Sram guide ultimate rubbing

Rowan404
Rowan404 Posts: 104
edited June 2018 in MTB workshop & tech
My guide ultimates won't stop rubbing. Rotors look perfectly straight. I've also tried all the techniques like loosening bolts and squeezing lever, pushing pistons back and just eyeing it. It seems like there just isn't enough space for between the pads. Funny how I've never had this problem with shimano. Anyways, any insight is appreciated.
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  • JBA
    JBA Posts: 2,852
    Have you tried releasing a couple of drops of fluid from the reservoir?
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  • cooldad
    cooldad Posts: 32,599
    Have you done anything to them or have they always rubbed (assuming new bike?)
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  • Rowan404
    Rowan404 Posts: 104
    cooldad wrote:
    Have you done anything to them or have they always rubbed (assuming new bike?)
    It's a used bike that I just got off someone. I'll try releasing some fluid but not sure if it'll help.
  • swod1
    swod1 Posts: 1,639
    On these brakes isn't there an adjustment screw or something on the lever for bite point maybe this is wound in too much causing the rubbing of pads on the disc?
  • jamski
    jamski Posts: 737
    swod1 wrote:
    On these brakes isn't there an adjustment screw or something on the lever for bite point maybe this is wound in too much causing the rubbing of pads on the disc?

    You mean reach adjustment?
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  • kajjal
    kajjal Posts: 3,380
    JBA wrote:
    Have you tried releasing a couple of drops of fluid from the reservoir?

    This is what I would try, had it on a couple of brand new bikes, they just put too much fluid in. Once corrected no more rubbing and brakes work well.
  • steve_sordy
    steve_sordy Posts: 2,446
    jamski wrote:
    swod1 wrote:
    On these brakes isn't there an adjustment screw or something on the lever for bite point maybe this is wound in too much causing the rubbing of pads on the disc?

    You mean reach adjustment?

    There will be reach adjustment, most non budget brakes have that. But the more upmarket brakes also have bite point adjustment. When I had Shimano XT brakes they had bite point adjust and I could never detect anything from one extreme to the other, so I left it with the screw fully in and ignored it from then on. But SRAM Ultimate may be different. It's worth a try as you most certainly have that facility.
  • Before you undo the grub screw to release some fluid, remove the pads and fiddle them back in with half a business (or similar) each side of the disc, between disc and pads. Then undo the grub screw. This should release a tiny bit more fluid.
  • steve_sordy
    steve_sordy Posts: 2,446
    Better still, if the pads are rubbing on one side only, put one business card on that side only. Then slacken the caliper bolts, firmly pull the brake lever and then tighten the caliper bolts a bit at a time on each side. This should move the caliper over to one side by the thickness of the business card. (Or use a piece cut from a cereal box).
  • swod1
    swod1 Posts: 1,639
    jamski wrote:
    swod1 wrote:
    On these brakes isn't there an adjustment screw or something on the lever for bite point maybe this is wound in too much causing the rubbing of pads on the disc?

    You mean reach adjustment?

    No on some high end brakes there is also bite point adjustment where you can move the pads in or out of the disc rotor.

    looking on https://www.sram.com/sram/mountain/prod ... mate#specs there is the reach adjustment on the lever but also like a dial wheel on the brake body. i think this is the bite point adjuster that moves the pads in or out.
  • Rowan404
    Rowan404 Posts: 104
    I don't think bite or reach will help with this problem as there is space in the lever pull until the brakes actually work. Also when I push the lever back nothing changes.
  • Rowan404
    Rowan404 Posts: 104
    Tried the business card strategy but it was still rubbing on one side. Seems like my only option left is to release fluid. How would one go about doing that?
  • swod1
    swod1 Posts: 1,639
    Rowan404 wrote:
    Tried the business card strategy but it was still rubbing on one side. Seems like my only option left is to release fluid. How would one go about doing that?

    You'll have to get a bleed kit and see if you can draw out a little fluid at the caliper end, not too sure as more experience with shimano brakes, that you can easily do it with the screw in funnel on to the lever body.
  • 02gf74
    02gf74 Posts: 1,168
    This may be like sram level brakes where there is no Bleed nipple but a recess into which the bleed widget fits, believe it is called bleeding edge..

    To release a small amount of fluid, pull on the lever e. G. Tie elastic bandy on it, use a 4 mm hex key to slightly undo insert then close it.

    I did this success full y on my brakes. You need the kit to bleed them, which you will need to do sometime so may as well buy.
  • Rowan404 wrote:
    Tried the business card strategy but it was still rubbing on one side. Seems like my only option left is to release fluid. How would one go about doing that?

    Just undo the grub screw on your brake lever. Do it when the cards are in between you pads and discs. Try to make sure you have your brake lever positioned so that the screw is at its highest point.
  • 02gf74
    02gf74 Posts: 1,168

    Just undo the grub screw on your brake lever. Do it when the cards are in between you pads and discs. Try to make sure you have your brake lever positioned so that the screw is at its highest point.

    I'm not sure that will work. Usually the bleed on the brake lever is for the reservoir and is before the pressurised system I. E. The part of the hydraulics that is before the piston, it's function is to top up the fluid as the volume in creases due to pad wear.
  • 02GF74 wrote:

    Just undo the grub screw on your brake lever. Do it when the cards are in between you pads and discs. Try to make sure you have your brake lever positioned so that the screw is at its highest point.

    I'm not sure that will work. Usually the bleed on the brake lever is for the reservoir and is before the pressurised system I. E. The part of the hydraulics that is before the piston, it's function is to top up the fluid as the volume in creases due to pad wear.

    Granted. It has never failed for me yet though. Have to admit my Guides are harder work than my Shimanos.
  • Rowan404
    Rowan404 Posts: 104
    Releasing fluid didn't really seem to change anything. If I adjust the caliper manually I can get them to a point where they don't rub but tightening the bolts or braking will just cause them to rub again. It doesn't affect braking performance in any way but it is quite loud and annoying.
  • 02gf74
    02gf74 Posts: 1,168
    I take it you released a small amount of fluid by opening the bleed screw at the calliper.

    Just checking and it is definitely the rotor rubbing on the pads,I tried using hope saw rotors with sram brakes and the hollow rivet contacted the calliper.


    Next step I guess is to fit new pads and brake Bleed.
    Is it one or both rubbing

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  • Rowan404
    Rowan404 Posts: 104
    It is for sure the pads that are rubbing and it's just the front. I have some more urgent matters to attend to but I'll probably get some new pads eventually. For now I'll just leave them be.
  • Rowan404
    Rowan404 Posts: 104
    Quick update, it turns out that it wasn't the pads but the metal thing in the middle that connects the pads. It was bent and sticking out. I tried bending it back to no avail. It seemed like whatever way I bent it, it would still be sticking out. Anyways, this doesn't really change anything because I still have to get a new set of pads. At least it will give me a chance to try sintered instead of organics.
  • 02gf74
    02gf74 Posts: 1,168
    Rowan404 wrote:
    the metal thing in the middle that connects the pads. .


    You mean the spring or the pin? The former usually comes with a set of pads..... But at least it looks like you've sorted it.
  • Rowan404
    Rowan404 Posts: 104
    02GF74 wrote:
    Rowan404 wrote:
    the metal thing in the middle that connects the pads. .


    Sorry, I'm not too familiar with mtb terminology. It was the spring, I could probably bend it back if I had more patience but I already ordered new pads out of frustration.
  • swod1
    swod1 Posts: 1,639
    spring retaining clip, you get a new one with new pads.

    Why do you want to try sinitered pads? those I've found to only use them in gritty conditions.

    I use uberbike semi metallic and found the wear rate to be very good and easy to bed in.
  • jamski
    jamski Posts: 737
    swod1 wrote:
    spring retaining clip, you get a new one with new pads.

    Why do you want to try sinitered pads? those I've found to only use them in gritty conditions.

    I use uberbike semi metallic and found the wear rate to be very good and easy to bed in.

    Off topic probably, but out of interest, why semi metallic over their race matrix? Looking at new pads and it's down to these two. :)
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  • swod1
    swod1 Posts: 1,639
    jamski wrote:
    Off topic probably, but out of interest, why semi metallic over their race matrix? Looking at new pads and it's down to these two. :)

    I'm using actually a combination of both, i'd forgotten a couple of months back semi metallic was out of stock so i have race matrix pads.

    I've got race matrix in front and semi metallic in the rear.

    Not had any issue with the pads in my front brake pretty good actually. i'll be fitting some to rear brake this weekend as the pads in there have got damaged due to a warped disc.
  • steve_sordy
    steve_sordy Posts: 2,446
    I have been ignoring my other bike for several months. Went out on it last week and whenever I stopped pedalling, there was a coarse musical note, like from a horn. It sounded to be coming from the front, but I've done enough noise hunting to know that is no guide at all. Annoying as it kept it up throughout the ride.

    Because it only happened when I stopped pedalling, I assumed that it must be limited to the drive train. Something that rubbed on something else when the gears and chain were not moving. I thought it might be the freehub, but tried other stuff before I started down that route!

    Long story short: It was the rear brake! Guide RS, not Ultimate. One of the pads was resting on the disc and stroking it into making the noise. Why it should only do it when I wasn't pedalling, I dunno. Maybe it was the frame distortion as I pedalled that upset the vibrations from building up in the disc? Anyway, I loosened the caliper body, applied the brake lever and re-tightened the caliper bolts. Daylight was now showing both sides of the disc. A test ride revealed that the problem was solved! :)
  • Rowan404
    Rowan404 Posts: 104
    swod1 wrote:
    spring retaining clip, you get a new one with new pads.

    Why do you want to try sinitered pads? those I've found to only use them in gritty conditions.

    I use uberbike semi metallic and found the wear rate to be very good and easy to bed in.
    To be honest the main reason I bought them was because I could get two day shipping on Amazon. Other than that I read that they do better on prolonged descents and in the wet. I got them just to try and if I don't like them I can always just use the spring on my old organic ones.
  • Rowan404
    Rowan404 Posts: 104
    So I fixed the spring problem but now I have another rubbing problem. I can adjust the caliper to not rub but after a ride or two it just goes back to rubbing creating an endless cycle of re-adjustment.
  • 02gf74
    02gf74 Posts: 1,168
    What parts are rubbing.?

    As you can see by the length of this thread, it is difficult to diagnose without seeing it or with incorrect information.