Always had Shimano SLX or XT, current/new bike came with GuideRE's, as soon as they need a bleed they're going on ebay, cba messing with dot fluid. Will be going back to shimano in a heartbeat.
Got some Dominions on my new bike which I bled out of the box and since then they have been faultless. Was always a big Shimano fan but since using these I will not be going back as they have stacks of power but in a controlled way with no hassle. Love them
Just took delivery of me new bike with the dominion A4 on it, back brake went all soft on me so gave bleeding it a try, honestly, such a good step by step tutorial, my brake feels mint again now, Thank you 😊
Thanks Owen, I've been waiting for you to do one on Hayes. Did you remove the old fluid first? If not, is that something that should be done at some point?
Good question! Essentially as your pushing more fluid from the bottom up it should replace the older fluid If you've used your brake a lot and the colour of the fluid thats being pushed up is much darker - potentially its worth closing off the lower syringe hose - removing it, then topping up with fresh fluid and reattaching the syringe - unlocking the syringe and feeding it through - you may need to hose lock the top and remove excess fluid from the upper syringe - iIve written that and it might sound overly complex but its simple cycling more fluid through the system to replace the old comtaminated fluid - Hope that helps? Cheers Owen
@@OwenBikeNerd Thanks for the reply Owen. Next video please, how to properly align your Hayes caliper and rotor once you put it back together and we will have the whole process.
#askGMBNtech 🤩 WOW - I am astonished about the trick (by purging and pulling a vacuum pressure) how to get even the tiny bubbles of air with its included moisture out of the syringe - how come I've never heard of this method for bleeding MTB brakes ? ... and would this procedure be good for mineral oil as well? Thanks a lot
@@KMWS hayes popularized this when they released their bleed video it always made sense but wasnt very well known. in practice this lets you use old dot fluid if you do this enough and have good seals.. but.. you know.
Anything that uses dot is a dealbreaker for me, too much hassle. This procedure looks like a lot of hassle as well, but the trick with negative pressure to remove bubbles/moisture is really neat!
mineral fluid is hydrophobic anyway so has no water, and thus, no air, so you just need to get bubbles out. dot is hydroscopic, so it attracts water and water contains air. when pressured the air is separated and becomes air bubbles which, are compressible and make brakes feel spongy. so you get any potential air out from the fluid itself while bleeding first. in that regard mineral is superior but in practice stuff gets into the system while riding and both need bleeding. a bad dot bleed will also feel better than a bad mineral bleed because of its ability to absorb water. fun !
#askGMBNTech doesn’t this mix up the fresh oil with the old oil that may contain moisture? I think I’d sooner do a push through of new oil capturing the old oil that comes out for disposal and then perform this bubble removal method (which does seem very comprehensive) on all the fresh oil that’s in there.
You are pulling air through the bleed fittings. You need to put a tool on them to make a good seal. Or use the old SRAM kit that has an orange on the fitting
#askgmbntech if all brakes are constructed similarly (master cylinder with reservoir, hose, caliper with bleed port), why every manufacturer has their own procedure?
Great question ! You are right - lots of hydraulic brakes do have similar functional constructions - but the subtle differences in construction and how they function do result in different bleed procedures - at least at the specific step by step level - of course from a big picture view all the bleed procedures are very similar in wanting as little air in the system as possible. Cheers Owen
@@OwenBikeNerd thank you for the answer! My take was due to use of different liquids (like DOT really needing to be vacuumed and different mineral oils with the different viscosity may trasfer bubbles easy or hard) and patented fittings. But I guess the internal geometry plays a role too🤔
What brakes do you have? Have you ever bled a brake? 🤔💬👇
Always had Shimano SLX or XT, current/new bike came with GuideRE's, as soon as they need a bleed they're going on ebay, cba messing with dot fluid. Will be going back to shimano in a heartbeat.
Perfect timing Owen as I was going to do a first bleed of my Dominion A4 brakes in the next couple of weeks - thanks!
enjoy them!
Got some Dominions on my new bike which I bled out of the box and since then they have been faultless. Was always a big Shimano fan but since using these I will not be going back as they have stacks of power but in a controlled way with no hassle. Love them
Just took delivery of me new bike with the dominion A4 on it, back brake went all soft on me so gave bleeding it a try, honestly, such a good step by step tutorial, my brake feels mint again now,
Thank you 😊
I should get this right “eventually” but I’d need about a gallon of fluid because of all the mistakes I’d make. This looked complex but doable
Awesome brakes 👍
;)
Easy peasy. You got a subscriber!
Thanks Owen, I've been waiting for you to do one on Hayes. Did you remove the old fluid first? If not, is that something that should be done at some point?
Good question!
Essentially as your pushing more fluid from the bottom up it should replace the older fluid
If you've used your brake a lot and the colour of the fluid thats being pushed up is much darker - potentially its worth closing off the lower syringe hose - removing it, then topping up with fresh fluid and reattaching the syringe - unlocking the syringe and feeding it through - you may need to hose lock the top and remove excess fluid from the upper syringe - iIve written that and it might sound overly complex but its simple cycling more fluid through the system to replace the old comtaminated fluid -
Hope that helps?
Cheers
Owen
@@OwenBikeNerd Thanks for the reply Owen. Next video please, how to properly align your Hayes caliper and rotor once you put it back together and we will have the whole process.
#askGMBNtech 🤩 WOW - I am astonished about the trick (by purging and pulling a vacuum pressure) how to get even the tiny bubbles of air with its included moisture out of the syringe - how come I've never heard of this method for bleeding MTB brakes ? ... and would this procedure be good for mineral oil as well? Thanks a lot
@@KMWS hayes popularized this when they released their bleed video it always made sense but wasnt very well known. in practice this lets you use old dot fluid if you do this enough and have good seals.. but.. you know.
so you're using a third syringe for the two stroke bleed while the one on the master is still attached?
Anything that uses dot is a dealbreaker for me, too much hassle. This procedure looks like a lot of hassle as well, but the trick with negative pressure to remove bubbles/moisture is really neat!
these are worth it, nice light lever feel compared to nearly all mineral oil brakes
mineral fluid is hydrophobic anyway so has no water, and thus, no air, so you just need to get bubbles out. dot is hydroscopic, so it attracts water and water contains air. when pressured the air is separated and becomes air bubbles which, are compressible and make brakes feel spongy. so you get any potential air out from the fluid itself while bleeding first.
in that regard mineral is superior but in practice stuff gets into the system while riding and both need bleeding. a bad dot bleed will also feel better than a bad mineral bleed because of its ability to absorb water. fun !
Hi @gmbntech can you possibly do a review of ltwoo derailleur and shifter?
Love your show
#askGMBNTech doesn’t this mix up the fresh oil with the old oil that may contain moisture? I think I’d sooner do a push through of new oil capturing the old oil that comes out for disposal and then perform this bubble removal method (which does seem very comprehensive) on all the fresh oil that’s in there.
You are pulling air through the bleed fittings. You need to put a tool on them to make a good seal. Or use the old SRAM kit that has an orange on the fitting
#askgmbntech if all brakes are constructed similarly (master cylinder with reservoir, hose, caliper with bleed port), why every manufacturer has their own procedure?
Great question !
You are right - lots of hydraulic brakes do have similar functional constructions - but the subtle differences in construction and how they function do result in different bleed procedures - at least at the specific step by step level - of course from a big picture view all the bleed procedures are very similar in wanting as little air in the system as possible.
Cheers
Owen
@@OwenBikeNerd thank you for the answer! My take was due to use of different liquids (like DOT really needing to be vacuumed and different mineral oils with the different viscosity may trasfer bubbles easy or hard) and patented fittings. But I guess the internal geometry plays a role too🤔
Ahem... "Hexalobular Internal" not torque wrench.
And I know you meant Torx, but I heard "torque" and so did google when they captioned it. 😜
Bleed kit only comes with two syringes
DOT fluid is a deal breaker. Mineral oil so much easier to deal with.
HOPE
Dot fluid seems to much hassle and danger and absorbs moisture
Can you do TRP DH EVO Pls 🤘🏻
Ooo - Great question - we're try and get one organised!
Cheers
Owen
Call me shallow, but orange and purple?
Shallow.
Purple Hayes Dominion is limited edition version - but you can get a different colour Dominion - the bleed process is the same!
Cheers
Owen
How to do it: 1 Use mineral oil brakes, 2 enjoy that hour of time you saved doing something else. Done.
Just a joke, Hayes brakes are great!
They might be great brakes but somewhat complicated for a novice mechanic.