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The perfect bleed eludes me

Da Peach

Outwitted by a rodent
Jul 2, 2002
13,681
4,904
North Van
I've got 2012/13 XTR trail brakes. I want to get them bled perfectly.

I followed this procedure:

It didn't work very well.

I went to my shop and they told me NOT to open the free stroke all the way is instructed in the Shimano video. Also, they recommended that I leave the funnel on and pump the brakes over and over and over to try and force out any more air that might be hiding in the lever/lines...

I took this advice and tried again, and got better results, but it still isn't PERFECT.

I riding buddy has said that performing the bleed, but then leaving the funnel on, and putting an elastic on the lever and leaving the whole thing as such overnight is the ticket.

What are your thoughts methods?
 

yd35

Monkey
Oct 28, 2008
741
61
NY
I never really understood why you should unscrew the free stroke adjuster when you bleed, until I tried bleeding with it screwed all the way in. I could gravity bleed just fine (from the lever down) but I could not for the life of me push fluid up with a syringe (from the caliper up). After fuming for a few hours and chucking some wrenches, I figured out that unscrewing free stroke was the issue. If it's screwed all the way in, you can't push fluid at all. The more you unscrew, oil becomes progressively easier to push. So there's your answer folks, Shimano free stroke DOES work, just not in the way you'd expect.

Out of curiosity why did the shop advise you not to open free stroke all the way?
 

Da Peach

Outwitted by a rodent
Jul 2, 2002
13,681
4,904
North Van
i find it annoying how radically different Shimano's method is from the "epic bleed" method.

I've only got 1 piece of hose too... makes the caliper bleed step an extra PITA.
 

Da Peach

Outwitted by a rodent
Jul 2, 2002
13,681
4,904
North Van
I never really understood why you should unscrew the free stroke adjuster when you bleed, until I tried bleeding with it screwed all the way in. I could gravity bleed just fine (from the lever down) but I could not for the life of me push fluid up with a syringe (from the caliper up). After fuming for a few hours and chucking some wrenches, I figured out that unscrewing free stroke was the issue. If it's screwed all the way in, you can't push fluid at all. The more you unscrew, oil becomes progressively easier to push. So there's your answer folks, Shimano free stroke DOES work, just not in the way you'd expect.

Out of curiosity why did the shop advise you not to open free stroke all the way?

Hmm. Not sure why. They didn't explain. I was in "I'll just take your word for it" mode.

When I did attempt after visiting the shop, I was able to push fluid through. I guess the free stroke was partially open. I didn't consciously screw it in tight or anything...
 

OGRipper

back alley ripper
Feb 3, 2004
10,647
1,116
NORCAL is the hizzle
Come on, a "perfect" bleed is gonna take some extra steps. Once you work through it once or twice, those few extra steps should start to make sense, and shouldn't take much extra time. And you know you can find hose like that at any decent hardware store for pennies.

Anyway, it's the best method I've tried.
 

ButtersNZ

Monkey
Jun 6, 2013
176
10
I use a syringe with the funnel. Funnel in, put oil in there. Back off the caliper nipple a bit and draw oil into the syringe. Once clean stuff flows into the syringe, close the nipple and pump the brakes. Tap the lines, reposition the lever etc. Take new oil up into the syringe and push it through the nipple from the bottom to the top. First, draw it out slightly to remove any air from the syringe tubing. AFter this, the oil in the funnel should be pretty clean, use it again to flush the second brake line.

Bleed them twice. Once, after a days riding when you're ****ing furious at how "bad" your new top-spec Shimano's are. Then top them up the next day once any bubbles have risen up. They'll be mint.

Source - Saint M820's
 
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canadmos

Cake Tease
May 29, 2011
20,188
19,155
Canaderp
I never really understood why you should unscrew the free stroke adjuster when you bleed, until I tried bleeding with it screwed all the way in. I could gravity bleed just fine (from the lever down) but I could not for the life of me push fluid up with a syringe (from the caliper up). After fuming for a few hours and chucking some wrenches, I figured out that unscrewing free stroke was the issue. If it's screwed all the way in, you can't push fluid at all. The more you unscrew, oil becomes progressively easier to push. So there's your answer folks, Shimano free stroke DOES work, just not in the way you'd expect.

Out of curiosity why did the shop advise you not to open free stroke all the way?

Kind of off topic, but is there a limit on how much you can unscrew the free stroke adjustment?

I have some Saint brakes on a new bike and unscrewed them a bit, but afraid to go any further in case that they just fall out..
 

Da Peach

Outwitted by a rodent
Jul 2, 2002
13,681
4,904
North Van
^ yeah, I was kinda nervous about that too.

I've still not re-bled my brakes. They're feeling pretty good now. Close enough to perfect for me, for now.
 

OGRipper

back alley ripper
Feb 3, 2004
10,647
1,116
NORCAL is the hizzle
I use a syringe with the funnel. Funnel in, put oil in there. Back off the caliper nipple a bit and draw oil into the syringe. Once clean stuff flows into the syringe, close the nipple and pump the brakes. Tap the lines, reposition the lever etc. Take new oil up into the syringe and push it through the nipple from the bottom to the top. First, draw it out slightly to remove any air from the syringe tubing. AFter this, the oil in the funnel should be pretty clean, use it again to flush the second brake line.

Bleed them twice. Once, after a days riding when you're ****ing furious at how "bad" your new top-spec Shimano's are. Then top them up the next day once any bubbles have risen up. They'll be mint.

Source - Saint M820's
So your first step is to draw fresh oil into the system on top of your dirty fluid and any air in the lever?
 

ButtersNZ

Monkey
Jun 6, 2013
176
10
Yes, but the last step is to push fresh oil from the bottom to the top. If you're worried about drawing in bubbles from the lever, you could push a little oil up from the syringe before you draw it down.
 
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OGRipper

back alley ripper
Feb 3, 2004
10,647
1,116
NORCAL is the hizzle
Sure, but it seems better to just purge it from the bottom up 'til it runs clear, then deal with remaining bubbles, if any. That's one of the benefits of the newer shimano brakes, and it's basically the Epic Bleed method. It might seem like a lot of steps but that's just because they are very thorough in describing each step. But hey, if it works for you, rock it.
 

yd35

Monkey
Oct 28, 2008
741
61
NY
Kind of off topic, but is there a limit on how much you can unscrew the free stroke adjustment?

I have some Saint brakes on a new bike and unscrewed them a bit, but afraid to go any further in case that they just fall out..
I'm not sure, good question! I'm assuming you can just completely unscrew it from the lever, but I've never tried. I've always unscrewed it until a pretty decent amount of thread is showing. Not sure if I'm close to the end or if there's still a good amount left.