extend. Pressure cooker if you will.
Of note, pressurizing the system won't necessarily cause the pistons to advance as that depends on how hard the syringe is pushed prior to closing the caliper off.
How do you overfill? For example when I bled Codes and now bleed the Cominions the last step I do is push down the plunger on the lever side syringe with a bleed block in so the pistons don't advance and pressurize the system. This of course leads to fluid leaking out when I remove the syringe before I get the lever screw back in but that's a full as I can make the system.
Do you fill to the point the pistons begin to extend, then close the system and retract the pistons into the calipers?
with bleeding edge you can, after closing the lever, add some more fluid from the caliper and close the system
Thinner bleed block if you don't have SRAM system.
Thanks for the answers, I was concerned I had misinterpreted some instructions and been messing up my bleed this whole time.
Speaking of Cominions.
I finally got myself a pair of Dominions, so I can compare them to my Cominions (Code RSC levers, Dominion A4 calipers).
The two setups have nothing in common except the calipers. Pads, rotors, and wheel sizes are all different. I can't make any useful observations about power. This post is all about feel.
Both levers are the same length from pivot to corner of the hook (70mm), but the Hayes pivot is inline with the bar clamp and SRAM positions the pivot point a bit outboard. So I run my dropper lever and shifter inboard with Hayes, and outboard with SRAM.
Lever height at the hook is about 15mm for Hayes and 14mm for Sram. But the Code lever actually feels taller, as its edges are more squared off. The SRAM hook feels a little more aggressive and, by eyeball, does look to angle a bit more. I like that because I run a bar with 12° backsweep. The Dominion is a more comfortable place to rest a finger, but I still think I like the SRAM lever shape better.
Throw length is very similar between the two. I didn't bother measuring this, as they're close enough I can't feel a difference. It seems the SRAM Swinglink vs. Hayes smaller MC (and whatever geometric differences) balance out.
The Dominion lever swings with significantly less resistance, though I should note I've never done any maintenance to the Codes, and I bet they could benefit from a rebuild. The Dominions have a crisper, more defined bite point. Both are easy to modulate with the Code lever's extra resistance making it feel a bit more intuitive. It's also the one I've been using for the last three years, can't ignore that muscle memory.
If you love the SRAM lever feel but want to give your Codes 20% more hydraulic leverage, adding Dominion A4 calipers will do exactly that. This frankenbrake works very well within the expectation that it still feels like an Avid/SRAM brake. I am impressed how it holds up against the proper, full Hayes setup. That said, you do need Dominion levers to get the famously light Dominion feel.
Hoping someone in this can help. I have a set of Hayes A4 and looking for options for integrated mixmaster setups. I have a oneup lever and SRAM t-type pod shifter. Any idea what the best options are out there to remove the clutter on the bars and put it on all the hayes?
So far it seems the Formula Mixmaster left should work with the Oneup lever as an option, but can't figure out if one of those would work with the pod, and can't find what ones may work. I might just go with the standard pod mount.
And slightly off my topic, but I just got a new 5010 and it came with Code Silvers + 180 HS2 rotors. I have a pair of Dominion A4s from black friday with 203+180 on hand, so trying to decide between the two. I'm currently leaning Hayes for the additional power, but let me know if I'm an idiot. Upvote for Hayes, Downvote for Code Silvers (adding 200 front).
For the dropper side, Hayes Peacemaker works. Formula may work, you'll need to check fitment on how the bolt holes line up. For the shifter side, there is no adapter that will let you run a Pod on Hayes that I know of yet. Your best bet is to use the SRAM Infinite clamp (the figure 8 shaped one), it's very slim and light.
I owned codes before getting dominions. All I'd say is that it took me a while to get used to the light lever action and I found myself locking up unintentionally a lot to begin with. Several months on, however, my fingers are reprogrammed and it's second nature and I'm reaping the rewards with 1. less hand/arm fatigue and 2. More confidence because there's just silly amounts of braking power available on tap with very little effort.
You'll learn to modulate over time if you stick with it.
You could run Hayes Peacemaker adapter to matchmaker and then run Bikeyoke or 612 parts Matchmaker to Transmission Pod adapter
https://r2-bike.com/612-PARTS-Matchmaker-Podapter-SRAM-Transmission-Adapter-black
Does anybody have direct experience to using the thinner, kevlar tubing on Maxima brakes?
Overall, I really dig the idea of the Goodridge hose, but frame compatibility is something I don't want to have to fight with.
There wasn't much on the website in terms of performance loss, so I'm just wondering what the difference actually is?
Plastic coated Goodridge hoses or raw ones? The first ones are 6mm while the raw ones are 5mm I.e. same as their kevlar hose.
This season I ran the coated Goodridge hose for front and beta hose in rear due to the Specialized Enduro hose routing limitation. I found the bite point to be not as firm when using the kevlar hose. Difference is pretty small and the sheer power of the brakes don't let you notice that as much. Which frame? Apparently some frames like Yetis clear the thicker coated hoses.
I ran into similar issues with my AXS and dropper, ended up with a wolftooth shiftmount for magura and a magura shiftmix and it fit on my dominions perfectly.
I didn't realize there were even more options for the Goodridge hose. live in the PNW, so exposed metal seems like maybe not the best idea... They have to be coating it for a reason?
I have had a couple bikes with relatively tight tube in tube routing, so it may be best to go for the kevlar.
It is a stainless steel mesh so you don't really need to worry about corrosion. The two downsides are
a) It is extra work to cut it because the ends fray. You need to use heat shrink tubing on the cut mark.
b) The exposed metal doubles as a file. It is abrasive and any frame rub won't be pretty. Just requires careful planning.
But yeah kevlar hose is easier to deal with.
I've used the Wolftooth magura shift mix with my Hayes brakes to run a sram mechanical shifter and an MMX compatible dropper post lever. The alignment isn't perfect, but it's close enough to get proper torque and to not ruin the bolts.
If the coated vs. uncoated hose is the same except for the coating, the rubberized layer on top of it has no effect on the feel of the brake. The rear being mushier is connected to the longer length of the hose acting as a softer spring vs. to front brake. This is a well known thing with WC riders running brake contact of the rear brake quicker to compensate for this difference.
I think he was comparing kevlar vs braided ss hoses.
Post a reply to: Nerding out on Brakes shall we? Not another tech deraliment