Hope M4 Mono question

[vibiker]

I'm replacing the pads on one of my M4s.
I push the pistons back, but they don't stay back, thus causing the new pads to drag.
My guess is that there is too brake fluid in the system. Is this the most likely case?


If so, do I set up like I am bleeding, w/o adding any new fluid and drain from the caliper?

If not, HELP.

Thanks

[dG video]

I found when I replaced my pads that it was a very tight fit and took a little fiddling to get the wheel back in. Don't worry about it and ride them, they rbeak in nicely withing about 10 hrs of riding.

Dan

[Brian HCM#1]

Check the spacing and see it the rotor is center properly between the pads, also check to see if all the pistons are moving, sometimes it's as simple as stuck pistons.

[t66]

If your replacing some heavily worn pads you probably need to bleed out a little fluid. Try bleeding out a miniscule amount (1/2 drop). Should do the trick.
You could destroy a set of new pads trying to force the disc in between and the wheel probably won't turn anyhow.

[Brian HCM#1]

If your replacing some heavily worn pads you probably need to bleed out a little fluid. Try bleeding out a miniscule amount (1/2 drop). Should do the trick.
You could destroy a set of new pads trying to force the disc in between and the wheel probably won't turn anyhow.If the brake was properly bleed in the first place it shouldn't matter, even if the pads were completely fried.

[joelsman]

just take the top off the resivour and let some fluid drain out, this will let the pistons go back further, your system could under pressure if you added fluid with worn pads.

[Internal14]

If the brake was properly bleed in the first place it shouldn't matter, even if the pads were completely fried.

could matter if in fact the brakes were recently refilled/bled with some very used pads.
Then you'd have the pistons sticking out a touch with the system full of fluid. And when he installs the new thicker pads there's no place for the oil to go when he tries to push the pistons into get clearance for the now thicker pads.


I'd recommend pulling off the master cyclinder cap and wrapping a wrag under the resevoir and pushing the pads back in to full resting position.

Then while you're at it, flush the system and refill with fresh juice.

[Freeride4ever27]

could matter if in fact the brakes were recently refilled/bled with some very used pads.
Then you'd have the pistons sticking out a touch with the system full of fluid. And when he installs the new thicker pads there's no place for the oil to go when he tries to push the pistons into get clearance for the now thicker pads.


I'd recommend pulling off the master cyclinder cap and wrapping a wrag under the resevoir and pushing the pads back in to full resting position.

Then while you're at it, flush the system and refill with fresh juice.


But having the pads be thinner should have nothing to do with the pistons not retracting. You're right about the pistons being pushed more but they should still retract fine.

[Brian HCM#1]

could matter if in fact the brakes were recently refilled/bled with some very used pads.
Then you'd have the pistons sticking out a touch with the system full of fluid. And when he installs the new thicker pads there's no place for the oil to go when he tries to push the pistons into get clearance for the now thicker pads.


I'd recommend pulling off the master cyclinder cap and wrapping a wrag under the resevoir and pushing the pads back in to full resting position.

Then while you're at it, flush the system and refill with fresh juice.Not true, when you're bleeding Hopes the pistons should be pushed back ALL the way flush/maxed with the caliper. When the system is fully bleed and capped off you pump the lever to set the pads, the amount of fluid is the same weather there are new pads or fried pads installed.

[vibiker]

Just an update. I exercised the pistons and made sure that each one was moving freely.

Then retracted all 4 pistons, popped in the pads,installed the wheel, and now the wheel spins like a charm with no drag.:dancing:

Thanks guys. :thumb: