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Discussion Starter · #1 ·
I have a new set of M785 XT brakes on my 2014 Giant Anthem. I like my brakes stiff with not much squeeze before they lock for 1 finger braking. I find that after a ride or 2 they require much more squeezing to engage the pads. I've read that you can take the wheel off and squeeze the brake a couple times to get the pistons to set in further and this definitely helps for a ride or 2, but they always become too squishy. I am finding myself doing this quick fix after every ride now. I had a pair of SLX before and they were much firmer. Is there a way to fix this?
 

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Discussion Starter · #3 ·
that was my first idea. and i took them in to get bled and they felt the same. not stiff enough.
 

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Shimano brakes are somewhat prone to getting air trapped in the caliper. You can think you've got a good bleed until the air bubble moves. The recent design was supposed to eliminate this but it's still a good idea to do the pump and dump bleed process to finish off the bleed. Close the bleed valve, pump the lever until it's really firn, then crack the bleed port. This gives a rush of fluid that will flush out the corners of the system and yield a lasting firm lever.
 

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whatever she says gueuze.
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Did you ever get your brakes to feel firmer? I just installed a new set yesterday and feel like I have the same problem. I've bled them but haven't done the pump method.
 

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I like the same feel as the OP. After a few rides, I take the wheels off and pull the lever a couple of times to bring the pistons out to get the same feel. I've tried the bleeding and that doesn't seem to work. I just think that the pads get worn down a bit.
 

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Shimano runs an open system for their brakes. Every time you cycle the lever it gives the pressurized fluid a chance to equalize. So if you were on the breaks for 10 minutes and wore away half the pad it can pull in the appropriate amount of fluid to compensate. On the flip side if you heat and thus expand the fluid it can overflow into the reservoir. Most brakes run this basic design for obvious reasons. Notable exception would be the SRAM XX world cup that was designed for a pretty narrow group of riders, riders with their own traveling mechanic.
 

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i have had a look at various you tube and shimano spec bleeding procedures. Some of teh online mechanics stress the air trapped in the caliper, as in having to give it a good tap and move it around. what i ve added to this is i dont remove the top funnel from the resavoir until the caliper is on and the wheel in place, and i give the lever a few pulls and taps, ive found the rotor is a touch thinner than the "red" spacer. thereafter i close it up and the results have been fantastic. BEST brakes.
 
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