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'brifter' is f'ing stupid
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Actually, thinking about this, mineral oil doesn't absorb water and water collects at the low point in the system, which is in the caliper, so I think you need to do a gravity bleed through the funnel out through the caliper to remove any water. I don't think pushing fresh fluid through the other direction can effectively remove this water.
I guess that would make you smarter than Shimano's legions of highly trained and very experienced engineers. You should contact Shimano and let them know what they're missing.
 

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Discussion Starter #22
I guess that would make you smarter than Shimano's legions of highly trained and very experienced engineers. You should contact Shimano and let them know what they're missing.
Actually, the manual says to bleed from the funnel out through the caliper into a catch bag, as well as the opposite way with the syringe, so my comment was consistent with the Shimano instructions.
 

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'brifter' is f'ing stupid
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Don't you have a Shimano bleed kit? Did it come w/ anything other than a cup and a syringe?
 

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No, I push the fluid up from the caliper to the lever. I change the angle of the bike in the stand rather than loosening the bars. When I think I've got fresh fluid all the way through and don't see any more bubbles I'll take the syringe off and pull on the lever to see how it feels. I will usually finish up by pumping the lever a bunch to make sure I've got all the small bubbles out (you'll see them go into the cup) and that's it. I never seem to need to go from the lever to the caliper.
I bled the R785s on my gravel bike last weekend. My mech said only need to gravity bleed, also pumped the levers and force bleed, and also rotated the bars and flicked the levers, which also brought up bubbles. Didn't syringe bleed. Not saying what's wrong or right, cx, feel free to critique. Brakes felt solid, but I had hip surgery recently and can't give a ride report for at least another week. Brake fluid coming out looked like Powerade Arctic Blast, but darker.
 

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'brifter' is f'ing stupid
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It's amazing how bad Shimano mineral oil can look after a year or so. It goes in pink, comes out grey. Sounds like you got it working pretty well. You can bleed either direction, they both work. I have multiple kits w/ the syringe and cup at my disposal so I use those as they're easy and clean. I bled some old Saint brakes the other day moto style as they have the cover that comes off the reservoir to bleed them. Pumped oil from the lever down. They felt amazing when I was finished. 15 year old brakes felt absolutely brand new.
 

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That's all it came with.

See these instructions Manuals & Technical Documents pages 34 and 58.
damn that's some nice instructions! One thing about Shimano is that their instructions are the gold standard in this industry.

Next up, caliper rebuild and swaping out the plastic hoses for braided steel ones.
Braided steel feels a world of difference, especialy for the rear since the line here is long and it benefits most from a rigid steel line. Will feel like you got upraded brakes. :cool::p:D
 

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Discussion Starter #28
I think there's a lot of crap YouTube videos on bleeding Shimano brakes. I saw some that didn't say to remove the pads, push the pistons back, and use a bleed block.
 

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I think there's a lot of crap YouTube videos on bleeding Shimano brakes. I saw some that didn't say to remove the pads, push the pistons back, and use a bleed block.
As with any topic, chose your YouTube source carefully. Is it a reputable site or just some schmoey hamfisted home mechanic who knows more about posting YouTube videos than about bike mechanics?
 

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I think there's a lot of crap YouTube videos on bleeding Shimano brakes. I saw some that didn't say to remove the pads, push the pistons back, and use a bleed block.

Park Tool has a lot on youtube. Generally a good place to start.
 
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