Thanks to you guys who took an interest in my problem. Tonight I had a chance to take a closer look. I can't find any contamination...
Thanks to you guys who took an interest in my problem. Tonight I had a chance to take a closer look. I can't find any contamination nor pad overhang. The inside of the caliper is dry. Pads do look shiny, but on a test ride the brake has normal power, unlike when I glazed Sram metallics and half the power was gone.
What I did find is visual evidence of the pads moving forward and back a lot, consistent with the shudder I could feel. That's not brake fluid you see outlining the piston shapes, it's just the finish worn off.
My new idea is that some property of this specific pad & rotor pairing causes a grip-slip condition at higher temps. The MTX golds have more grab with some heat in them, so maybe there's a point where this interacts with the floating aspect of the rotor, even though said rotor doesn't seem loose.
Any smart people able to support or deny that? I'm just curious at this point - a pad and/or rotor swap seems like a likely cure if symptoms persist.
How'd you go about bedding the pads and rotor in? Rudimentary q, but better asked than not. It looks like you got the brake way hot causing a bit of glazing. NBD, sand the rotor surface some, clean with iso. As for pads, I don't recommend using sandpaper on em but the edge of a CLEAN file to scuff up the surface. Reason being the adhesive used in the sandpaper may cause a contamination issue. Rotors are easy enough to remove potential contaminants, but pads aren't due to their porous nature.
Contamination or glazing is a frustrating process.
I recently spoke with MTX on a similar issue, but with brand new pads. To reset the setup, they told me to sand the pads until the glaze is gone. I used 120 grit paper and not much material was taken off. No need for cleaning agent on them, just blow the material off. They recommended acetone on the rotors to clean them. You could also lightly sand the rotors then acetone again.
I never ended up getting the old one working as I wanted. It would fade at the 80-100% power range, especially when cold. MTX were great to work with though and sent me a new set of pads that are now working flawlessly. Its hard to say why my first set didn't work, maybe the bedding process, maybe some contamination, but they didn't care . Highly recommended company. This is the first pads I had had issues with having over a dozen used.
After resetting, use this bedding process. I found take your time on the bedding process. My theory is no stoppies until you've rode them for a couple rides and they are working well at all temps. And no water on the bedding process. I had read that with others doing that to ease the process, but maybe that gave me a bedding issue.
I once had a pair of Hope pads do exactly this - I was never able to figure out the source of the contamination or what went wrong in the first place, but I lost pretty much all braking friction with a fully glazed pad and that was all there was to it. Nothing I did could bring that set-up back. Fresh pair of pads solved the problem...
Maybe sometimes the pad compound just gets messed up from the factory, and "bleeds" resin under extreme heat or something.
Contamination or glazing is a frustrating process. I recently spoke with MTX on a similar issue, but with brand new pads. To reset the setup, they told...
Contamination or glazing is a frustrating process.
I recently spoke with MTX on a similar issue, but with brand new pads. To reset the setup, they told me to sand the pads until the glaze is gone. I used 120 grit paper and not much material was taken off. No need for cleaning agent on them, just blow the material off. They recommended acetone on the rotors to clean them. You could also lightly sand the rotors then acetone again.
I never ended up getting the old one working as I wanted. It would fade at the 80-100% power range, especially when cold. MTX were great to work with though and sent me a new set of pads that are now working flawlessly. Its hard to say why my first set didn't work, maybe the bedding process, maybe some contamination, but they didn't care . Highly recommended company. This is the first pads I had had issues with having over a dozen used.
After resetting, use this bedding process. I found take your time on the bedding process. My theory is no stoppies until you've rode them for a couple rides and they are working well at all temps. And no water on the bedding process. I had read that with others doing that to ease the process, but maybe that gave me a bedding issue.
I had a similar problem with MTX gold pads a couple months back on my XT/ZEE setup. Both pads would bed in well, then I'd a few minutes into a descent and immediately glaze the pads. I tried cleaning/sanding/rebedding 4 times and finally gave up. Contacted MTX and received friendly customer service but the guy couldn't give me an exact answer to my problem. The real solution was buying a set of T4 V4's lol.
I had a similar problem with MTX gold pads a couple months back on my XT/ZEE setup. Both pads would bed in well, then I'd a...
I had a similar problem with MTX gold pads a couple months back on my XT/ZEE setup. Both pads would bed in well, then I'd a few minutes into a descent and immediately glaze the pads. I tried cleaning/sanding/rebedding 4 times and finally gave up. Contacted MTX and received friendly customer service but the guy couldn't give me an exact answer to my problem. The real solution was buying a set of T4 V4's lol.
alot of braking things from wandering bite point & 'lever to far out' to fiddly setups would be solved buying t4v4 👌
I need help with choosing rotors. I currently run 223mm Trickstuff DH rotors F/R with Power+ pads. Under moderate to heavy braking they make the turkey gobble/warbling sound. Also when coasting down without pulling the brakes they make the awful ringing noise. I think this is mainly due to the 6 spoke design making the rotor quite flimsy in that regard.
My criteria for a rotor:
-223mm (I have +23mm Trickstuff adapters and I'm not going to buy new ones)
-Either Centerlock compatible or 6-bolt with the actual 6-bolt mounting part being under 2.2mm (I have centerlock hubs and DT Swiss centerlock adapters are rated for 2.2mm thick rotor mounting surface)
I'm interested in the Galfer Sharks. They come in 223mm and centerlock. To all you who run the 223mm shark rotors, do they "ring"?'
I need help with choosing rotors. I currently run 223mm Trickstuff DH rotors F/R with Power+ pads. Under moderate to heavy braking they make the turkey...
I need help with choosing rotors. I currently run 223mm Trickstuff DH rotors F/R with Power+ pads. Under moderate to heavy braking they make the turkey gobble/warbling sound. Also when coasting down without pulling the brakes they make the awful ringing noise. I think this is mainly due to the 6 spoke design making the rotor quite flimsy in that regard.
My criteria for a rotor:
-223mm (I have +23mm Trickstuff adapters and I'm not going to buy new ones)
-Either Centerlock compatible or 6-bolt with the actual 6-bolt mounting part being under 2.2mm (I have centerlock hubs and DT Swiss centerlock adapters are rated for 2.2mm thick rotor mounting surface)
I'm interested in the Galfer Sharks. They come in 223mm and centerlock. To all you who run the 223mm shark rotors, do they "ring"?'
My Sharks actually came slightly warped but I suspect that was postage rather than Galfer themselves since my Waves arrived perfect. Easy to straighten them back though and they've been perfect since then. Quieter than the Waves, slightly less aggressive feeling, but otherwise nothing to say really - they work as they should
I need help with choosing rotors. I currently run 223mm Trickstuff DH rotors F/R with Power+ pads. Under moderate to heavy braking they make the turkey...
I need help with choosing rotors. I currently run 223mm Trickstuff DH rotors F/R with Power+ pads. Under moderate to heavy braking they make the turkey gobble/warbling sound. Also when coasting down without pulling the brakes they make the awful ringing noise. I think this is mainly due to the 6 spoke design making the rotor quite flimsy in that regard.
My criteria for a rotor:
-223mm (I have +23mm Trickstuff adapters and I'm not going to buy new ones)
-Either Centerlock compatible or 6-bolt with the actual 6-bolt mounting part being under 2.2mm (I have centerlock hubs and DT Swiss centerlock adapters are rated for 2.2mm thick rotor mounting surface)
I'm interested in the Galfer Sharks. They come in 223mm and centerlock. To all you who run the 223mm shark rotors, do they "ring"?'
I need help with choosing rotors. I currently run 223mm Trickstuff DH rotors F/R with Power+ pads. Under moderate to heavy braking they make the turkey...
I need help with choosing rotors. I currently run 223mm Trickstuff DH rotors F/R with Power+ pads. Under moderate to heavy braking they make the turkey gobble/warbling sound. Also when coasting down without pulling the brakes they make the awful ringing noise. I think this is mainly due to the 6 spoke design making the rotor quite flimsy in that regard.
My criteria for a rotor:
-223mm (I have +23mm Trickstuff adapters and I'm not going to buy new ones)
-Either Centerlock compatible or 6-bolt with the actual 6-bolt mounting part being under 2.2mm (I have centerlock hubs and DT Swiss centerlock adapters are rated for 2.2mm thick rotor mounting surface)
I'm interested in the Galfer Sharks. They come in 223mm and centerlock. To all you who run the 223mm shark rotors, do they "ring"?'
some rotors, like shimano's terrible rt66 220 rotors vibrate & flex ALOT
aligned and straight rotors with any quality hub, The rotors will shake and vibrate so much they rub on the CALIPER when at speed.
these 220 rt66 rotors are also rubbish in performance, There is almost no stopping power difference between a 203 and rt66 220.... swapped out that rotor for a hs2 220 and it was soooo much better(i confirmed this by buying several rt66 220 when on spec) lucky they were cheap or id be pissed.
Those of you who have run both Sharks and Waves, what do you think about this idea? I'm trying to balance left / right lever feel. Both brakes a bled perfectly, fresh pads, etc. My right brake (across many brands / models) always feels a little bit softer at bite point, I suspect due to muscle imbalance L/R. I've already been running Sharks F/R and like them a lot, but reading the Galfer description it sounds like the Waves bite a little bit harder. So I was thinking of putting a Wave on back, just to balance the L/R lever feel at bite. The cons I see from Galfer's product page is that it'll wear pads faster (I burn rear pads faster regardless), and that they aren't as consistent with heat (I'm doing 2-3 min descents usually so I doubt that heat will really be an issue).
Those of you who have run both Sharks and Waves, what do you think about this idea? I'm trying to balance left / right lever feel...
Those of you who have run both Sharks and Waves, what do you think about this idea? I'm trying to balance left / right lever feel. Both brakes a bled perfectly, fresh pads, etc. My right brake (across many brands / models) always feels a little bit softer at bite point, I suspect due to muscle imbalance L/R. I've already been running Sharks F/R and like them a lot, but reading the Galfer description it sounds like the Waves bite a little bit harder. So I was thinking of putting a Wave on back, just to balance the L/R lever feel at bite. The cons I see from Galfer's product page is that it'll wear pads faster (I burn rear pads faster regardless), and that they aren't as consistent with heat (I'm doing 2-3 min descents usually so I doubt that heat will really be an issue).
what pads are you using? & what brakes? I dont really have the 'fast wear' with the galfer purple ebike pads on waves.
I need help with choosing rotors. I currently run 223mm Trickstuff DH rotors F/R with Power+ pads. Under moderate to heavy braking they make the turkey...
I need help with choosing rotors. I currently run 223mm Trickstuff DH rotors F/R with Power+ pads. Under moderate to heavy braking they make the turkey gobble/warbling sound. Also when coasting down without pulling the brakes they make the awful ringing noise. I think this is mainly due to the 6 spoke design making the rotor quite flimsy in that regard.
My criteria for a rotor:
-223mm (I have +23mm Trickstuff adapters and I'm not going to buy new ones)
-Either Centerlock compatible or 6-bolt with the actual 6-bolt mounting part being under 2.2mm (I have centerlock hubs and DT Swiss centerlock adapters are rated for 2.2mm thick rotor mounting surface)
I'm interested in the Galfer Sharks. They come in 223mm and centerlock. To all you who run the 223mm shark rotors, do they "ring"?'
Just saw a '24 Altitude C90 on marketplace with Maven calipers mated to XTR levers. Has anyone on here tried this??
i think there is a thread of MTBR about this. Mavens are sick, but 2 of my 3 sets had junk in the lines and played up with the wandering bite point... it was pumping up then suddenly move to the normal spot - they were bled/setup by 4 different people(3 shops and me) - did all the bits and pieces correctly etc - 3rd set is good. - both those 2 sets were refunded.
I've never seen so much crap come out of a brake set before
On the flip side, The mavens are so immense, its the only brakes ive had to change down rotors on.
Those of you who have run both Sharks and Waves, what do you think about this idea? I'm trying to balance left / right lever feel...
Those of you who have run both Sharks and Waves, what do you think about this idea? I'm trying to balance left / right lever feel. Both brakes a bled perfectly, fresh pads, etc. My right brake (across many brands / models) always feels a little bit softer at bite point, I suspect due to muscle imbalance L/R. I've already been running Sharks F/R and like them a lot, but reading the Galfer description it sounds like the Waves bite a little bit harder. So I was thinking of putting a Wave on back, just to balance the L/R lever feel at bite. The cons I see from Galfer's product page is that it'll wear pads faster (I burn rear pads faster regardless), and that they aren't as consistent with heat (I'm doing 2-3 min descents usually so I doubt that heat will really be an issue).
Rear brake has almost always little more flex to it due to hose length, what you need is leverage adjustment and/or bite point adjustment.
Those of you who have run both Sharks and Waves, what do you think about this idea? I'm trying to balance left / right lever feel...
Those of you who have run both Sharks and Waves, what do you think about this idea? I'm trying to balance left / right lever feel. Both brakes a bled perfectly, fresh pads, etc. My right brake (across many brands / models) always feels a little bit softer at bite point, I suspect due to muscle imbalance L/R. I've already been running Sharks F/R and like them a lot, but reading the Galfer description it sounds like the Waves bite a little bit harder. So I was thinking of putting a Wave on back, just to balance the L/R lever feel at bite. The cons I see from Galfer's product page is that it'll wear pads faster (I burn rear pads faster regardless), and that they aren't as consistent with heat (I'm doing 2-3 min descents usually so I doubt that heat will really be an issue).
Yeah, I'm running Mavens on one bike so the Contact Adjust works like that and solves the problem. Full in on the adjuster makes the leverage higher / lever feel softer, so I'm running the front all the way in, and the rear ~6 clicks out from full in. I was wondering if I could use mismatched rotors to adjust it on brakes that don't have functional Contact Adjust (like Dominions).
But is the problem the lever feel or actually not biting enough? From what I can understand from your text it seems its a feel issue, in which case running a thicker rotor rear and thinner front would balance it out.
But is the problem the lever feel or actually not biting enough? From what I can understand from your text it seems its a feel issue...
But is the problem the lever feel or actually not biting enough? From what I can understand from your text it seems its a feel issue, in which case running a thicker rotor rear and thinner front would balance it out.
I'd say probably 80% lever feel, 20% actual bite. Most of the time when I'm just feathering the rear to bleed speed and I don't want to really lock it up, it's just the feel and probably doesn't really matter. In a few circumstances where I need to brake really hard for a short time to check speed before some feature, it feels like the rear lever pulls a bit closer to the bar (if the adjusters are set equal).
To be clear, plenty of power on tap here, both my Dominions and especially the Mavens. It's about making the left and right feel similar enough that I'm not noticing it when riding fast so that I can focus on other things.
Really I don't get why you should consider thicker rotor rear should change anything ?
Once your pads are settle, no matter what is the rotor width, they will have to do the exact same amount of travel (defined by the piston seal) to touch the rotor. The width of the rotor does not change anything.
But is the problem the lever feel or actually not biting enough? From what I can understand from your text it seems its a feel issue...
But is the problem the lever feel or actually not biting enough? From what I can understand from your text it seems its a feel issue, in which case running a thicker rotor rear and thinner front would balance it out.
I'd say probably 80% lever feel, 20% actual bite. Most of the time when I'm just feathering the rear to bleed speed and I don't want...
I'd say probably 80% lever feel, 20% actual bite. Most of the time when I'm just feathering the rear to bleed speed and I don't want to really lock it up, it's just the feel and probably doesn't really matter. In a few circumstances where I need to brake really hard for a short time to check speed before some feature, it feels like the rear lever pulls a bit closer to the bar (if the adjusters are set equal).
To be clear, plenty of power on tap here, both my Dominions and especially the Mavens. It's about making the left and right feel similar enough that I'm not noticing it when riding fast so that I can focus on other things.
the only way to fix is to make the front worse. This is the MTB way. I've always had to use the pad contact on the front brake to make it feel like the rear. It sucks but this is the easiest way to get F&R similar in feel.
I’m not 100% sure on the logic of this (if the longer hose makes a difference) but I often find my rear brake feel suffers much more IF the pistons are not all contacting the rotor at the same time. Once I ironed that out on my Hopes I found the front and rear much more similar, and the rear much more firm.
@Jonathon Simonetti had some great tips earlier in the thread (pg 5) on this.
Really I don't get why you should consider thicker rotor rear should change anything ?Once your pads are settle, no matter what is the rotor width...
Really I don't get why you should consider thicker rotor rear should change anything ?
Once your pads are settle, no matter what is the rotor width, they will have to do the exact same amount of travel (defined by the piston seal) to touch the rotor. The width of the rotor does not change anything.
Agreed, I think the reason why some of the SRAM pros are running Centerlines front instead of HS2s would be for the less bite. Boxxers are 200mm post mount so they can't downsize any further, only way to get less bite up front would be to have a less bite-y front rotor. HS2 felt noticeably more powerful than Centerline when they came out a few years ago.
@TSchafer yes that does make a huge difference. As part of my alignment process, after I get so that there's no rub, I very slowly squeeze the lever while watching to see if the rotor flexes in either direction.
How'd you go about bedding the pads and rotor in? Rudimentary q, but better asked than not. It looks like you got the brake way hot causing a bit of glazing. NBD, sand the rotor surface some, clean with iso. As for pads, I don't recommend using sandpaper on em but the edge of a CLEAN file to scuff up the surface. Reason being the adhesive used in the sandpaper may cause a contamination issue. Rotors are easy enough to remove potential contaminants, but pads aren't due to their porous nature.
Contamination or glazing is a frustrating process.
I recently spoke with MTX on a similar issue, but with brand new pads. To reset the setup, they told me to sand the pads until the glaze is gone. I used 120 grit paper and not much material was taken off. No need for cleaning agent on them, just blow the material off. They recommended acetone on the rotors to clean them. You could also lightly sand the rotors then acetone again.
I never ended up getting the old one working as I wanted. It would fade at the 80-100% power range, especially when cold. MTX were great to work with though and sent me a new set of pads that are now working flawlessly. Its hard to say why my first set didn't work, maybe the bedding process, maybe some contamination, but they didn't care . Highly recommended company. This is the first pads I had had issues with having over a dozen used.
After resetting, use this bedding process. I found take your time on the bedding process. My theory is no stoppies until you've rode them for a couple rides and they are working well at all temps. And no water on the bedding process. I had read that with others doing that to ease the process, but maybe that gave me a bedding issue.
https://support.mtxbraking.com/hc/en-us/articles/7069044211348-How-do-I…!
I once had a pair of Hope pads do exactly this - I was never able to figure out the source of the contamination or what went wrong in the first place, but I lost pretty much all braking friction with a fully glazed pad and that was all there was to it. Nothing I did could bring that set-up back. Fresh pair of pads solved the problem...
Maybe sometimes the pad compound just gets messed up from the factory, and "bleeds" resin under extreme heat or something.
I had a similar problem with MTX gold pads a couple months back on my XT/ZEE setup. Both pads would bed in well, then I'd a few minutes into a descent and immediately glaze the pads. I tried cleaning/sanding/rebedding 4 times and finally gave up. Contacted MTX and received friendly customer service but the guy couldn't give me an exact answer to my problem. The real solution was buying a set of T4 V4's lol.
alot of braking things from wandering bite point & 'lever to far out' to fiddly setups would be solved buying t4v4 👌
I need help with choosing rotors. I currently run 223mm Trickstuff DH rotors F/R with Power+ pads. Under moderate to heavy braking they make the turkey gobble/warbling sound. Also when coasting down without pulling the brakes they make the awful ringing noise. I think this is mainly due to the 6 spoke design making the rotor quite flimsy in that regard.
My criteria for a rotor:
-223mm (I have +23mm Trickstuff adapters and I'm not going to buy new ones)
-Either Centerlock compatible or 6-bolt with the actual 6-bolt mounting part being under 2.2mm (I have centerlock hubs and DT Swiss centerlock adapters are rated for 2.2mm thick rotor mounting surface)
I'm interested in the Galfer Sharks. They come in 223mm and centerlock. To all you who run the 223mm shark rotors, do they "ring"?'
To clarify, this is what I'm talking about:
https://www.reddit.com/r/bikewrench/comments/wpyd8b/cannot_track_down_t…
My Sharks actually came slightly warped but I suspect that was postage rather than Galfer themselves since my Waves arrived perfect. Easy to straighten them back though and they've been perfect since then. Quieter than the Waves, slightly less aggressive feeling, but otherwise nothing to say really - they work as they should
Ring? That's a video about a dude who can't align his caliper properly and has some serious issues with his bike otherwise too.
But, my sharks are flawless no "ringing".
That was just the first video I found that sounded similar. Mine make the exact same noise but my calipers are aligned properly.
some rotors, like shimano's terrible rt66 220 rotors vibrate & flex ALOT
aligned and straight rotors with any quality hub, The rotors will shake and vibrate so much they rub on the CALIPER when at speed.
these 220 rt66 rotors are also rubbish in performance, There is almost no stopping power difference between a 203 and rt66 220.... swapped out that rotor for a hs2 220 and it was soooo much better(i confirmed this by buying several rt66 220 when on spec) lucky they were cheap or id be pissed.
Those of you who have run both Sharks and Waves, what do you think about this idea? I'm trying to balance left / right lever feel. Both brakes a bled perfectly, fresh pads, etc. My right brake (across many brands / models) always feels a little bit softer at bite point, I suspect due to muscle imbalance L/R. I've already been running Sharks F/R and like them a lot, but reading the Galfer description it sounds like the Waves bite a little bit harder. So I was thinking of putting a Wave on back, just to balance the L/R lever feel at bite. The cons I see from Galfer's product page is that it'll wear pads faster (I burn rear pads faster regardless), and that they aren't as consistent with heat (I'm doing 2-3 min descents usually so I doubt that heat will really be an issue).
what pads are you using? & what brakes?
I dont really have the 'fast wear' with the galfer purple ebike pads on waves.
I use wave F/R or F with shark rear.
Just saw a '24 Altitude C90 on marketplace with Maven calipers mated to XTR levers. Has anyone on here tried this??
that's interesting, anyone else on Trickstuff DH rotors and or the Ultra Light ones? not stiff enough?
i think there is a thread of MTBR about this.
Mavens are sick, but 2 of my 3 sets had junk in the lines and played up with the wandering bite point... it was pumping up then suddenly move to the normal spot - they were bled/setup by 4 different people(3 shops and me) - did all the bits and pieces correctly etc - 3rd set is good.
- both those 2 sets were refunded.
I've never seen so much crap come out of a brake set before
On the flip side, The mavens are so immense, its the only brakes ive had to change down rotors on.
Rear brake has almost always little more flex to it due to hose length, what you need is leverage adjustment and/or bite point adjustment.
https://www.instagram.com/reel/C_vEpDOizxQ/
Yeah, I'm running Mavens on one bike so the Contact Adjust works like that and solves the problem. Full in on the adjuster makes the leverage higher / lever feel softer, so I'm running the front all the way in, and the rear ~6 clicks out from full in. I was wondering if I could use mismatched rotors to adjust it on brakes that don't have functional Contact Adjust (like Dominions).
But is the problem the lever feel or actually not biting enough? From what I can understand from your text it seems its a feel issue, in which case running a thicker rotor rear and thinner front would balance it out.
I'd say probably 80% lever feel, 20% actual bite. Most of the time when I'm just feathering the rear to bleed speed and I don't want to really lock it up, it's just the feel and probably doesn't really matter. In a few circumstances where I need to brake really hard for a short time to check speed before some feature, it feels like the rear lever pulls a bit closer to the bar (if the adjusters are set equal).
To be clear, plenty of power on tap here, both my Dominions and especially the Mavens. It's about making the left and right feel similar enough that I'm not noticing it when riding fast so that I can focus on other things.
Really I don't get why you should consider thicker rotor rear should change anything ?
Once your pads are settle, no matter what is the rotor width, they will have to do the exact same amount of travel (defined by the piston seal) to touch the rotor. The width of the rotor does not change anything.
the only way to fix is to make the front worse. This is the MTB way. I've always had to use the pad contact on the front brake to make it feel like the rear. It sucks but this is the easiest way to get F&R similar in feel.
I’m not 100% sure on the logic of this (if the longer hose makes a difference) but I often find my rear brake feel suffers much more IF the pistons are not all contacting the rotor at the same time. Once I ironed that out on my Hopes I found the front and rear much more similar, and the rear much more firm.
@Jonathon Simonetti had some great tips earlier in the thread (pg 5) on this.
Agreed, I think the reason why some of the SRAM pros are running Centerlines front instead of HS2s would be for the less bite. Boxxers are 200mm post mount so they can't downsize any further, only way to get less bite up front would be to have a less bite-y front rotor. HS2 felt noticeably more powerful than Centerline when they came out a few years ago.
@TSchafer yes that does make a huge difference. As part of my alignment process, after I get so that there's no rub, I very slowly squeeze the lever while watching to see if the rotor flexes in either direction.
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