Cant get front rotor to stop dragging

SFellure33
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SFellure33
2021 YZ 450. Got cross jumped at an areacross last week and took a goo digger. Bent up the front of my bike pretty good(bars, mounts, etc.). I took everything off from the triple clamps down to the front wheel and put it all back together. Now my front brake WILL NOT STOP DRAGGING. I tried putting a different rotor on that I know isnt bent and that didnt fix the issue. Also, there does not seem to be any debris behind/around the caliper pistons that isnt allowing them to close all the way.

Any suggestions will be helpful.
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FarleyMX25
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FarleyMX25 1/4/2022 6:54am
1/4/2022 6:54am
Make sure the caliper sliders are clean and greased. It’s possible they may be packed full of dirt and not letting the caliper float.
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Moto520
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Moto520 1/4/2022 7:33am
1/4/2022 7:33am
They do drag a bit anyways.....how much different is the dragging than from before your crash?
SFellure33
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SFellure33 1/4/2022 11:27am
1/4/2022 11:27am
FarleyMX25 wrote:
Make sure the caliper sliders are clean and greased. It’s possible they may be packed full of dirt and not letting the caliper float.
Everything is as clean as possible. I literally took apart everything from the triple clams down. I couldnt find any dirt packed before or after I disassembled and reassembled everything.
SFellure33
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SFellure33 1/4/2022 11:32am
1/4/2022 11:32am
Moto520 wrote:
They do drag a bit anyways.....how much different is the dragging than from before your crash?
I know they always have a little bit of drag, but this is a significant change. Im only getting 1-2 seconds of free spin compared to 5-6 before the crash. Ive checked the rotor, wheel bearings, spokes, rim, caliper pins, pads, pistions, fork lug position, ect.

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FGR01
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FGR01 1/4/2022 11:47am
1/4/2022 11:47am
Very likely the caliper bracket itself is bent. Try one from a different bike.

Also, I've seen the mounting lugs on the fork get bent too, but this is less common.
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Paw Paw 271
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Paw Paw 271 1/4/2022 1:52pm
1/4/2022 1:52pm
The slide pin could be very slightly bent causing to drag and not allow the cal to return fully to open position.
Also there should not be any drag on the break. Ant drag indicates there is a problem. Also have too much fluid in the master will not allow the cal to fully release and thus cause drag.

Paw Paw
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sandhills
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sandhills 1/4/2022 2:00pm
1/4/2022 2:00pm
SFellure33 wrote:
I know they always have a little bit of drag, but this is a significant change. Im only getting 1-2 seconds of free spin compared to...
I know they always have a little bit of drag, but this is a significant change. Im only getting 1-2 seconds of free spin compared to 5-6 before the crash. Ive checked the rotor, wheel bearings, spokes, rim, caliper pins, pads, pistions, fork lug position, ect.
I think 5-6 seconds is only when the pads are broken into the rotor perfectly. Change anything or even just disassemble and reassemble and 1-2 seconds is normal.

Try riding it a bit like that then see how it is after.
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harescrambled 1/4/2022 5:04pm
1/4/2022 5:04pm
SFellure33 wrote:
I know they always have a little bit of drag, but this is a significant change. Im only getting 1-2 seconds of free spin compared to...
I know they always have a little bit of drag, but this is a significant change. Im only getting 1-2 seconds of free spin compared to 5-6 before the crash. Ive checked the rotor, wheel bearings, spokes, rim, caliper pins, pads, pistions, fork lug position, ect.
sandhills wrote:
I think 5-6 seconds is only when the pads are broken into the rotor perfectly. Change anything or even just disassemble and reassemble and 1-2 seconds...
I think 5-6 seconds is only when the pads are broken into the rotor perfectly. Change anything or even just disassemble and reassemble and 1-2 seconds is normal.

Try riding it a bit like that then see how it is after.
Good suggestion. If this makes no difference I'd have to suggest checking the front axle runout, and the fork tube runout (both upper and lower tubes).
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SFellure33
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SFellure33 1/5/2022 7:10am
1/5/2022 7:10am
I appreciate everyones thoughts and suggestions. I worked on it a bit more yesterday, disassembled everything again, checked and cleaned everything, put it all back together and its the same thing. Something has to be bent and Im thinking it might be the caliper bracket. That was the point of contact when they guy hit me, so it may have a slight bend in it that I just cant see with the naked eye.

It is ridable the way that it is, but I had just picked this bike up. I traded in my 2019 for this new 2021 and have about 5 hours on it total and thene this happens. Its really just bothering me that I cant get it figured out!
Moto520
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Moto520 1/5/2022 7:34am
1/5/2022 7:34am
put up a video of this. I'm still of the thought that it is all good. open up the brake pads a bit and spin the wheel. The wheel should spin free. now pump the brake.....show us what that looks like. I went through the same thing just to find out that there was nothing wrong.
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Rickyisms 1/9/2022 10:28am
1/9/2022 10:28am
Moto520 wrote:
put up a video of this. I'm still of the thought that it is all good. open up the brake pads a bit and spin the...
put up a video of this. I'm still of the thought that it is all good. open up the brake pads a bit and spin the wheel. The wheel should spin free. now pump the brake.....show us what that looks like. I went through the same thing just to find out that there was nothing wrong.
Same here. I swear every bike I’ve ever owned has done that.
casper
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casper 1/11/2022 3:15pm
1/11/2022 3:15pm
This might be a long shot but your front axle might be bent. Had this happen on my team's race bike for Baja after a previous crash. I tried everything I could think of, remounting the wheel, checking all the brackets, etc. and it still dragged where you could maybe get a 1-2 full rotations of the wheel before it stopped. We raced the bike anyway figuring it would loosen up over the race. When we finished, the front wheel was still dragging. When we got back to the US, we had our main mechanic look it over and he found the bent front axle. I would have never thought of checking the front axle, but it was the culprit of the brake dragging.
crpilot
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crpilot 1/14/2022 11:32am
1/14/2022 11:32am
I've had this before and found several issues (on different occasions) that FIXED the issue:
-Bent axle
-Bent brake flange (lower fork lug)
-Unevenly worn brake pads.
-Worn disc surface (not likely on a new 2021 but possible)
-Dirty caliper pistons that aren't allowing the pistons to retract properly
-Dirty or worn brake pin that doesn't allow the pad to move freely when brakes are released
-Air in the system or contaminated brake fluid

When all is in spec, it should not drag. With 280 hours of MX racing on my CRF, my front brakes spin feely. Its had proper maintenance and many parts replaced due to noted wear or damage.

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