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  1. #1
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    Juicy 7 Rotor rubbing calliper/adapter

    I just switched from a 165mm to a 185mm rotor on my front brake and the new rotor is rubbing on the adapter which attaches the caliper to the fork. My set up is a Talas Fork, WTB Laser Disc Lite Hubs and the Juicy brakes.

    I am guessing that some of the possible problems could be:
    1. my disc tabs on the fork are out of allignment
    2. bad mounting adapter,
    3. problem with the hub?

    Thought I would see if any body had come accross a similiar problem and any suggestions.

    I have attached a few pictures (sorry for the poor quality)
    Attached Images Attached Images

  2. #2
    Riding free's the mind
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    Hmm?

    Don't get it- I have Juicy's and the cps bolt is a good 1-2mm away from the rotor. I thought this bolt (where you show rubbing) follows the caliper- in other words this distance is fixed?

    The other possibility is, and not sure if I'm seeing it right in your photo, but it looks like your rotor is biased to one side inside the caliper- as if one pad is stuck in a bit? The rotor should be pretty much running through the caliper centered in the slot.

    Maybe a bleed is in order? I bleed mine and discovered some air in the line and the hydraulic fluid level a little low.
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  3. #3
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    You're right HTail, there's another problem here.

    The rotor should be centered in the caliper slot. If you grab the lever to adjust the CPS bolts, and the rotor doesn't center up, then you have a stuck piston or something.

    String, check out what's going on with that.

  4. #4
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    may have been stuck piston, but still not much clearance

    Thanks, I think it might have been a stuck piston. The inside (closest to the wheel) piston was sticking out a little. I pushed it back in and that seemed to help. The clearance is still pretty tight, maybe 1mm at most between the CPS bolts and the rotor but the rotor seems to run parallel with the pads and does not touch the bolts (at least on the repair stand). I guess the piston was pushing the rotor towards the bolts causing them to rub.

    I still wish I had a little more clearance, but I'll see if this is enough. My rear rotor (a 165mm not a 185mm) has a good 2-3mm clearance which makes me think the front should have a little more but I'm not sure.

  5. #5
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    Quote Originally Posted by string
    Thanks, I think it might have been a stuck piston. The inside (closest to the wheel) piston was sticking out a little. I pushed it back in and that seemed to help. The clearance is still pretty tight, maybe 1mm at most between the CPS bolts and the rotor but the rotor seems to run parallel with the pads and does not touch the bolts (at least on the repair stand). I guess the piston was pushing the rotor towards the bolts causing them to rub.

    I still wish I had a little more clearance, but I'll see if this is enough. My rear rotor (a 165mm not a 185mm) has a good 2-3mm clearance which makes me think the front should have a little more but I'm not sure.
    Yes it should have more. Are you saying that there's no more room for the caliper to slide outwards on the CPS bolts?

    If so, then I'd have your tabs faced.

  6. #6
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    Thats correct. The caliper is slid all the way out away from the wheel. Sounds like I need to get the tabs faced. Hopefully, my LBS has the tools to do it. I guess if not, I can rent the tool from Hammerhead Bikes and have them mail it if they still do that.

  7. #7
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    This is one of those instances of poor tolerancing. Not sure if it is your hub or the Fox, but I have seen this problem. I think some of the older fox lowers were a bit too close causing the rotor to sit right against the washers. This issue has been posted with fox and several hubs (chris king, hugi 240, your hub). Unfortunately the only solutions require machining of the hub or the fork tabs for additional clearance. I would take it in to your LBS and have them contact fox about warranty first. If the shop has a disc tab facing tool they may be able to take off 1-2mm for clearance, but I would try warranty first.

  8. #8
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    I am going to have my local shop look at it in the next week or so (they can't look at it till late next week). I am hoping they can face it, becuase I think 1-2mm is all I need. Unfortunatly, I did not buy the fork from my local shop and I doubt they deal with fox often. I actually order all the parts (fork, hub, and brake) from Larry Mettler so if I can not fix it locally, I may get him to help. (I may have to run the 6" rotor till a any rainy spell and then send it in)

  9. #9
    Riding free's the mind
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    One pad out more than other

    I was just on a lunch ride today and both myself and friend have Juicys. Noticed on both of our brakes, one pad does stay out more than the other.

    Now mine was much more apparent, part of this might be due to my last bleed job where I think I over-pressurized the fluid reservoir (something not in the bleed instructions). Honestly I'm still rather new to hydro brakes, so learning as I go along here.

    Even with this one pad out further, the only downside is the pad scrapes the rotor- annoying! Clearance is still fine.
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  10. #10
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    Quote Originally Posted by HTail
    I was just on a lunch ride today and both myself and friend have Juicys. Noticed on both of our brakes, one pad does stay out more than the other.

    Now mine was much more apparent, part of this might be due to my last bleed job where I think I over-pressurized the fluid reservoir (something not in the bleed instructions). Honestly I'm still rather new to hydro brakes, so learning as I go along here.

    Even with this one pad out further, the only downside is the pad scrapes the rotor- annoying! Clearance is still fine.
    I was fiddling my my brake again this evening and noticed the same thing. My inside (closest to tire) pad sticks out a little more. I pulled the pad, pushed in the piston, reinstalled everything and noticted the first time I pulled the lever it was very mushy. The pad went out, stayed slightly out, and the lever firmed up. I've only been on discs for about 8 months so this may be due to a poor bleed job as well. I am going to try to rebleed this weekend.

    I did manage to get another 1/2mm or so in clearance with the bolts. Pad clearance was tight but OK. I was hoping to test ride this weekend, but looks like its going to rain (Tropical storm Ivan is coming through tonight).

  11. #11
    Amphibious Technologies
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    Face the Adapter or the brake mounts

    I've had a similar problem with 205mm rotor Avid Mech before. ('03 Z1 fork, QR King hubs) Solved it by facing the adapter with a file at the portion where the adapter meets the brake mount on the fork. Alternatively you can face the brake mount on the fork with a facing tool such as the Hope Spot Disc Mount Facing Tool

    Follow link below, click on Maintenance Products and click on Spot Disc Mount Facing Tool

    http://www.hopetech.com/products/products_index.htm

  12. #12
    theHeadlessThompsonGunner
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    A friend of mine had to face the bejesus out of his Talas disc tab to get his Hayes Mag Plus to fit - I'd guess that your problem is similar. I'd go find someone with a good, sharp tab-facer and go wild with it.
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  13. #13
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    Quote Originally Posted by SDizzle
    I'd go find someone with a good, sharp tab-facer and go wild with it.
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  14. #14
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    Thats what it looks like I am going to have to do. Now I hope I can find a shop with a tab-facer locally, they get expensive to buy.

    I put my 6" rotor back on for the time being since it has enough clearance. I still think its a little strange that the 6" has enough clearance but when I move up to the 7" it does not clear.

    I did notice one of my pistons is still sticking a little. I can push it in, but the 1st time I hit the lever it stays out around 1mm. The brakes work fine after fine though so I am guessing its not a major issue, just a pain in the a$$. I rebled the brakes this weekend, but did not fix the sticking piston..

  15. #15
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    And I thought it was just me who had this problem. I have the same setup and the same problem. I find that if I crank down my QR lever that I can't even move the rotor. What I'm doing now is keeping my QR just tight enough to keep the wheel on. This gives me about 2mm of clearance. Not nearly what it should be but it works.

  16. #16
    "El Whatever"
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    Quote Originally Posted by woodyak
    And I thought it was just me who had this problem. I have the same setup and the same problem. I find that if I crank down my QR lever that I can't even move the rotor. What I'm doing now is keeping my QR just tight enough to keep the wheel on. This gives me about 2mm of clearance. Not nearly what it should be but it works.
    Flexy axle??? I know the Shitmano Deore front hub likes to bend (and crack also) its axle. Axle diameter is smaller than a LX and XT for instance. This makes for funny disc brake adjustments.

    I couldn't tell of the WTB's Lasers thou. But if you notice that the QR is "helping", then your axle might be flexing a lot. Pull it our and take a look at it. It could be a bit bent.

    The fork dropouts are supposed to remain separated at 100mm by the axle (bearings/cones locknuts). If by tightening your QR you can get the dropouts (along with the brake tabs and anything attached to them, including adaptors, calipers, squirrels) closer to the rotor (which is fixed to the hub) then the only thing that could be happening is that your axle is bending and thus allowing the fork dropouts to get closer between them.

    Not only that, a flexy axle can lead to increase the stiction at the fork. If the axle allows the distance between both dropout to go lower than it should be the fork's stanchions will not move freely into the bottles causing more stiction and eventually an excessive wear on bushings.
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