Nerding out on Brakes shall we? Not another tech deraliment

Jakub_G
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5/15/2025 8:55am
Evil96 wrote:
Question for you all nerdsBack from when I was on Maguras I never had to think about this rotor size and spacing as it was perfect...

Question for you all nerds

Back from when I was on Maguras I never had to think about this rotor size and spacing as it was perfect pm180 frame/fork pm +40 or 23 adapter and run 220/203 pads were biting perfect at the top of the rotor, great match.

Switched to Hope, running the same bike and fork, 203 rotors so the H adapter +23mm

Noticed the pads were biting quite low and on their “tech book” Hope states there should be 0.5 1mm max of un “bitten” rotor.

While it seems a bit odd I measured mines and I was 1.76mm off, and on another bike I installed some 200 rotors today It was sitting so low the rotor was actually touching the top of the caliper with the proper +20 adapter, had to move it to +23 to have the pads at the correct height.

Now back on my bike, I put some 1.47 washers under the caliper and now the pads and rotors are a perfect match,

So I’m wondering where’s the issue here?

Hope caliper sitting too low?

I’d love to run everything flush with no washers especially since they don’t have any proper facing or anyrhing, thankfully these brakes are easy to align but ideally I’d have the calipers flush on the adapters and nothing else. 

IMG 9565.jpeg?VersionId=BtqtTtIMG 9568

As long as the top edge of rotor is not below the top edge of the pad it's fine,your last picture looks bang on the money to be honest.

2
AndehM
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El Granada, CA US
5/15/2025 9:06am
Evil96 wrote:
Question for you all nerdsBack from when I was on Maguras I never had to think about this rotor size and spacing as it was perfect...

Question for you all nerds

Back from when I was on Maguras I never had to think about this rotor size and spacing as it was perfect pm180 frame/fork pm +40 or 23 adapter and run 220/203 pads were biting perfect at the top of the rotor, great match.

Switched to Hope, running the same bike and fork, 203 rotors so the H adapter +23mm

Noticed the pads were biting quite low and on their “tech book” Hope states there should be 0.5 1mm max of un “bitten” rotor.

While it seems a bit odd I measured mines and I was 1.76mm off, and on another bike I installed some 200 rotors today It was sitting so low the rotor was actually touching the top of the caliper with the proper +20 adapter, had to move it to +23 to have the pads at the correct height.

Now back on my bike, I put some 1.47 washers under the caliper and now the pads and rotors are a perfect match,

So I’m wondering where’s the issue here?

Hope caliper sitting too low?

I’d love to run everything flush with no washers especially since they don’t have any proper facing or anyrhing, thankfully these brakes are easy to align but ideally I’d have the calipers flush on the adapters and nothing else. 

IMG 9565.jpeg?VersionId=BtqtTtIMG 9568

It looks to me like with the extra spacers you're definitely too high.  Look at the center of the pistons vs. center of the rotor radius.  Center of your pistons right now is right on the 3rd row of holes (in the 4-hole pattern), instead of in between the 2nd & 3rd rows of holes.

Eae903
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5/15/2025 12:50pm
Eae903 wrote:

I mean, both of them have contact point / free stroke adjustments, are we measuring at the extremes? 

Jakub_G wrote:

Only one of them is meant to be adjusted and actually does good job at that. The other one, well, not so much.

For some reason, I assume you mean the codes adjustment being the one that works but I've had good luck with both. 

brash
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5/15/2025 3:14pm

talk to me about facing brake mounts, imagine I know nothing about it (which is true lol)

can it be done with a file and a calibrated eyeball or do you need special tools?

1
ballz
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5/15/2025 3:55pm
brash wrote:
talk to me about facing brake mounts, imagine I know nothing about it (which is true lol)can it be done with a file and a calibrated...

talk to me about facing brake mounts, imagine I know nothing about it (which is true lol)

can it be done with a file and a calibrated eyeball or do you need special tools?

Yes.

1
Eae903
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5/15/2025 5:43pm
brash wrote:
talk to me about facing brake mounts, imagine I know nothing about it (which is true lol)can it be done with a file and a calibrated...

talk to me about facing brake mounts, imagine I know nothing about it (which is true lol)

can it be done with a file and a calibrated eyeball or do you need special tools?

ballz wrote:

Yes.

Facing is best done with special tools that ensure that the mount is level when you're done, but if you're really careful and don't mind ruining the mounts if you mess up, you could try to do it with a file. 

5
29
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5/15/2025 10:47pm

Isn’t the whole point of facing to get a completely level surface in a 90° angle to the the thread?


Any time I filed something I couldn’t get it completely flat without rounding off any corners, and I doubt you could get it at the right angle by just eyeballing. 

3
Primoz
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5/15/2025 10:52pm
29 wrote:
Isn’t the whole point of facing to get a completely level surface in a 90° angle to the the thread?Any time I filed something I couldn’t...

Isn’t the whole point of facing to get a completely level surface in a 90° angle to the the thread?


Any time I filed something I couldn’t get it completely flat without rounding off any corners, and I doubt you could get it at the right angle by just eyeballing. 

Correct. 

1
brash
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5/16/2025 12:36am
29 wrote:
Isn’t the whole point of facing to get a completely level surface in a 90° angle to the the thread?Any time I filed something I couldn’t...

Isn’t the whole point of facing to get a completely level surface in a 90° angle to the the thread?


Any time I filed something I couldn’t get it completely flat without rounding off any corners, and I doubt you could get it at the right angle by just eyeballing. 

thats why I asked the question before I start hacking at my 38's with a file from 1845 I inherited.

2
mannebask
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5/16/2025 12:50am

Ok. So after being on Shimano brakes (SLX, XT 4-pots and Saints) for an eternity I picked up a bike with Hayes Dominion A4. First impressions are that these are some nice feeling brakes and nice action and good stopping power, but no wow factor for me, at least for first impressions. I will try some other pads and also run them in the bikepark for more extensive testing for sure. 

2
Primoz
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5/16/2025 4:07am Edited Date/Time 5/16/2025 4:08am

No wow factor in the parking lot or actually using them to stop going down a trail? Shimanos are VERY wow in the parking lot because of their on-off characteristic.

@brash yeah, don't...

2
5/16/2025 5:06am Edited Date/Time 5/16/2025 5:12am
brash wrote:
talk to me about facing brake mounts, imagine I know nothing about it (which is true lol)can it be done with a file and a calibrated...

talk to me about facing brake mounts, imagine I know nothing about it (which is true lol)

can it be done with a file and a calibrated eyeball or do you need special tools?

It can be done with a file, but 99% of the population lacks the skill to do that properly. The end result would most likely be neither flat nor perpendicular to the mounting bolts. Both issues would make brake setup more difficult. 

I did my fork with a fine file, but I build prototype firearms parts for a living so I have above average skill with fitting parts with a file. 

3
boozed
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5/16/2025 5:33am

From my position of more or less complete ignorance on the matter, I thought the intention of facing the brake mounts was to get them to be perpendicular to the brake disc, not the mounting bolt axes?

3
Primoz
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5/16/2025 5:44am Edited Date/Time 5/16/2025 5:45am

Ideally one is the same as the other anyway... But yeah, the intention is for the face to be perpendicular to the wheel axle (which is how the tools look like as well). If the bolt is not perpendicular you can still use a cup and cone washer to adapt to it, but if the mounting face is not perpendicular, the caliper (or adapter) will not sit perpendicular either. 

2
mannebask
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5/16/2025 6:49am
Primoz wrote:
No wow factor in the parking lot or actually using them to stop going down a trail? Shimanos are VERY wow in the parking lot because...

No wow factor in the parking lot or actually using them to stop going down a trail? Shimanos are VERY wow in the parking lot because of their on-off characteristic.

@brash yeah, don't...

I took them down a few of my steepest gnarliest trails in my local woods. Almost rammed a tree when i pulled the brakes and expecting the bite point to come real fast. 

Anyhow, first test means nothing. I'm still sure they're great so I will give it more time. 

1
Eae903
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5/16/2025 7:01am

Keep in mind that when you are facing the mounts, you are removing material. Hopefully it's not too much but you might need to modify your spacers afterwards to make sure the pads contact correctly, like those hope brakes from before. 

3
mtbjoe
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5/19/2025 2:29am

Anyone use the hayes dominion hoses on hope tech v4? Found some for practically free and they are super stiff and beefy. ID is 2.5mm vs 2.1mm for the standard hoses. The standard hope barb seems to be too small but would it work with an olive compressing? Any idea on how this would change the character of the brakes? 

1
Evil96
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5/19/2025 2:37am
mtbjoe wrote:
Anyone use the hayes dominion hoses on hope tech v4? Found some for practically free and they are super stiff and beefy. ID is 2.5mm vs...

Anyone use the hayes dominion hoses on hope tech v4? Found some for practically free and they are super stiff and beefy. ID is 2.5mm vs 2.1mm for the standard hoses. The standard hope barb seems to be too small but would it work with an olive compressing? Any idea on how this would change the character of the brakes? 

considering the very lowe price of the braided hoses, why not going that direction?

1
mtbjoe
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5/19/2025 3:05am
mtbjoe wrote:
Anyone use the hayes dominion hoses on hope tech v4? Found some for practically free and they are super stiff and beefy. ID is 2.5mm vs...

Anyone use the hayes dominion hoses on hope tech v4? Found some for practically free and they are super stiff and beefy. ID is 2.5mm vs 2.1mm for the standard hoses. The standard hope barb seems to be too small but would it work with an olive compressing? Any idea on how this would change the character of the brakes? 

Evil96 wrote:

considering the very lowe price of the braided hoses, why not going that direction?

I have the hayes hoses in hand, not the braided

4
Teknik
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5/20/2025 11:12am
Evil96 wrote:

considering the very lowe price of the braided hoses, why not going that direction?

How do we actually if the braided hose makes the brakes any better? I’ve always thought that it only protects the outer shell which is not so critical in cycling. I assume all hydraulic brake hose have hard plastic innertube that withstands the pressure and does the magic.

2
Evil96
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5/20/2025 12:21pm
Evil96 wrote:

considering the very lowe price of the braided hoses, why not going that direction?

Teknik wrote:
How do we actually if the braided hose makes the brakes any better? I’ve always thought that it only protects the outer shell which is not...

How do we actually if the braided hose makes the brakes any better? I’ve always thought that it only protects the outer shell which is not so critical in cycling. I assume all hydraulic brake hose have hard plastic innertube that withstands the pressure and does the magic.

Not sure 100%, Trickstuff claims their Beta Kevlar hoses to be rated for 860bar or similar while the Goodridge Braided to be rated for 1360bar ( might be 1340 and 840 can’t remember the exact number but the difference is still huge )

Therefore a stiffer line should provide a sharper bite point and more consistent feel given there’s no room for expansion.

The plastic hose inside will expand its what’s around that might prevent it.

This is probably the reason why Pros use Shimano hoses on TRP as they find the TRP not stiff enough

2
ebruner
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5/20/2025 1:29pm Edited Date/Time 5/20/2025 1:30pm

@AndehM & @FaahkEet had inquired about aftermarket levers on sram brakes in the tech rumors thread.  I am moving the response to that over here.  I have freedom coast levers on my TRP DHR Evo's and I have them on a set of maven bronze.  I also have a set of Oak Components levers that I previously had on a set of Code RSC and now on a set of Maven Ultimate.  

I quite like the levers on the DHR Evos... I would consider aftermarket levers on those brakes a must.  That being said, it took me a bit to adjust to running my finger just inside the lever hook.  From years of riding stock sram levers, I had learned to put my finger directly on the hook, which can be a slight bit less comfortable with the freedom coast machining on the hook for some reason.

I say this because that is my impression on the difference between running the freedom coast and the oak components levers on maven brakes as well.  Both are good from an ergonomics perspective... but the oak components have a slightly more comfortable hook then the freedom coast do, so it makes it a bit easier to run the lever position on the bars, such that your finger is resting within the hook when in use.  

One thing that I have found as consistent with the aftermarket levers... is that the reach adjust is not as sufficient with the different lever shape.  For whatever reason, I cannot setup the reach adjust so that the lever bottoms out on the grip when you wind them all the way counter clockwise (lever's in).  This is mostly fine if you have reach adjust, but not fine if you are on base/bronze level brakes, or are the kind of person that does not want to use reach adjust because of the swing link cam profile.  

That being said, when setup properly, the maven bronze that I have them on (on my 25' santacruz bullit) ends up with the last little bit of lever throw about 1/8" from the bar at full lock.  It feels a bit like I would like them to go just a bit further, that way I could adjust them out to exactly where I want them.  Overall, I'd equate it to having to run rebound or compression all the way to one side of the adjuster, sure it feels good and that's the best setting that is available, but you're always wondering what if I could go a bit futher.  I'd likely end up back at the same place, but I still wonder.

Overall however, I do like the aftermarket lever feel.  I'd say that they are not as impactful to the feel/performance or perception of the brakes as it was on the codes, but it is a nice improvement and for sure the lever feels more solid, like there is less flex.  

PXL 20250520 192928560 0.jpg?VersionId=1Eg80k3

4
29
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5/20/2025 2:25pm

Have the oak levers on maven silvers. Can confirm, lever feels less flexy which translates to a bit more power. Not super noticeable, but it’s there. 

Mounting them was a bit of a hassle but definitely an upgrade from stock levers imo

2
7willmorris
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5/20/2025 2:41pm

Figure a lot of people here will find this interesting:

Basically he reduces the master cylinder diameter from 10 to 8mm which significantly increases hydraulic advantage. Also the brake comparison website he shows is such a good resource: https://brakes.ddzyne.nl Not sure how no one's found it yet.

I'm actually doing something kind of similar with a set of brakes currently. Picked up a set of sram db8 calipers for cheap and am running them with formula cura levers (coming from cura 2 calipers). This results in quite a bit less power because of the reduced hydraulic ratio (4.36 vs 5.22) but you do gain access to like an order of magnitude more aftermarket pad options and get more piston rollback (pad-rotor clearance). Not wanting to mess with modifying internal components so I'm currently getting a new set of lever blades machined that increases mechanical advantage from 7.1 to 8.5. This will boost the total advantage to slightly higher than DHR Evos, Cura 4s, or Tech 3 V4s. Here's my lever design for those interested:

Screenshot 2025-05-20 143017.png?VersionId=0ZtQ0MvxQ8pob4h4mAsScreenshot 2025-05-20 142937

In addition to increasing leverage it also reduces the tolerance between the lever blade and master cylinder body which significantly reduces the bushing play present in stock cura levers. I've got a previous version I'm currently running that reduces bushing play but has about the same leverage as the formula "feel control" levers in the highest leverage setting but allow the lever to be run much closer to the bar. I found the range of reach adjust on the formula levers to be too far out. Those are 3d printed out of titanium and look like this:

IMG 3333

IMG 3335.jpeg?VersionId=mxY9AyHJzEBpcaeCw

7
ardor
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5/20/2025 3:38pm
Figure a lot of people here will find this interesting:Basically he reduces the master cylinder diameter from 10 to 8mm which significantly increases hydraulic advantage. Also...

Figure a lot of people here will find this interesting:

Basically he reduces the master cylinder diameter from 10 to 8mm which significantly increases hydraulic advantage. Also the brake comparison website he shows is such a good resource: https://brakes.ddzyne.nl Not sure how no one's found it yet.

I'm actually doing something kind of similar with a set of brakes currently. Picked up a set of sram db8 calipers for cheap and am running them with formula cura levers (coming from cura 2 calipers). This results in quite a bit less power because of the reduced hydraulic ratio (4.36 vs 5.22) but you do gain access to like an order of magnitude more aftermarket pad options and get more piston rollback (pad-rotor clearance). Not wanting to mess with modifying internal components so I'm currently getting a new set of lever blades machined that increases mechanical advantage from 7.1 to 8.5. This will boost the total advantage to slightly higher than DHR Evos, Cura 4s, or Tech 3 V4s. Here's my lever design for those interested:

Screenshot 2025-05-20 143017.png?VersionId=0ZtQ0MvxQ8pob4h4mAsScreenshot 2025-05-20 142937

In addition to increasing leverage it also reduces the tolerance between the lever blade and master cylinder body which significantly reduces the bushing play present in stock cura levers. I've got a previous version I'm currently running that reduces bushing play but has about the same leverage as the formula "feel control" levers in the highest leverage setting but allow the lever to be run much closer to the bar. I found the range of reach adjust on the formula levers to be too far out. Those are 3d printed out of titanium and look like this:

IMG 3333

IMG 3335.jpeg?VersionId=mxY9AyHJzEBpcaeCw

That comparison site is great!

2
Evil96
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Portogruaro, VE IT
5/20/2025 3:53pm
Figure a lot of people here will find this interesting:Basically he reduces the master cylinder diameter from 10 to 8mm which significantly increases hydraulic advantage. Also...

Figure a lot of people here will find this interesting:

Basically he reduces the master cylinder diameter from 10 to 8mm which significantly increases hydraulic advantage. Also the brake comparison website he shows is such a good resource: https://brakes.ddzyne.nl Not sure how no one's found it yet.

I'm actually doing something kind of similar with a set of brakes currently. Picked up a set of sram db8 calipers for cheap and am running them with formula cura levers (coming from cura 2 calipers). This results in quite a bit less power because of the reduced hydraulic ratio (4.36 vs 5.22) but you do gain access to like an order of magnitude more aftermarket pad options and get more piston rollback (pad-rotor clearance). Not wanting to mess with modifying internal components so I'm currently getting a new set of lever blades machined that increases mechanical advantage from 7.1 to 8.5. This will boost the total advantage to slightly higher than DHR Evos, Cura 4s, or Tech 3 V4s. Here's my lever design for those interested:

Screenshot 2025-05-20 143017.png?VersionId=0ZtQ0MvxQ8pob4h4mAsScreenshot 2025-05-20 142937

In addition to increasing leverage it also reduces the tolerance between the lever blade and master cylinder body which significantly reduces the bushing play present in stock cura levers. I've got a previous version I'm currently running that reduces bushing play but has about the same leverage as the formula "feel control" levers in the highest leverage setting but allow the lever to be run much closer to the bar. I found the range of reach adjust on the formula levers to be too far out. Those are 3d printed out of titanium and look like this:

IMG 3333

IMG 3335.jpeg?VersionId=mxY9AyHJzEBpcaeCw

ardor wrote:

That comparison site is great!

Wish it was updated, it’s got old stuff and missing the newest, would be sick if it had all the new ones 

2
5/20/2025 8:03pm
Figure a lot of people here will find this interesting:Basically he reduces the master cylinder diameter from 10 to 8mm which significantly increases hydraulic advantage. Also...

Figure a lot of people here will find this interesting:

Basically he reduces the master cylinder diameter from 10 to 8mm which significantly increases hydraulic advantage. Also the brake comparison website he shows is such a good resource: https://brakes.ddzyne.nl Not sure how no one's found it yet.

I'm actually doing something kind of similar with a set of brakes currently. Picked up a set of sram db8 calipers for cheap and am running them with formula cura levers (coming from cura 2 calipers). This results in quite a bit less power because of the reduced hydraulic ratio (4.36 vs 5.22) but you do gain access to like an order of magnitude more aftermarket pad options and get more piston rollback (pad-rotor clearance). Not wanting to mess with modifying internal components so I'm currently getting a new set of lever blades machined that increases mechanical advantage from 7.1 to 8.5. This will boost the total advantage to slightly higher than DHR Evos, Cura 4s, or Tech 3 V4s. Here's my lever design for those interested:

Screenshot 2025-05-20 143017.png?VersionId=0ZtQ0MvxQ8pob4h4mAsScreenshot 2025-05-20 142937

In addition to increasing leverage it also reduces the tolerance between the lever blade and master cylinder body which significantly reduces the bushing play present in stock cura levers. I've got a previous version I'm currently running that reduces bushing play but has about the same leverage as the formula "feel control" levers in the highest leverage setting but allow the lever to be run much closer to the bar. I found the range of reach adjust on the formula levers to be too far out. Those are 3d printed out of titanium and look like this:

IMG 3333

IMG 3335.jpeg?VersionId=mxY9AyHJzEBpcaeCw

I’ll be honest, that big of a change in master cylinder diameter doesn’t sound wonderful. Comparing the distance you’d have to move the master cylinder to move the pads the same amount, it’s a 56% increase. That’s a lot of lever throw… one conclusion I’ve come to is that massive power and good lever feel aren’t really attainable without decreased pad retract. Swing link kind of gets you there but there’s a stiff portion of lever throw it has to move through. 

4
7willmorris
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Squamish CA
5/20/2025 9:58pm
Figure a lot of people here will find this interesting:Basically he reduces the master cylinder diameter from 10 to 8mm which significantly increases hydraulic advantage. Also...

Figure a lot of people here will find this interesting:

Basically he reduces the master cylinder diameter from 10 to 8mm which significantly increases hydraulic advantage. Also the brake comparison website he shows is such a good resource: https://brakes.ddzyne.nl Not sure how no one's found it yet.

I'm actually doing something kind of similar with a set of brakes currently. Picked up a set of sram db8 calipers for cheap and am running them with formula cura levers (coming from cura 2 calipers). This results in quite a bit less power because of the reduced hydraulic ratio (4.36 vs 5.22) but you do gain access to like an order of magnitude more aftermarket pad options and get more piston rollback (pad-rotor clearance). Not wanting to mess with modifying internal components so I'm currently getting a new set of lever blades machined that increases mechanical advantage from 7.1 to 8.5. This will boost the total advantage to slightly higher than DHR Evos, Cura 4s, or Tech 3 V4s. Here's my lever design for those interested:

Screenshot 2025-05-20 143017.png?VersionId=0ZtQ0MvxQ8pob4h4mAsScreenshot 2025-05-20 142937

In addition to increasing leverage it also reduces the tolerance between the lever blade and master cylinder body which significantly reduces the bushing play present in stock cura levers. I've got a previous version I'm currently running that reduces bushing play but has about the same leverage as the formula "feel control" levers in the highest leverage setting but allow the lever to be run much closer to the bar. I found the range of reach adjust on the formula levers to be too far out. Those are 3d printed out of titanium and look like this:

IMG 3333

IMG 3335.jpeg?VersionId=mxY9AyHJzEBpcaeCw

I’ll be honest, that big of a change in master cylinder diameter doesn’t sound wonderful. Comparing the distance you’d have to move the master cylinder to...

I’ll be honest, that big of a change in master cylinder diameter doesn’t sound wonderful. Comparing the distance you’d have to move the master cylinder to move the pads the same amount, it’s a 56% increase. That’s a lot of lever throw… one conclusion I’ve come to is that massive power and good lever feel aren’t really attainable without decreased pad retract. Swing link kind of gets you there but there’s a stiff portion of lever throw it has to move through. 

Yeah I agree that seems like pushing it past the point of practicality. You can see in the video he’s having to run the lever reach super super far out to compensate.

1
mitch160
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5/20/2025 10:23pm
Figure a lot of people here will find this interesting:Basically he reduces the master cylinder diameter from 10 to 8mm which significantly increases hydraulic advantage. Also...

Figure a lot of people here will find this interesting:

Basically he reduces the master cylinder diameter from 10 to 8mm which significantly increases hydraulic advantage. Also the brake comparison website he shows is such a good resource: https://brakes.ddzyne.nl Not sure how no one's found it yet.

I'm actually doing something kind of similar with a set of brakes currently. Picked up a set of sram db8 calipers for cheap and am running them with formula cura levers (coming from cura 2 calipers). This results in quite a bit less power because of the reduced hydraulic ratio (4.36 vs 5.22) but you do gain access to like an order of magnitude more aftermarket pad options and get more piston rollback (pad-rotor clearance). Not wanting to mess with modifying internal components so I'm currently getting a new set of lever blades machined that increases mechanical advantage from 7.1 to 8.5. This will boost the total advantage to slightly higher than DHR Evos, Cura 4s, or Tech 3 V4s. Here's my lever design for those interested:

Screenshot 2025-05-20 143017.png?VersionId=0ZtQ0MvxQ8pob4h4mAsScreenshot 2025-05-20 142937

In addition to increasing leverage it also reduces the tolerance between the lever blade and master cylinder body which significantly reduces the bushing play present in stock cura levers. I've got a previous version I'm currently running that reduces bushing play but has about the same leverage as the formula "feel control" levers in the highest leverage setting but allow the lever to be run much closer to the bar. I found the range of reach adjust on the formula levers to be too far out. Those are 3d printed out of titanium and look like this:

IMG 3333

IMG 3335.jpeg?VersionId=mxY9AyHJzEBpcaeCw

Related to the video above, using a magura mt7 caliper might have helped due to a very small pad rollback compared to something like the trp's. might have also not to have needed to go so small on the master cylinder diameter as the mt7 calipers have 4x17mm pistons compared to the 4x16mm pistons on trp caliper. would be interesting to see the results of how the this would reduce the lever throw and maintain a similar level of hydraulic pressure within the system. (Not an engineer but just guessing)  

1
Jakub_G
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8/7/2019
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5/20/2025 10:47pm Edited Date/Time 5/20/2025 10:49pm
Figure a lot of people here will find this interesting:Basically he reduces the master cylinder diameter from 10 to 8mm which significantly increases hydraulic advantage. Also...

Figure a lot of people here will find this interesting:

Basically he reduces the master cylinder diameter from 10 to 8mm which significantly increases hydraulic advantage. Also the brake comparison website he shows is such a good resource: https://brakes.ddzyne.nl Not sure how no one's found it yet.

I'm actually doing something kind of similar with a set of brakes currently. Picked up a set of sram db8 calipers for cheap and am running them with formula cura levers (coming from cura 2 calipers). This results in quite a bit less power because of the reduced hydraulic ratio (4.36 vs 5.22) but you do gain access to like an order of magnitude more aftermarket pad options and get more piston rollback (pad-rotor clearance). Not wanting to mess with modifying internal components so I'm currently getting a new set of lever blades machined that increases mechanical advantage from 7.1 to 8.5. This will boost the total advantage to slightly higher than DHR Evos, Cura 4s, or Tech 3 V4s. Here's my lever design for those interested:

Screenshot 2025-05-20 143017.png?VersionId=0ZtQ0MvxQ8pob4h4mAsScreenshot 2025-05-20 142937

In addition to increasing leverage it also reduces the tolerance between the lever blade and master cylinder body which significantly reduces the bushing play present in stock cura levers. I've got a previous version I'm currently running that reduces bushing play but has about the same leverage as the formula "feel control" levers in the highest leverage setting but allow the lever to be run much closer to the bar. I found the range of reach adjust on the formula levers to be too far out. Those are 3d printed out of titanium and look like this:

IMG 3333

IMG 3335.jpeg?VersionId=mxY9AyHJzEBpcaeCw

Nice job, there is already aftermarket lever option for cura on the market though, with longer/shorter options and running on bearings instead of bushings too 🙂https://www.ebay.com/itm/125531213076

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