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View Full Version : Avid Elixir 5 on SJ FSR - Brake lever and piston question



markgrise
October 5th, 2012, 03:15 PM
I just picked up a brand new 2013 Specialized Stumpjumper FSR and the right rear brake lever doesn't have any play. The discs aren't rubbing, but the visual gap is much more narrow than the front lever which has a visible gap between the pad and rotor. The pistons were pushed back with a screwdriver, but that hasn't fixed the problem. I don't know where to begin. I have changed an entire braking system on a car, but I don't know much about these systems. How do you generally get the brake piston to sit farther back to allow for more clearance between the pad and the rotor (as well as more play in the lever itself)?

Incidentally, the brake lever also seems to have like a "pop in and pop out" mechanism. I can pull the lever opposite of the handlebar it's like it's popping out but when you pull the lever, it locks in to a closer position to the handlebar itself. It's strange.

Has anyone else experienced this before?

chickenshiet
October 6th, 2012, 11:20 PM
Adjust the lever reach adjust knob on the lever. Next Avid has a rep for bad factory bleeds. Take it back to the store. Or buy an avid bleed kit and bleed. Turn the knob on the good brake to determine which way loosens the pads. Turn the bad brake knob this way. Take the wheel off. These brakes come with a plastic spreader tool or use something less brutal than a screw driver like 2 butter[not table} knives to spread the pads.
Remount wheel, loosen caliper and center caliper slot on the disk.Tighten caliper and place a business card between each pad and disk if they fit. Clap down of the lever and loosen the bolts. Let up on lever then clap down and snug up the bolts. Release lever and tighten bolts. Check to see if the caliper is still fairly centered. Play around with the lever reach knob to see what it does. This is off the top of my head so go to the Sram website to get the tech manual.

markgrise
October 7th, 2012, 12:20 AM
Thanks for the advice. You're probably right; it probably needs bled. Kinda pisses me off on a brand new rig. I heard the SRAM stuff has had some issues. The brakes function, just not the right way. It's weird, though. It's got like a "lock" position where it stays outward, then as soon as you gently pull the lever, it recesses back to a position closer to the handlebar. I'm not sure if bleeding the system would eradicate the brake lever from sticking? Have you had this issue before?

Niner29er
October 7th, 2012, 05:39 AM
that, "staying out" thing with the lever is nothing. without seeing it in person I believe it is the same as my older style avid ultimate brakes. (which have about 15,000 miles on them with no major issues) make sure you are not stressing yourself out with this by over-thinking it! :confused: BTW, what area of the state are you in? myself or others would most likely be happy to inspect!

markgrise
October 7th, 2012, 08:19 AM
I guess I don't mind the issue of the lever locking in and out, but there has to be a way to create more play in the brake lever.

I'm in Columbus, OH. Any advice would be much appreciated. Thanks man.

Niner29er
October 7th, 2012, 08:31 AM
I am in Parma, by Cleveland. (and the royalview trail) I am a hands on kind of guy so I really can't say what is up. I will tell you that I have spent hours on some of my bikes because I LOVE brakes when they work perfect. (and can't sleep when they are not)

Mark Sullivan
October 7th, 2012, 05:11 PM
Adjust the lever reach adjust knob on the lever. Next Avid has a rep for bad factory bleeds. Take it back to the store. Or buy an avid bleed kit and bleed. Turn the knob on the good brake to determine which way loosens the pads. Turn the bad brake knob this way. Take the wheel off. These brakes come with a plastic spreader tool or use something less brutal than a screw driver like 2 butter[not table} knives to spread the pads.
Remount wheel, loosen caliper and center caliper slot on the disk.Tighten caliper and place a business card between each pad and disk if they fit. Clap down of the lever and loosen the bolts. Let up on lever then clap down and snug up the bolts. Release lever and tighten bolts. Check to see if the caliper is still fairly centered. Play around with the lever reach knob to see what it does. This is off the top of my head so go to the Sram website to get the tech manual.

I had this problem with Elixer 3 brakes on a bike I just bought. I put a screw driver between the pads (I know this is not recommended but it worked for me) and twisted it to spread the pads/caliper pistons, as I slowly opened the bleeder valve. Quickly close the valve after you feel the pads are not spreading anymore. Wrap a rag around the calipers in such a way to prevent fluid from getting on the pads before you do this.

bullitboy105
October 7th, 2012, 09:07 PM
I had this problem with Elixer 3 brakes on a bike I just bought. I put a screw driver between the pads (I know this is not recommended but it worked for me) and twisted it to spread the pads/caliper pistons, as I slowly opened the bleeder valve. Quickly close the valve after you feel the pads are not spreading anymore. Wrap a rag around the calipers in such a way to prevent fluid from getting on the pads before you do this.

Ideally the system should be bled. In a pinch, this method can be a decent way to circumvent bleeding (though be aware, can introduce air into the system). I'd generally open up the bleed port at the brake lever, rather than the one at the caliper to ensure any air that may enter the system is at the TOP of the lines, not the bottom. Avid does have some known issues with overfilling systems with the factory bleed - hence the 'tight' feel to the brake lever. If its not too bad though, just get out and ride - the brakes will have a bit of a break in period, and I've found that many of my Avid's settle in pretty nicely without having to fuss with them.

markgrise
October 7th, 2012, 09:38 PM
All good advice. Based on the replies, it seems an avid bleed kit would be a worthwhile investment. I found a video sponsored by SRAM on YouTube regarding how to bleed the brakes. Toward the end of the video, the guy showed how to tailor the position of the brake lever according to the bleed/fill. Still doesn't explain the feature of being able to flip the lever outward, but perhaps this will go away with a proper bleed?

bullitboy105
October 7th, 2012, 10:02 PM
All good advice. Based on the replies, it seems an avid bleed kit would be a worthwhile investment. I found a video sponsored by SRAM on YouTube regarding how to bleed the brakes. Toward the end of the video, the guy showed how to tailor the position of the brake lever according to the bleed/fill. Still doesn't explain the feature of being able to flip the lever outward, but perhaps this will go away with a proper bleed?

The lever flipping out allows you to lock off the master cylinder. More a safeguard against blowing the piston in case of violent contact with the ground/tree/rock/riding buddy. On the bleed kit, I rarely use mine - though when you need it, you need it.

markgrise
October 7th, 2012, 11:08 PM
Is there a reason my front brake wouldn't have this feature?

bullitboy105
October 7th, 2012, 11:18 PM
Is there a reason my front brake wouldn't have this feature?

Odd...hydraulic levers are 'reversible' so front/rear or left/right should be a non-issue. Wondering if inconsistency between bleeds is a factor? Off the top of my head, I thought that little 'feature' was part of all Avid setups, but now you've got me wondering....

markgrise
October 17th, 2013, 11:16 AM
Here's an update. (Forgot I had this thread out there). The factory bleed was the cause. I bought a bleed kit and voila, it worked perfectly. Then I realized the single piston wasn't grabbing hard enough, so I upgraded to XO Trails with dual pistons and now it stops on a dime. I weigh 195lbs and ride fairly hard. Expensive upgrade but I'm very happy with the performance.

IAMCLOUS
October 17th, 2013, 12:21 PM
On my 5th set of avid elixirs in 5 years. Great customer service (always covered under warranty with prompting from my local lbs), terrible product. Best thing about the product, the replacements always come with new pads, never had to buy a set of pads yet, but lots and lots of cutting down new brake lines. My newest set have the dual pistons, so I am once again hoping for the best.

markgrise
October 17th, 2013, 06:20 PM
Which did you get? All SRAM "trail" version sets now come with a four piston caliper. The dual piston wasn't enough. I don't think manufacturers accounted for how much harder it would be to stop a 29 inch vs 26 inch wheel. To be fair, the dual pistons worked, but they didn't stop fast enough going downhill.

IAMCLOUS
October 17th, 2013, 09:26 PM
It is the new trail 7 on the bike now....so two pistons per caliper side. It never has been a question of power for me, just getting the pistons to go back into their bore on a reliable schedule. Not cool to see me at the trailhead carrying a white sheet of paper to put below the brakes when dialing it in before every ride with the hopes of seeing a bit of daylight on both sides. And yes all prior versions were bled and rebled, tried new calipers, levers, etc.....

markgrise
October 18th, 2013, 09:35 AM
That's interesting. I wonder if heat build up caused the pistons to stick? It happens to cars all the time.

trainwreck
October 18th, 2013, 10:11 AM
i hate all avid hydro brakes went back to their mechanicals cause i could never get consistent pad clearance on the hydros.

side note since you mentioned car brakes...does anyone know what the little rubber bumper is on the end of one of the guide pins per each disc caliper is for? from my observation it is this thing that tends to swell over time and hang up the calipers causing pad heating and uneven wear.

IAMCLOUS
October 18th, 2013, 10:54 PM
My guess is not heat, but poor design. The pistons get gunked up from sand/water/mud and simply drag all that stuff back into the bores. As it becomes more difficult for the pistons to fit back where they are supposed to be, it leads to more of the piston sticking out. This excess "side piston" sticking out gets more gunked up. Eventually the rider gets upset and tried to push the piston back into the bores with force (be it by using credit card piles, factory supplied spreader, screwdriver) and the problematic gunk gets even further into the system. If you want to take the time to clean it up and drizzle some brake fluid on the pistons you might get it to work well for a while, but only that long. XT brakes on the other hand seem to make most people happy, rare to hear a complaint from folks I know...

rupps5
October 20th, 2013, 07:41 AM
I have the old 4 piston xt brakes and never had a problem with them and they were used on my downtown bike for years, now they are on my fs bike and still working great.

Heard from many people about the current xt being the best brake out there for durability, weight, and power together.

Right now I am trying out a set of 985xtr brakes I picked up used. only have one ride on them so can not give a review yet.

My go to brake is t the bb7. I have been riding these since they came out and probably have 5 sets of them and they are freekn great.