Bleeding Brakes
Discussion
Morning all,
Having an issue with my rear brake, Deore 2 pots:
I've bled them up from the bottom, let them drain back down from the top, wiggled the reservoir around, all of the right things, and I don't think there's any air left in there.
With the bleed block in place, it firms right up nicely, the level feels great.
As soon as I take it out and refit the caliper and pads, it's soft as a soft thing.
Should I forget about the bleed block, and bleed them with the wheel & pads fitted?
Having an issue with my rear brake, Deore 2 pots:
I've bled them up from the bottom, let them drain back down from the top, wiggled the reservoir around, all of the right things, and I don't think there's any air left in there.
With the bleed block in place, it firms right up nicely, the level feels great.
As soon as I take it out and refit the caliper and pads, it's soft as a soft thing.
Should I forget about the bleed block, and bleed them with the wheel & pads fitted?
TheTardis said:
They do feel a bit softer than the 2 pots.
Do they work? If so, leave at that.
They are the 2 pots? Do they work? If so, leave at that.
No, they don't really work. Not enough pressure. Good clean discs and new pads. I know the pads will need to be bedded in, but the level doesn't feel right at all.
Fine with the bleed blocks in place, awful with the pads and discs fitted.
Does it improve if you pump the brake a number of times? It's normal for there to be a bit of free travel before the brake bites, but the bite point shouldn't change as you pump the brake.
I had to bleed my front brake 3 times before they worked properly. There was a trapped air bubble that the normal "bottom up" method failed to clear, but I got it in the end by using the top-down method.
I had to bleed my front brake 3 times before they worked properly. There was a trapped air bubble that the normal "bottom up" method failed to clear, but I got it in the end by using the top-down method.
There's a trick with shimano brakes to come back a day/ride layer and perform a lever bleed or burp after you have bled them. Just a case of removing the lever bleed bolt, putting the shimano reservoir in and adding some oil, then pumping the lever to get the air out.
Another thing I like to do with all brakes is to push and pull the fluid a few times with the syringe to remove air. Something Magura owners will know to do.
I also use Putoline 2.5w fork oil not the shimano stuff which allows air bubbles to move and escape easily
Another thing to do after bleeding is to pump the lever slightly (half way) and bring the pistons in slightly which results in a firmer feeling lever and a faster bite point.
Also to add, deore 2 piston brakes with metal pads and sram centreline rotors are by far the most powerful brakes I've ever had, better than XT 4 piston and the Magura MT7.
Another thing I like to do with all brakes is to push and pull the fluid a few times with the syringe to remove air. Something Magura owners will know to do.
I also use Putoline 2.5w fork oil not the shimano stuff which allows air bubbles to move and escape easily
Another thing to do after bleeding is to pump the lever slightly (half way) and bring the pistons in slightly which results in a firmer feeling lever and a faster bite point.
Also to add, deore 2 piston brakes with metal pads and sram centreline rotors are by far the most powerful brakes I've ever had, better than XT 4 piston and the Magura MT7.
Edited by Bathroom_Security on Monday 13th September 09:29
Bathroom_Security said:
Also to add, deore 2 piston brakes with metal pads and sram centreline rotors are by far the most powerful brakes I've ever had, better than XT 4 piston and the Magura MT7.
Do the metal pads cause any issues with the Deore brakes? Shimano say the deores I have are compatible with resin pads only, which I read somewhere is because they have resin pistons. Probably just Shimano being overly conservative...IME you need to do the push from both ends with two syringes. They don't seem to follow logic, mine will expel air bubbles from the caliper end on the push despite that being the lowest point of the system (bike in a stand with the nose pointed up). Bubbles don't seem to find their own way up, but pushing the whole system back and forth gets it out. If particularly troublesome, shutting the caliper nipple and giving the lever a squeeze or two can help.
uncinqsix said:
Do the metal pads cause any issues with the Deore brakes? Shimano say the deores I have are compatible with resin pads only, which I read somewhere is because they have resin pistons. Probably just Shimano being overly conservative...
I had deore 6000 and from memory they had metal pistons. Better than those s
tty ceramics in the XTs which shatter. I had 2 XT calipers fail, couldn't get hold of a new one because covid so ended up buying a set of MT7s. I had no issues with my deore at all and I just got upgradeitus. Had no issues with the shimano metal pads cant remember the model name, same compound as L04C
I'm not averse to doing the final set up with the disc and pads in place, but only from the lever end to avoid the risk of contamination on the disc/pad.
In theory, this should give you the perfect set up, but you do have the potential disadvantage of no clearance and the brake binding on due to thermal expansion, for example.
If you are using old, worn pads, and switch to new thicker pads, you might need to release some fluid.
In theory, this should give you the perfect set up, but you do have the potential disadvantage of no clearance and the brake binding on due to thermal expansion, for example.
If you are using old, worn pads, and switch to new thicker pads, you might need to release some fluid.
wildgfish said:
Make sure the caliper is aligned properly on the disc. This solved the same problem for me.
I've centered it about the disc when refitting, and I've fitted new pads, the old ones were barely worn tbh, but I've fitted new ones anyway.Looks like I'll go back and fiddle with it some more after work, I'll try some of the tips mentioned on the thread, thanks all.
Bled 2 bikes with Deore on last week. The front on both are now proper bombers and bite on both straight away.
The rears are not so instant and need more travel to bite straight away. A "fuzzier" feel versus the digital of the fronts.
This was after pushing up from the caliper and pushing/pulling at each end. Only thing I didn't do was remove the caliper so difference could be the caliper was higher than the hose.
The rears are not so instant and need more travel to bite straight away. A "fuzzier" feel versus the digital of the fronts.
This was after pushing up from the caliper and pushing/pulling at each end. Only thing I didn't do was remove the caliper so difference could be the caliper was higher than the hose.
To provide closure, I got pissed off with it and didn't touch the bike for nearly 2 weeks.
When I did, they work absolutely perfectly.
I can only assume that some small amount of air was still present and has worked it's way up to the reservoir?
Thanks for all the replies at the time though
When I did, they work absolutely perfectly.
I can only assume that some small amount of air was still present and has worked it's way up to the reservoir?
Thanks for all the replies at the time though
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