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Discussion Starter · #1 ·
Has anyone managed to get Shimano m8000s to feel consistent on the front and rear?

I've bled these things to death but the rear always feels squishier than the front. I've also got m6000 mt500 and mt400 on other bikes, bled the exact same way and they're consistent. I've tried top down, bottom up bleeds, I've also tried lever depressed during final top off and sucking fluid through the caliper. Nothing seems to be helping.

Also once you adjust the reach the problem becomes more pronounced. At full extension it is only subtle.

I've almost given up these brakes. Tempted to change them out.
 

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Pizzaiolo Americano
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Has anyone managed to get Shimano m8000s to feel consistent on the front and rear?

I've bled these things to death but the rear always feels squishier than the front. I've also got m6000 mt500 and mt400 on other bikes, bled the exact same way and they're consistent. I've tried top down, bottom up bleeds, I've also tried lever depressed during final top off and sucking fluid through the caliper. Nothing seems to be helping.

Also once you adjust the reach the problem becomes more pronounced. At full extension it is only subtle.

I've almost given up these brakes. Tempted to change them out.
Is the freestroke adjusted the same on both? Was the freestroke out or in when you bled?
 

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Even after a perfect bleed, the much longer hose to a rear brake will always make it feel squishier (all else equal) as the hose expands slightly when pressurized. Some hoses are a bit better than others.
 

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I've never had an inconsistent front/rear feel with XT's (M8000) unless the free stroke was different at the levers.
 

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Discussion Starter · #8 ·
Even after a perfect bleed, the much longer hose to a rear brake will always make it feel squishier (all else equal) as the hose expands slightly when pressurized. Some hoses are a bit better than others.
Sure but then why are the three other bikes consistent front to rear? The deore uses the same hose as the xt ... Bh90. The other two use bh59.

Also my guide r feels the same front to rear also.
 

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Discussion Starter · #9 ·
I've never had an inconsistent front/rear feel with XT's (M8000) unless the free stroke was different at the levers.
Maybe I have a bung lever then? Like I said the shorter I adjust the reach after bleeding the more inconsistent it gets. With my hand side, it means they're either within reach but unusable or out of reach but more consistent.
 

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Swap the calipers from front to back. IME the problems with XT M8000 have been problems with the caliper. See if the problem follows the caliper or stays with the rear brake circuit.

If it stays with the rear, don't rule out problems of alignment on the post mounts at the rear.
 

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Discussion Starter · #13 ·
I did read that, kinda disappointing. Funny that it seems to be less of an issue on the cheaper sets though.

Tried re-bleeding, checked for leaks still the same.

I've decided to try out some Magura MT Trail Sports. Can't be stuffed wasting time on these XTs any more.
 

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I had consistency issues on my rear brake. Turned out the adapter I was using was too long and the top of the pads were slightly above the rotor. Pads were hanging on the top of the rotor causing the issue. Sanded the pads level and changed to the proper adapter. Fixed.
 

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Sure but then why are the three other bikes consistent front to rear? ....
I've worked on many brands and models of brakes and have always found the rear lever to be softer than the front all else equal. All plastic hoses expand under pressure, and a longer hose will make the lever softer. The degree of softness will depend on how elastic the hose is and the operating pressure of the brakes.
 

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achiever
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Yeah freestroke would all the way in and reach all the way out on both of them.
You want the free stroke screw all the way out when you're bleeding these, to the best of my knowledge. My XT's are pretty close but as mentioned above, the hose to the rear is a lot longer & will have more give than th front. I adjust both reach knobs til I get an even feel. They're pretty darn close as far as the reach goes, I can't tell the difference. Also, are your pads worn the same amount? That could have something to do with it.
 

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Discussion Starter · #17 ·
I've tried it both ways, free stroke in and out, free stroke out seems to help a little. I also a spent about 30 minutes doing the bleed at the lever after a bottom up bleed and it took 30 minutes to stop the tiny bubbles surfacing (I thought that was odd considering I'd just done the bottom up with no sign of bubbles). I then replaced the wheel and did another quick bleed to try take up the slack from the slightly worn pads. It's acceptable to use now but still unacceptable for a brands 'higher tier' brake system. If the mt500 and deore brakes can feel consistent I don't understand why it's so hard with the xt. Perhaps they do operate at a higher pressure but if the trade-off is consistent lever feel I still think that's not really acceptable at this level.
 

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RAKC
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I've always noticed this on all brakes I've ridden. Some a tad more than others. Shimano lower tier actually have less of a difference in feel than slx and xt. But of course slx/xt have more stopping power.

You said you had a major issue getting bubbles out which to me sounds like there is a fitting that's allowing a bit of air in. Have seen it accross Shimano tiers where the line at the lever isn't sealed correctly or crap in the washers at the fitting for the caliper. Go back and check all of that. It does happen sometimes. Both at the factory or when your running the hoses.

Sent from my SM-G950U using Tapatalk
 

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crembz;14221931I said:
also a spent about 30 minutes doing the bleed at the lever after a bottom up bleed and it took 30 minutes to stop the tiny bubbles surfacing (I thought that was odd considering I'd just done the bottom up with no sign of bubbles).
That is odd. Takes me about 25 minutes to bleed both sets of my XTs.

crembz;14221931I said:
I then replaced the wheel and did another quick bleed to try take up the slack from the slightly worn pads.
Are you removing the pads and using a bleed block?
 

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Discussion Starter · #20 ·
Yeah removing pads, using a bleed block, bottom up bleed with syringe, bleed bag, close the caliper, lever bleed, flick away at different angles with reach and free stroke adjusted out.

Then I close the caliper, reinstall the pads and wheel, squeeze a few times to set the pads and rebleed the lever.

Like I said they are acceptable now, but imo xt should be more than acceptable.
 
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