You leave the pistons out swinging in the breeze during the bleed? Do you have a "padrotorpad" thickness bleed block? They you shove the pistons into the caliper and let the overflow surge up into the lever syringe?
Hmmm...
Frankenbrakes and brake improvement discussion
- Thread starter Udi
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Hmmm...
Another thing that made me think of it is that I had one operation in Jan. that completely immobilized one thumb, and I’m having the other done soon. This would simplify one hand operation greatly. (I couldn’t use a syringe solo)
The quick connect for Shimano has needed to happen for decades.
The quick connect for Shimano has needed to happen for decades.
Yep. The hose popping off the caliper is maddening...
I generally just stick a precision trimmed piece of scrap wood in there, pump up the brakes with a syringe on the lever. Pull a vacuum on the syringe, walk away for 15 minutes then push the pistons out. I may have to repeat once.
On track days we'd use these 'power bleeders' on our cars' master cylinders. Could you misuse something like that to make quick work of initial setup/bleeds?
That’s the precise idea, with a low flow, low power pump to just help things along. The Shimano quick-connect is gonna be harder to figure out.
I am thinking of using a foot switch to shut the pump off when I’m ready to close the bleed port.
So far it’s a $17.00 experiment, I mean, why the fuck not.
I am thinking of using a foot switch to shut the pump off when I’m ready to close the bleed port.
So far it’s a $17.00 experiment, I mean, why the fuck not.
That is what a syringe ultimately does
I mean, if you rigged something to pressurize say 10 MCs at once, since the larger canister would provide ample volume at pressure, you could bleed 10 brakes at the calipers at the same time.
Reading comprehension is not my thing.
I mean, if you rigged something to pressurize say 10 MCs at once, since the larger canister would provide ample volume at pressure, you could bleed 10 brakes at the calipers at the same time.
Reading comprehension is not my thing.
So they had "bulk" pressure bleeders?
I am only familiar with the ones that just pressurize the master cylinder allowing you to crack the bleeder at the caliper. I still always used a vacuum pump to de-gas the fluid before pressure bleeding. Surprising how much air will come out of fresh fluid. I know people who will keep fluid under vacuum for a few days prior filling, in theory to pull any moisture out.
Anyway if you have access to high ceilings a simple pressure bleeder can just be a canister with a long tube.
My Dominions have been pretty much this:
View attachment 218956
Bleeds. Ain't nobody got time for that!
All my brakes have been like that.
Well except for OG Hope Monos. Bleeding those was just a futile attempt at fixing major design/manufacturing issues with maintenance.
imho those are only good for dosing stuff, not build up pressure. i rather use something for camper vans/boats
It would have to be pulled down till it boiled wouldn't it?
I have some old brake fluid in the garage and some rain is coming so I might do some myth testing.
We were told "A bottle of brake fluid will be ruined in an hour if you leave the lid off on a humid day"
I have a brake fluid boiler so I'll see if it's true and see if part empty 10yr old stuff has degraded.
We were told "A bottle of brake fluid will be ruined in an hour if you leave the lid off on a humid day"
I have a brake fluid boiler so I'll see if it's true and see if part empty 10yr old stuff has degraded.
This is kinda what I was thinking of. They have existed forever and its pretty common in the automotive world. Something like this...
My only fear is pressurizing the master on a Shimano brake hurting the diaphragm.
What is the best way to do this? I've been wanting to vacuum brake fluid and suspension oil just cant wrap my head around the best way.
If you have a moment to post a link to something more suitable, I would greatly appreciate it.
Well, in theory, there would never be pressure on without the lever bleed screw open, and the funnel attached.
Wouldn't it make sense to use a material that doesn't compress under pressure like steel or aluminium? I once tried to bleed motorcycle brakes on the table with a piece of wood in the caliber and it never was good until I attempted an aluminium plate.
It used to be part of the instructions from Avid/SRAM just using the syringe with the clamp closed off on the hose. Pull the plunger and flick the syringe as the small bubbles form to make them rise/gather together.
peristaltic pumps are great to dose say hydroponic feeding solution for your favorite bongshed herb, which i know nothing about how to grow them, i‘d go with a camper pump:
also look at these contraptions:
BK on Instagram: "Trying some things with @radarlaboratories Bleed bucket or syringe? #bikemechanicthings"
1,030 likes, 43 comments - bee_kay77 on June 2, 2023: "Trying some things with @radarlaboratories Bleed bucket or syringe? #bikemechanicthings".
www.instagram.com
BK on Instagram: "Big dog 100ml @radarlaboratories "
689 likes, 27 comments - bee_kay77 on May 25, 2023: "Big dog 100ml @radarlaboratories ".
www.instagram.com
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What @6thElement said. If you want to do this via another method, or with a car, a simple manual vacuum bleeder will do the trick.
Brake Bleeder and Vacuum Pump Kit
Amazing deals on this Brake Bleeder And Vacuum Pump Kit at Harbor Freight. Quality tools & low prices.
You can use the the little canister that comes with the kit and block off one end, but easy to cross contaminate with dirty fluid. I glued in a small barb into the lit of a mason jar, put fluid into the jar and suck.
I pump the lever to move the pistons out but don't push hard, never been a problem. The wood spacer is just there to stop the pistons from falling out (ask my how I know). I don't even open the bleed port on the calipers when doing this.
I had a set of XT brakes I could never get to firm up. Wound up massaging the pistons out and back in while bleeding and fixed it.
That is the benefit of using piston movement to bleed the brakes, there is sufficient displacement to move pretty much any fluid with an air pocket back up to the lever. Pushing oil from the caliper bleed may not flow correctly to displace all the air. Pulling some vacuum on the lever syringe will make the bubbles bigger and easier to push back into the line.
So if Shimano Saint M820 takes at maximum a 2,00mm thick brake disc, I need to make a Braking/BCA-style 1,00 - 1,20mm thick adapter for a 3mm brake disc.
Some measurement
Max width in the brake caliper: 11,7mm
New OEM H03C brake pads width: 4,00mm
Space left between 2,00mm disc and new pads: 11,7mm - 2 x 4,00mm = 3,7mm
Sounds dangerous, but not impossible? Feel free to confirm or correct the measurements and logic.
Some measurement
Max width in the brake caliper: 11,7mm
New OEM H03C brake pads width: 4,00mm
Space left between 2,00mm disc and new pads: 11,7mm - 2 x 4,00mm = 3,7mm
Sounds dangerous, but not impossible? Feel free to confirm or correct the measurements and logic.
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Seems correct.
What is the thickness of the o-rings between each halves of the caliper? And how deep is the recess for these o-rings?
You will now need an o-ring on each side of the adapter which might be tricky considering how thin the adapter will be...
Maybe having a recess on each halves would work?
4mm ones seem good, just fitted two of them into lonely calipers in our home fleet.
Link:
TRP brakes with Shimano hoses Been running this setup on all of my race bikes for nearly 2 years now. @victordh12 introduced this concept to me and It’s been a game changer. It gives a noticeably nicer bite to the brakes. A much more definite bite point. Thought I’d share if anyone wanted to get a bit more out of their TRP brakes. Big fan of the TRP’s overall
I assume most brake hoses have inner tubes made of polyurethane (PU), so how could changing the brake house have any significant effect on the brake lever feel? Changing the hose needs bleeding which might be a much bigger variable I guess.
Does steel braiding really on top of the PU innertube have any effect? I wonder if innertube material has any variable on width change under pressure.
TRP brakes with Shimano hoses Been running this setup on all of my race bikes for nearly 2 years now. @victordh12 introduced this concept to me and It’s been a game changer. It gives a noticeably nicer bite to the brakes. A much more definite bite point. Thought I’d share if anyone wanted to get a bit more out of their TRP brakes. Big fan of the TRP’s overall
I assume most brake hoses have inner tubes made of polyurethane (PU), so how could changing the brake house have any significant effect on the brake lever feel? Changing the hose needs bleeding which might be a much bigger variable I guess.
Does steel braiding really on top of the PU innertube have any effect? I wonder if innertube material has any variable on width change under pressure.
Changing the ones on my old Magura Louise and Marta made a huge difference, but the stock hoses have supposedly been upgraded since then.
What's your goal with going to 3mm rotors, are you warping your stock ones?
Seems like a good way to get more heat soak for potentially no benefit.
No, I just want to test and try things especially products that are developed in the bicycle bubble.
Nice, thanks, something I'd completely overlooked on a bike.
On my first car I used to have to get the brakes hot before it went for its annual inspection so it didn't fail the brake test.
Science from Sram, I think that's a new one.
very interesting stuff, I have a bowhead reach (adaptive MTB trike) with Magura mt7s all round, the front 2 calibers are driven by the one leaky leaver. I have been told the front brakes are tuned to closer tolerances than normal to fit enough fluid in for them to work, im pretty used to it but considering the leaver is stuffed Im looking into running another leaver with I guess higher volume to be closer to the feel of running a single caliper, does anyone know of info on master cylinder sizes/ratios etc and or compatibility ,
+rep for Yngwie
Trickstuff levers sport a relatively large reservoir, 3 ml afaik
depends, what brakes are currently in use? EVOs are great, so long as you jive with their levers IMO.