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
- Start date
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"
1,023 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 "
687 likes, 27 comments - bee_kay77 on May 25, 2023: "Big dog 100ml @radarlaboratories ".
www.instagram.com
Last edited:
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.