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Discussion Starter · #1 ·
Is there a way to adjust the modulation on Avid Elixirs? The brakes work great, but it seems they are a bit touch sensitive (pull the lever just the slightest bit too far and they lock up on looser terrain)?

Also the rear brake drags a bit. I readjusted the allignment an got the wheel to freely rotate, but after the next ride, they need readjustment. Any suggestions?
 

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Old man on a bike
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There's no modulation adjustment other than trying a bleed and see if that might tweak it...as to your caliper realignment, what happened after that, what's causing the rubbing now? Did it come misaligned again or is your rotor warped or what? You gotta do some analysis...
 

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Discussion Starter · #3 ·
Thanks for the reply...will try the bleed for modulation.

The brakes are only a few weeks old and starting from the initial installation, it has been extremely difficult to eliminate the rubbing, even before the bike was ridden. The rotor is not warped as far as I can tell. I believe it has become misaligned of the course of 4-5 rides. Seems like the tolerance is so tight that there is no room for error.

The front alignment worked the first time and I've had no rubbing issues at all since the initial installation.

Is there a method to increase clearance between the pads and rotors? i've looked at all of the Avid literature (i believe) and have found nothing on the subject.
 

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scolli said:
Thanks for the reply...will try the bleed for modulation.

The brakes are only a few weeks old and starting from the initial installation, it has been extremely difficult to eliminate the rubbing, even before the bike was ridden. The rotor is not warped as far as I can tell. I believe it has become misaligned of the course of 4-5 rides. Seems like the tolerance is so tight that there is no room for error.

The front alignment worked the first time and I've had no rubbing issues at all since the initial installation.

Is there a method to increase clearance between the pads and rotors? i've looked at all of the Avid literature (i believe) and have found nothing on the subject.
How are you checking for a warp in the rotor? If it's just rubbing at certain points in the disc's revolution it's likely a bit of warp. If it's rubbing constantly, is it the inboard pad it constantly it rubs against? The outboard? What might you be able to tweak to allow it to sit over the disc better? CPS doesn't do everything, especially if you need to have your caliper at the limits of it's adjustment range. That sort of thing, it's hard to tell from your description what specifically you might try...can't see what you're looking at.
 

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Rollin 29s
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Modulation is something you will just get used to, and the brakes will modulate better after several rides.

My first ride out on my Elixr CRs, the front wheel locked up throwing me over the bars and I fractured a rib and my left wrist. I had been riding a Shimano XT front disc before that and it modulates much better. However, I moved the Elixr levers in on the bars for 1 finger braking and learned to use them lightly and no problems since.
 

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Discussion Starter · #6 ·
I will take a closer look at it in the morning (I see better in daylight) and try to determine exactly what is going on.

Thanks for the help
 

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Discussion Starter · #7 ·
Bikinfoolferlife said:
How are you checking for a warp in the rotor? If it's just rubbing at certain points in the disc's revolution it's likely a bit of warp. If it's rubbing constantly, is it the inboard pad it constantly it rubs against? The outboard? What might you be able to tweak to allow it to sit over the disc better? CPS doesn't do everything, especially if you need to have your caliper at the limits of it's adjustment range. That sort of thing, it's hard to tell from your description what specifically you might try...can't see what you're looking at.
It is the inboard pad. I readjusted yesterday and was able to eliminate the rub, but it took several attempts because the inboard pad is so close and there is no room for error. I don't expect it to stay put on my next ride. I also bleed a couple of drops of fluid from the rear. What is weird, is that I can actually see light and plenty of clearance between the pads/rotor on my front brake...but not on the rear ones.

I also, pulled the caliper, removed the pads and noticed that the inboard piston barely moves (maybe 1mm) in comparison to the outboard. Is this normal?.

I may just have to live with the rubbing or readjust frequently. :rolleyes:

Thanks
 

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scolli said:
It is the inboard pad. I readjusted yesterday and was able to eliminate the rub, but it took several attempts because the inboard pad is so close and there is no room for error. I don't expect it to stay put on my next ride. I also bleed a couple of drops of fluid from the rear. What is weird, is that I can actually see light and plenty of clearance between the pads/rotor on my front brake...but not on the rear ones.

I also, pulled the caliper, removed the pads and noticed that the inboard piston barely moves (maybe 1mm) in comparison to the outboard. Is this normal?.

I may just have to live with the rubbing or readjust frequently. :rolleyes:

Thanks
It'd be nice if someone designed a hydraulic brake that actually had pad adjustment. Maybe you could free up the piston if it's just sticky, they should move equally; maybe you have a warranty issue. Are you able to get the rear caliper pads an equal distance from the disc otherwise?
 

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Discussion Starter · #9 ·
Bikinfoolferlife said:
It'd be nice if someone designed a hydraulic brake that actually had pad adjustment. Maybe you could free up the piston if it's just sticky, they should move equally; maybe you have a warranty issue. Are you able to get the rear caliper pads an equal distance from the disc otherwise?
I agree, manual pad adjustment would be nice....never used hyd brakes before and just assumed some type of manual adjustment would be included like on mechanical brakes (if you don't like the clearance on mechs, just tweek the cable tension...done).

I am going to remove the front caliper/pads tomorrow and see of the piston behavior is the same as the rear.

Thanks again
 

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Dirt Deviant
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Sounds like the rear may have a bit too much fluid in the system.
The way to take care of that is to push the extra fluid out.
It's really easy but it helps if you have 2 people.
The way I do it is to take the wheel off.
Insert a clean flat bladed screwdriver between the pads, bigger blade works better IME,
Have buddy remove bleed plug at lever and hold a rag under the hole.
While the bleed plug is out, carefully and slowly twist the screwdriver between the pads, spreading them to the stock position,
While maintaining pressure on the pads with the screwdriver, have said buddy put the bleed plug back in and snug it up.
The excess fluid will be pushed out of the system and there will be more clearance between the pads.
After doing this, realign the brake caliper if needed.
This may also help the sticky piston.
 

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I'm actually having the opposite problem with Elixir R's. My front brake is fine, well not as strong as yours sound but I can deal with that but my rear pads take ages to grip the wheel. I pretty much have to use all lever movement to get good braking.

Do you think adding more brake fluid using a similiar method to what savagemann posted would fix it?

sorry for the thread hijack!
 

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Discussion Starter · #13 ·
SavageMann suggested bleeding some fluid in my case, so i reckon adding some might help with your case (but harder to do than my case). Also, tinker with your pad contact adjustment on the levers (if you have them).
 

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El Baron said:
I'm actually having the opposite problem with Elixir R's. My front brake is fine, well not as strong as yours sound but I can deal with that but my rear pads take ages to grip the wheel. I pretty much have to use all lever movement to get good braking.

Do you think adding more brake fluid using a similiar method to what savagemann posted would fix it?

sorry for the thread hijack!
Sort of the same deal, but you need to do a bleed.
Same process of spreading the pads, but then you need to bleed the brake per the avid instructions.
That should tighten the reach up.
 

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savagemann said:
Sort of the same deal, but you need to do a bleed.
Same process of spreading the pads, but then you need to bleed the brake per the avid instructions.
That should tighten the reach up.
Make sure you use the bleed blocks included with the kit. If you bleed them without the blocks, the pistons will be too far out and make the issue worse. The flipside to this is that if you use the bleed blocks and them 'shim' them on either side with pieces of aluminum from a pop/beer can or an appropriate feeler gauge (business cards should work too) , you will effectively have a little more clearance and better modulation. I set my Elixir CRs up this way and it worked wonders. I also found that when bleeding, it's easy to pull too hard on the siringe at the lever. Don't be a hero - just nice and steady pressure. I also found that originally bleeding a few drops out of the caliper helped tremendously as they were overfilled from the factory it seemed.

Good luck and please let us know.

Thanks,
A.
 

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Discussion Starter · #16 ·
Lots of good suggestions here...much appreciated.

I should have time to work on them some more later. I've already taken a couple of drops from the caliper, but haven't had time to evaluate results. :thumbsup:
 

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Discussion Starter · #17 · (Edited)
I found the attached pics in another post ( http://forums.mtbr.com/showthread.php?p=6325409#poststop ).

jabone said:
Ok, i don't think i fully understand the responses.

The lower piston from the picture sticks out about 1/4" from the base of the caliper. The upper piston from the picture sticks out about 1/16" from the base of the caliper. Is this normal? ...... This is what is causing some of my brake rub.
Thanks
The OP had the same issue I'm having (not exactly sure if he/she resolved it though :confused: ).

So now I believe the problem is that Avid's CPS alignment system cannot work properly if one piston's inward movement is substantially less than the other (the caliper unit will position itself more to one side and closer to the edge of the alignment cups during the alignment procedure). I just need to free the "stuck" caliper and realign. I will first try to lubricate with DOT fluid and work it in and out until I get more movement like others have suggested. In the mean time, Any other suggestions for freeing the piston would be much appreciated.

I'll let ya'll know the outcome.

Thanks
 

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Discussion Starter · #18 ·
OK, I believe I have solved the rubbing problem on the rear caliper...won't know until my next ride, but I was able to easily align the caliper. Here is what I did (can't remember who made the suggestion):

1. Removed the rear caliper and pads.

2. Made a little clamp device to hold the outboard piston in place while I lubricated (DOT fluid) and exercised the inboard piston via the lever. Then, I spread the pistons again and repeated until I got more inward travel from inboard piston.

3. Performed the alignment procedure a couple of times and Voila!

The rear now spins freely...hope it holds up!:thumbsup:

A big thank you to all for the recommendations.
 
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