Nerding out on Brakes shall we? Not another tech deraliment

8/5/2025 5:28am
Wacky idea:As we all know, shimano brakes get more snappy and powerful the further you adjust the lever away from the bars. I guess the lever...

Wacky idea:

As we all know, shimano brakes get more snappy and powerful the further you adjust the lever away from the bars. I guess the lever adjust changes the leverage ratio as well. 

It would be sweet if you could have the feeling you get with the levers far from the bars but actually have the lever nice and close to the bars. Maybe via a different pivot in the lever or by doing a really silly mod and filing down the bracing post and somehow changing the clamp angle to allow the lever to be angled in. 

Interesting as I run my levers/bite point relatively far away from the bar. I wonder how my dominions a4 will hold up against my shigura and complete shimanos. Didn't come to riding the Dominions apart from braking them in a bit.

1
willknisley
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Provo, UT US
8/10/2025 12:21pm Edited Date/Time 8/10/2025 12:22pm

Has anyone gotten their hands on the new hope evo gr4s yet? Seems like they’re back ordered everywhere.

Nobble
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Lakewood, CO US
8/10/2025 12:25pm

Has anyone gotten their hands on the new hope evo gr4s yet? Seems like they’re back ordered everywhere.

Don’t they launch in September?

1
willknisley
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Provo, UT US
8/10/2025 12:34pm

Has anyone gotten their hands on the new hope evo gr4s yet? Seems like they’re back ordered everywhere.

Nobble wrote:

Don’t they launch in September?

Ah didn’t see that before but looks like that’s correct so I guess not

Evil96
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Portogruaro, VE IT
8/10/2025 12:39pm

Has anyone gotten their hands on the new hope evo gr4s yet? Seems like they’re back ordered everywhere.

Nobble wrote:

Don’t they launch in September?

Ah didn’t see that before but looks like that’s correct so I guess not

It’s In like every single article about them “ from 1st of September 2025”

1
NHtoWA421
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Location
Bremerton, WA US
8/26/2025 7:19pm

Recently picked up the Hayes dominion to try, only to find out I have the dreaded pad rattle. I stretched the retainer clip out to an uncomfortable amount and still have a terrible rattle. What are some other tricks people have done? Shrink wrap around the pin didn’t fit (wouldn’t fit through the caliper hole) 

8/26/2025 8:38pm
NHtoWA421 wrote:
Recently picked up the Hayes dominion to try, only to find out I have the dreaded pad rattle. I stretched the retainer clip out to an...

Recently picked up the Hayes dominion to try, only to find out I have the dreaded pad rattle. I stretched the retainer clip out to an uncomfortable amount and still have a terrible rattle. What are some other tricks people have done? Shrink wrap around the pin didn’t fit (wouldn’t fit through the caliper hole) 

Just wait is my tip, the pads will generate enough dust they get stuck to the pistons in time. Every time I get new pads or give the brakes a good clean and remove the dust I get the rattle again, but it goes away in a week naturally.

A piece of tap over the top of the caliper touching the pads and springs will stop it, but it eventually melts from the heat. 

Because of the way the kingpin (pad retention pin) is designed you can't wrap the middle portion to stop the pad movement, which is where the noise is coming from mostly

1
JVP
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Location
Seattle, WA US
8/26/2025 8:41pm
NHtoWA421 wrote:
Recently picked up the Hayes dominion to try, only to find out I have the dreaded pad rattle. I stretched the retainer clip out to an...

Recently picked up the Hayes dominion to try, only to find out I have the dreaded pad rattle. I stretched the retainer clip out to an uncomfortable amount and still have a terrible rattle. What are some other tricks people have done? Shrink wrap around the pin didn’t fit (wouldn’t fit through the caliper hole) 

Stretch the spring more - but the key is stretching it open right at the base where the two halves connect. Need to do it with needle nose pliers.

I'm neurotic about quiet bikes and never had them rattle over many, many sets of pads after doing this.

1
DServy
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Jackson, WY US
8/27/2025 7:29am

Has anyone had any luck lever bleeding mavens with just the syringe? I feel like I've tried in the past and it's only made things worse. I was hoping to avoid a full bleed because I am lazy. 

ebruner
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Location
Tustin, CA US
8/27/2025 8:43am
DServy wrote:
Has anyone had any luck lever bleeding mavens with just the syringe? I feel like I've tried in the past and it's only made things worse...

Has anyone had any luck lever bleeding mavens with just the syringe? I feel like I've tried in the past and it's only made things worse. I was hoping to avoid a full bleed because I am lazy. 

Yes, but it involves using a funnel on the lever side.  I essentially bleed maven's like you'd bleed a car.  I put the funnel in the lever side and fill it, I think put a syringe on the bleeding edge port 1/3 full.  I put one hand on the bleeding edge port wing nut and another hand on the lever blade.  I pump the brake lever 3-5 times and then hold it tight.  While holding the lever I loosen the bleeding edge wing nut, allow the master to push fluid into the syringe and then close the bleeding edge port and then let go of the brake lever.  

The one thing you have to manage with this approach is any fluid that may be trapped in the lever prior to you starting the bleed process.  I find that that it's best to do a quick procedure of pulling VERY SLIGHT vacuum on the caliper bleeding edge syringe to pull any bubbles out of the caliper that are low lying fruit, and then push a small amount of fluid upwards to the lever/funnel.  I do not push much, as I do not want to introduce fluid that has contaminates from the caliper side all the way up into the lever.  I only push enough to get any air that is in the lever assembly out and into the funnel.  

Lastly, I wind the reach adjusters out super far to maximize leverage of the lever over the system so I can push as much fluid into the syringe with each bleeding cycle as possible.  I also usually start the process by hitting the caliper, line and lever assembly with an off brand theragun massager.  I picked this trick up from my LBS... seriously, it's worth spending 20 bucks on amazon for one of these specifically to bleed brakes, shocks and other items as it vibrates the air bubbles to the extreme ends of the system so you can eject them.  The other nice thing about the funnel is that you can finish by rotating the lever assembly down and flicking the lever, as well as winding in the contact point and do the same thing.  I do this usually once in the middle of my bleed process, and then finish with this to ensure I don't have air trapped in the lever.  

3
8/27/2025 9:18am
DServy wrote:
Has anyone had any luck lever bleeding mavens with just the syringe? I feel like I've tried in the past and it's only made things worse...

Has anyone had any luck lever bleeding mavens with just the syringe? I feel like I've tried in the past and it's only made things worse. I was hoping to avoid a full bleed because I am lazy. 

I've seemed to have good luck with it. Are you referring to using a syringe for ONLY a lever bleed? 

1
DServy
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Location
Jackson, WY US
8/27/2025 9:30am
DServy wrote:
Has anyone had any luck lever bleeding mavens with just the syringe? I feel like I've tried in the past and it's only made things worse...

Has anyone had any luck lever bleeding mavens with just the syringe? I feel like I've tried in the past and it's only made things worse. I was hoping to avoid a full bleed because I am lazy. 

I've seemed to have good luck with it. Are you referring to using a syringe for ONLY a lever bleed? 

yeah, I've tried using some Pinner bleed cups and do the lever bleeds like I've done with shimano brakes and it did not go well. I feel like I've only had success with full bleeds. Wanted to see if folks are having some success with lever bleed with syringes and how they are doing it. 

1
8/27/2025 9:51am
DServy wrote:
yeah, I've tried using some Pinner bleed cups and do the lever bleeds like I've done with shimano brakes and it did not go well. I...

yeah, I've tried using some Pinner bleed cups and do the lever bleeds like I've done with shimano brakes and it did not go well. I feel like I've only had success with full bleeds. Wanted to see if folks are having some success with lever bleed with syringes and how they are doing it. 

I added the zip tie lever trick to my Maven bleed process with good effect. In doing that I'm only bleeding the lever with the syringe by pulling a slight vacuum/flicking the lever, pressuring the system then closing it off. Hopefuly that helps. 

2
TEAMROBOT
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8/27/2025 12:02pm
I added the zip tie lever trick to my Maven bleed process with good effect. In doing that I'm only bleeding the lever with the syringe by...

I added the zip tie lever trick to my Maven bleed process with good effect. In doing that I'm only bleeding the lever with the syringe by pulling a slight vacuum/flicking the lever, pressuring the system then closing it off. Hopefuly that helps. 

I've been using the Pinner cup and SRAM adapter on my Mavens, and using the overnight zip tie lever trick has helped a lot. But I also appreciated the suggestion above to do a car brake bleed. I might try that next time I have to do a full bleed. Mavens are really hard to get all the air bubbles out of.

2
8/27/2025 12:16pm
TEAMROBOT wrote:
I've been using the Pinner cup and SRAM adapter on my Mavens, and using the overnight zip tie lever trick has helped a lot. But I...

I've been using the Pinner cup and SRAM adapter on my Mavens, and using the overnight zip tie lever trick has helped a lot. But I also appreciated the suggestion above to do a car brake bleed. I might try that next time I have to do a full bleed. Mavens are really hard to get all the air bubbles out of.

A few days ago I installed an internally routed rear brake on a frame I'm building up that didn't have handlebars/fork installed yet... Out of necessity I attached the lever to handlebars that I then stuck vertically into the head tube. Call it an even mixture of laziness and ingenuity. What this did was place the bleed hole with the syringe attached at the absolute highest point of the system. Logic would say that should give me the best chance to get all of the air out of the pesky lever reservoir. We'll see if dumb luck was helpful!
1
Evil96
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Portogruaro, VE IT
8/27/2025 12:29pm
I added the zip tie lever trick to my Maven bleed process with good effect. In doing that I'm only bleeding the lever with the syringe by...

I added the zip tie lever trick to my Maven bleed process with good effect. In doing that I'm only bleeding the lever with the syringe by pulling a slight vacuum/flicking the lever, pressuring the system then closing it off. Hopefuly that helps. 

TEAMROBOT wrote:
I've been using the Pinner cup and SRAM adapter on my Mavens, and using the overnight zip tie lever trick has helped a lot. But I...

I've been using the Pinner cup and SRAM adapter on my Mavens, and using the overnight zip tie lever trick has helped a lot. But I also appreciated the suggestion above to do a car brake bleed. I might try that next time I have to do a full bleed. Mavens are really hard to get all the air bubbles out of.

i found the 2 syringes Push only or very light vacuum + working those pistons in and out many times work pretty great, there's so much air always trapped behind the pistons, also i bled a couple with the Bionol and found it way easier to bleed compared to the maxima oil that seems to love air and keeping it 

1
DServy
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Jackson, WY US
8/27/2025 12:33pm
I added the zip tie lever trick to my Maven bleed process with good effect. In doing that I'm only bleeding the lever with the syringe by...

I added the zip tie lever trick to my Maven bleed process with good effect. In doing that I'm only bleeding the lever with the syringe by pulling a slight vacuum/flicking the lever, pressuring the system then closing it off. Hopefuly that helps. 

TEAMROBOT wrote:
I've been using the Pinner cup and SRAM adapter on my Mavens, and using the overnight zip tie lever trick has helped a lot. But I...

I've been using the Pinner cup and SRAM adapter on my Mavens, and using the overnight zip tie lever trick has helped a lot. But I also appreciated the suggestion above to do a car brake bleed. I might try that next time I have to do a full bleed. Mavens are really hard to get all the air bubbles out of.

Are you putting in bleed blocks and winding the contact point out (away from the arrow) or just leaving it as is and slapping on the pinner cups. 

Nobble
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Lakewood, CO US
8/27/2025 1:55pm Edited Date/Time 8/27/2025 1:58pm

I am so frustrated with my Mavens, they seem impossible to get consistent.


I got one good bleed on them and then the bike sat for a few months over winter while I moved and it went to shit. Every other bleed/piston massage seems to only stave off the pump-up bite point for less than half a day of riding. I’ve even had two different shops work on them in addition to myself.


I really want them to work right because everything else is great but if Hope’s new GR4s have firmed up the bite point then I think I’m getting rid of the Mavens.


If anyone has suggestions other than “must be a bad bleed” or “try massaging the pistons”, I’m all ears.

2
TEAMROBOT
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8/27/2025 3:51pm Edited Date/Time 8/28/2025 11:29am
DServy wrote:
Are you putting in bleed blocks and winding the contact point out (away from the arrow) or just leaving it as is and slapping on the...

Are you putting in bleed blocks and winding the contact point out (away from the arrow) or just leaving it as is and slapping on the pinner cups. 

Both, depending on the day and how much effort I'm willing to put in.

If I'm really feeling like a go getter, I put the bike in a stand with both wheels off, tilted waaaaaaaay up with the rear axle near the ground, unbolt the rear caliper, and hang it from the frame (with a bleed block) so it's all uphill from the bottom of the caliper to the bleed port in the lever. God I hate internal hose routing. Then I leave the lever zip-tied overnight and bleed in the morning, combined with multiple rounds of piston massages. These bleeds tend to help a lot.

But I've also done quick and dirty lever bleeds where I just stick a pad spacer in between the pads and leave the caliper in place on the frame. These (predictably) tend to be less fruitful.

1
megastoke
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La Grande, OR US
8/28/2025 7:15am
TEAMROBOT wrote:
Both, depending on the day and how much effort I'm willing to put in.If I'm really feeling like a go getter, I put the bike in...

Both, depending on the day and how much effort I'm willing to put in.

If I'm really feeling like a go getter, I put the bike in a stand with both wheels off, tilted waaaaaaaay up with the rear axle near the ground, unbolt the rear caliper, and hang it from the frame (with a bleed block) so it's all uphill from the bottom of the caliper to the bleed port in the lever. God I hate internal hose routing. Then I leave the lever zip-tied overnight and bleed in the morning, combined with multiple rounds of piston massages. These bleeds tend to help a lot.

But I've also done quick and dirty lever bleeds where I just stick a pad spacer in between the pads and leave the caliper in place on the frame. These (predictably) tend to be less fruitful.

To the point of hating internal hose routing, anyone have a recommendation for the best available stick on cable guides? 

1
HexonJuan
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8/28/2025 9:55am

Y'all got me wondering about the Mavens and down a rabbit hole I went. Couple things stood out to me in the MC's architecture. 1. The diaphragm for the reservoir has a lotta 90deg angles. Fluids (of which air is one) don't like moving smoothly around right angles. This might be making a proper purge of the system difficult, whether by cup or syringe. 2. They use a single timing port hole to allow fluid passage between the MC bore and the res. Might this create a choke point that is in turn causing a slight bit of cavitation during use? With the larger caliper pistons, there's more fluid moving to n fro. Can that timing port allow it to move smoothly in all brake actuation scenarios? This of course leads to the compression and banjo fittings. Are their diameters large enough to allow for smooth fluid movement in all actuation scenarios?

3
yzedf
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Hebron, CT US
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8/28/2025 9:57am
megastoke wrote:

To the point of hating internal hose routing, anyone have a recommendation for the best available stick on cable guides? 

I’ve had good luck in the past with the Jagwire ones. They will bend to nearly flat without much issue if you need them to. 

1
Nobble
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Lakewood, CO US
8/28/2025 10:24am
HexonJuan wrote:
Y'all got me wondering about the Mavens and down a rabbit hole I went. Couple things stood out to me in the MC's architecture. 1. The...

Y'all got me wondering about the Mavens and down a rabbit hole I went. Couple things stood out to me in the MC's architecture. 1. The diaphragm for the reservoir has a lotta 90deg angles. Fluids (of which air is one) don't like moving smoothly around right angles. This might be making a proper purge of the system difficult, whether by cup or syringe. 2. They use a single timing port hole to allow fluid passage between the MC bore and the res. Might this create a choke point that is in turn causing a slight bit of cavitation during use? With the larger caliper pistons, there's more fluid moving to n fro. Can that timing port allow it to move smoothly in all brake actuation scenarios? This of course leads to the compression and banjo fittings. Are their diameters large enough to allow for smooth fluid movement in all actuation scenarios?

In all my messing with them, I’m pretty much convinced that the inconsistency comes from the caliper.


My personal theory is that something about the caliper causes the pads to roll back too slowly. It’s either the seal material is too soft, or there’s some sort of flow restriction. If you pull the lever multiple times quickly, you’re pulling the lever again before the pistons have retracted and that’s why they pump up.


I’ve been considering a couple of possible fixes to test:

1. Try to align the holes in the banjo bolt with the hole in the fitting for the hose. (This could explain why some people have zero issues with them, they just get lucky and all the holes line up nicely)

2. Try deburring, chamfering, or making the banjo bolt holes larger.

3. Try deburring or “porting” the transfer ports between the caliper halves. I’ve had to split the caliper a couple of times because I got a little impatient with my umpteenth piston massage and noticed that the ports looked kinda messy on the edges.

2
snowsnakes
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Location
Anchorage, AK US
8/28/2025 4:27pm

Anyone have issues with their Hope V4 pads rattling front-to-back in the caliper? The pads in my E4 calipers seem perfectly sized (T4 E4 and XCR E4), but there's some free play with the pads in the V4 allowing them to rock or rattle. I'm struggling to think of a solution besides a strip of mastic tape on either end of the caliper (which I think would melt?) 

bigbrett
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Salt Lake City, UT US
8/29/2025 1:32am
snowsnakes wrote:
Anyone have issues with their Hope V4 pads rattling front-to-back in the caliper? The pads in my E4 calipers seem perfectly sized (T4 E4 and XCR...

Anyone have issues with their Hope V4 pads rattling front-to-back in the caliper? The pads in my E4 calipers seem perfectly sized (T4 E4 and XCR E4), but there's some free play with the pads in the V4 allowing them to rock or rattle. I'm struggling to think of a solution besides a strip of mastic tape on either end of the caliper (which I think would melt?) 

Yes, and these better bolts after market pins retaining pins eliminated it for me. From their website: “For Hope V4 brake pad axles the center shaft has been machined larger than stock to eliminate pad rattle”

4
ballz
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Ouagadougou EH
8/29/2025 7:09am
snowsnakes wrote:
Anyone have issues with their Hope V4 pads rattling front-to-back in the caliper? The pads in my E4 calipers seem perfectly sized (T4 E4 and XCR...

Anyone have issues with their Hope V4 pads rattling front-to-back in the caliper? The pads in my E4 calipers seem perfectly sized (T4 E4 and XCR E4), but there's some free play with the pads in the V4 allowing them to rock or rattle. I'm struggling to think of a solution besides a strip of mastic tape on either end of the caliper (which I think would melt?) 

I used small strips of hockey tape on the edge/back of the pads and they seemed to work well, but I don't push my brakes to super high temperatures. You can also try to open the retaining springs absurdly wide.

1
HexonJuan
Posts
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6/10/2015
Location
WI US
8/29/2025 7:26am
HexonJuan wrote:
Y'all got me wondering about the Mavens and down a rabbit hole I went. Couple things stood out to me in the MC's architecture. 1. The...

Y'all got me wondering about the Mavens and down a rabbit hole I went. Couple things stood out to me in the MC's architecture. 1. The diaphragm for the reservoir has a lotta 90deg angles. Fluids (of which air is one) don't like moving smoothly around right angles. This might be making a proper purge of the system difficult, whether by cup or syringe. 2. They use a single timing port hole to allow fluid passage between the MC bore and the res. Might this create a choke point that is in turn causing a slight bit of cavitation during use? With the larger caliper pistons, there's more fluid moving to n fro. Can that timing port allow it to move smoothly in all brake actuation scenarios? This of course leads to the compression and banjo fittings. Are their diameters large enough to allow for smooth fluid movement in all actuation scenarios?

Nobble wrote:
In all my messing with them, I’m pretty much convinced that the inconsistency comes from the caliper.My personal theory is that something about the caliper causes...

In all my messing with them, I’m pretty much convinced that the inconsistency comes from the caliper.


My personal theory is that something about the caliper causes the pads to roll back too slowly. It’s either the seal material is too soft, or there’s some sort of flow restriction. If you pull the lever multiple times quickly, you’re pulling the lever again before the pistons have retracted and that’s why they pump up.


I’ve been considering a couple of possible fixes to test:

1. Try to align the holes in the banjo bolt with the hole in the fitting for the hose. (This could explain why some people have zero issues with them, they just get lucky and all the holes line up nicely)

2. Try deburring, chamfering, or making the banjo bolt holes larger.

3. Try deburring or “porting” the transfer ports between the caliper halves. I’ve had to split the caliper a couple of times because I got a little impatient with my umpteenth piston massage and noticed that the ports looked kinda messy on the edges.

Dig the idea of the banjo bolt. I haven't seen one for the Mavens yet, however I have improved performance on other brakes by cross drilling and dilating the ports. There's not a lot of material there to work with, so a smidge bigger is better than way bigger. Def worth a shot since banjo bolts are relatively cheap and inexpensive.

 

1
DServy
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238
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5/28/2015
Location
Jackson, WY US
8/29/2025 7:45am

Update on some Maven bleeding:

Tried the pinner cups/overnight bleed/dangling caliper with bleed blocks in on 3 sets of mavens and the improvement is dramatic. At this point I'm fairly convinced that the mineral oil formula that SRAM is using holds onto air a bit more than some other formulas (like magura/shimano), and that degassing the mineral oil is a very important step. 

Also, the more aggressive the piston massage the better. I've also noticed that I need to do it a 3-4 times for things to really improve, and I repeat the process until the pistons move evenly and very freely (both coming out and being pushed back by a spacer). The manual does say give'r the beans on the piston massage and I really think they mean it. 

6
TEAMROBOT
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Los Angeles, CA US
Fantasy
8/29/2025 7:52am
DServy wrote:
Update on some Maven bleeding:Tried the pinner cups/overnight bleed/dangling caliper with bleed blocks in on 3 sets of mavens and the improvement is dramatic. At this...

Update on some Maven bleeding:

Tried the pinner cups/overnight bleed/dangling caliper with bleed blocks in on 3 sets of mavens and the improvement is dramatic. At this point I'm fairly convinced that the mineral oil formula that SRAM is using holds onto air a bit more than some other formulas (like magura/shimano), and that degassing the mineral oil is a very important step. 

Also, the more aggressive the piston massage the better. I've also noticed that I need to do it a 3-4 times for things to really improve, and I repeat the process until the pistons move evenly and very freely (both coming out and being pushed back by a spacer). The manual does say give'r the beans on the piston massage and I really think they mean it. 

Nice! That's awesome to hear. Thanks for reporting back.

8/29/2025 10:09am
I watch the pistons advance when I'm massaging and if one is fast I'll hold it back with a flat head screwdriver until the others catch up or if it's slow work that single piston a few times. When new this is more noticeable.
 
Also when new I massage them many times, without focusing too much on force every cycle but just to get them moving in and out. I'm convinced there's some break in period on the seals.
1

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