Nerding out on Brakes shall we? Not another tech deraliment

AndehM
Posts
631
Joined
5/7/2018
Location
El Granada, CA US
Fantasy
4/28/2026 9:09am
TheFBI wrote:
Is anyone having issues with their Mavens needing constant bleeding? I'm on Maven Ultimate A1's and it's driving me insane. About 1 month after a full...

Is anyone having issues with their Mavens needing constant bleeding? I'm on Maven Ultimate A1's and it's driving me insane. About 1 month after a full bleed and perfect performance, they're back to feeling way off - they're sucking in air somehow. It's not a piston massage thing, there's no oil leaking out anywhere, my brake fluid is fresh... Every time I bleed them : more air. I'm starting to think my set are faulty which would be a shame since they're my favourite brake.

I don't think it's a bleed technique thing (I do the same process on my Codes which are perfect all year) but for reference : connect up both syringes, pull slight vacuum as I connect them to pull up any air gap in the connector, then flush fresh fluid into the system from caliper to lever, then close off caliper, pull lever in and vaccum syringe, compress syringe and let go of lever, repeat until bubbles stop. 

Any opinions would be greatly appreciated 

Have you checked the torque on the hose nut?  I've had that be the cause of that behavior on various brakes in the past.  Refer to the "Dumb Bike Problems" thread... it's more than you think, but you should use a torque wrench because it is possible to crack the nut or hose olive if you go too far.

1
4/28/2026 9:42am

Yeah I would start looking at the connections at MC if there's something wrong, I for one have managed to install olive or two crooked.

1
storm.racing
Posts
307
Joined
2/15/2022
Location
Silverton, CO US
4/28/2026 9:56am
TheFBI wrote:
Is anyone having issues with their Mavens needing constant bleeding? I'm on Maven Ultimate A1's and it's driving me insane. About 1 month after a full...

Is anyone having issues with their Mavens needing constant bleeding? I'm on Maven Ultimate A1's and it's driving me insane. About 1 month after a full bleed and perfect performance, they're back to feeling way off - they're sucking in air somehow. It's not a piston massage thing, there's no oil leaking out anywhere, my brake fluid is fresh... Every time I bleed them : more air. I'm starting to think my set are faulty which would be a shame since they're my favourite brake.

I don't think it's a bleed technique thing (I do the same process on my Codes which are perfect all year) but for reference : connect up both syringes, pull slight vacuum as I connect them to pull up any air gap in the connector, then flush fresh fluid into the system from caliper to lever, then close off caliper, pull lever in and vaccum syringe, compress syringe and let go of lever, repeat until bubbles stop. 

Any opinions would be greatly appreciated 

have you checked torque on the banjo? There have been some comments similar to yours almost exactly and a few have found the cause to be loose banjo

1
ebruner
Posts
349
Joined
3/29/2018
Location
Tustin, CA US
4/28/2026 10:03am

It is really hard to get all of the air out of the maxima mineral oil with how thick it is.  If you airate the mineral oil when you pull it into the syringe, you're almost guaranteed to have micro bubbles in it that are impossible to deal with.  I am really deliberate about letting the syringes sit for 30 minute after filling them to let the air fully come out of the fluid.  Also advisable to lubricate the plungers on your bleed syringes before you start so you don't have to yank them super fast to break the stiction when filling the syringes up.  

For this reason, I do have a better success rate bleeding maven's with a bleed cup vs two syringes.  Between the risk of pulling too much vacuum and pulling air past the syringe o-rings and air bubbles trapped in the mineral oil, the bleed cup is way easier.  I'm about 80% successful in bleeding maven brakes on a 1 and done method.  1/5 times, I need to do at least a secondary lever bleed to get some air bubbles that come out on the first ride, or after the brakes have sat over night.  

2
4/28/2026 10:15am
TheFBI wrote:
Is anyone having issues with their Mavens needing constant bleeding? I'm on Maven Ultimate A1's and it's driving me insane. About 1 month after a full...

Is anyone having issues with their Mavens needing constant bleeding? I'm on Maven Ultimate A1's and it's driving me insane. About 1 month after a full bleed and perfect performance, they're back to feeling way off - they're sucking in air somehow. It's not a piston massage thing, there's no oil leaking out anywhere, my brake fluid is fresh... Every time I bleed them : more air. I'm starting to think my set are faulty which would be a shame since they're my favourite brake.

I don't think it's a bleed technique thing (I do the same process on my Codes which are perfect all year) but for reference : connect up both syringes, pull slight vacuum as I connect them to pull up any air gap in the connector, then flush fresh fluid into the system from caliper to lever, then close off caliper, pull lever in and vaccum syringe, compress syringe and let go of lever, repeat until bubbles stop. 

Any opinions would be greatly appreciated 

My red splatter Mavens were like this, every 3 months on the dot. I replaced pretty much every part but the pistons and seals and nothing helped. Changed to the teal splatter and they've been flawless for going on 9+ months. I have no explanation or helpful input,  just commiserating 

1
thresh
Posts
114
Joined
10/18/2023
Location
San Jose, CA US
Fantasy
4/28/2026 11:44am Edited Date/Time 4/28/2026 12:00pm
TheFBI wrote:
Is anyone having issues with their Mavens needing constant bleeding? I'm on Maven Ultimate A1's and it's driving me insane. About 1 month after a full...

Is anyone having issues with their Mavens needing constant bleeding? I'm on Maven Ultimate A1's and it's driving me insane. About 1 month after a full bleed and perfect performance, they're back to feeling way off - they're sucking in air somehow. It's not a piston massage thing, there's no oil leaking out anywhere, my brake fluid is fresh... Every time I bleed them : more air. I'm starting to think my set are faulty which would be a shame since they're my favourite brake.

I don't think it's a bleed technique thing (I do the same process on my Codes which are perfect all year) but for reference : connect up both syringes, pull slight vacuum as I connect them to pull up any air gap in the connector, then flush fresh fluid into the system from caliper to lever, then close off caliper, pull lever in and vaccum syringe, compress syringe and let go of lever, repeat until bubbles stop. 

Any opinions would be greatly appreciated 

What helped me in the same situation is to overtighten the caliper bolts way past their stated torque setting.

Also, check if the hoses are tightly screwed in.

(Based on my experience with A1 Red splatter and A1 regular ultimate)

1
ebikeluver
Posts
31
Joined
7/16/2025
Location
Terrace, BC CA
4/28/2026 2:44pm
ebruner wrote:
It is really hard to get all of the air out of the maxima mineral oil with how thick it is.  If you airate the mineral...

It is really hard to get all of the air out of the maxima mineral oil with how thick it is.  If you airate the mineral oil when you pull it into the syringe, you're almost guaranteed to have micro bubbles in it that are impossible to deal with.  I am really deliberate about letting the syringes sit for 30 minute after filling them to let the air fully come out of the fluid.  Also advisable to lubricate the plungers on your bleed syringes before you start so you don't have to yank them super fast to break the stiction when filling the syringes up.  

For this reason, I do have a better success rate bleeding maven's with a bleed cup vs two syringes.  Between the risk of pulling too much vacuum and pulling air past the syringe o-rings and air bubbles trapped in the mineral oil, the bleed cup is way easier.  I'm about 80% successful in bleeding maven brakes on a 1 and done method.  1/5 times, I need to do at least a secondary lever bleed to get some air bubbles that come out on the first ride, or after the brakes have sat over night.  

Which bleed cup fits?

1
TEAMROBOT
Posts
1390
Joined
9/2/2009
Location
Los Angeles, CA US
Fantasy
18 hours ago Edited Date/Time 18 hours ago
ebikeluver wrote:

Which bleed cup fits?

Jakub_G wrote:

Pinner Machine Shop also makes an adapter for the Shimano bleed cup to fit on SRAM mineral oil brakes. Once you have the adapter, you can use the fancy billet aluminum Pinner bleed cup or a standard white plastic Shimano cup.

The adapter is only $13 USD. Worth it's weight in gold: https://pinnermachineshop.com/en-us/products/bleed-cup-adapter?variant=41552493150305 

I agree with others about the efficacy of the lever bleed method to get any tricky air bubbles out of a Maven bleed, especially when they emerge over the course of a ride or two after a bleed. I've found a lot of luck doing the overnight lever ziptie/bleed cup method as a way to get any final air bubbles out. And I agree that there's something going on with the SRAM bleed kit, the Maven architecture, or Maxima's mineral oil that makes it really hard to get a consistent air-free bleed. Maybe it's all three.

1
jbfiets
Posts
18
Joined
1/18/2025
Location
sailsbury, NC US
7 minutes ago
TEAMROBOT wrote:
Pinner Machine Shop also makes an adapter for the Shimano bleed cup to fit on SRAM mineral oil brakes. Once you have the adapter, you can...

Pinner Machine Shop also makes an adapter for the Shimano bleed cup to fit on SRAM mineral oil brakes. Once you have the adapter, you can use the fancy billet aluminum Pinner bleed cup or a standard white plastic Shimano cup.

The adapter is only $13 USD. Worth it's weight in gold: https://pinnermachineshop.com/en-us/products/bleed-cup-adapter?variant=41552493150305 

I agree with others about the efficacy of the lever bleed method to get any tricky air bubbles out of a Maven bleed, especially when they emerge over the course of a ride or two after a bleed. I've found a lot of luck doing the overnight lever ziptie/bleed cup method as a way to get any final air bubbles out. And I agree that there's something going on with the SRAM bleed kit, the Maven architecture, or Maxima's mineral oil that makes it really hard to get a consistent air-free bleed. Maybe it's all three.

The SRAM Maven/Motive/DB lever fitting is M4 threads. The Shimano bleed cup thread is M5. I use the Park Tool fitting adapter (part 2600A, $6 each) included in their mineral bleed kit to go between the two.

I also use the M5 adapter w/ the bleed cup for Shimano brakes because the plastic bleed cup threads wear out really fast when you are bleeding multiple brakes per day.

I spent about 2 1/2 hours installing 1 maven caliper/lever and bleeding the other on a DH bike because I really wanted to get it right the first time. Will see what they say when they ride it. The lever had to be replaced because it seems like someone installed the olive backwards, I couldn't get the hose out of the lever even with pliers/twisting and the compression nut had been overtightened and turned oval.

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