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-   -   Avid Juicy 5 brake drag! (https://www.bikeforums.net/bicycle-mechanics/457538-avid-juicy-5-brake-drag.html)

nikos 08-23-08 04:05 PM

Avid Juicy 5 brake drag!
 
Alright, Im very familiar with my BB7 brakes, but I have juicy 5s on my enduro and both the front and rear are too tight and drag on the rotors. Adjusting the calipers does nothing the pads are just too close. Also, the brake feel is to tight, the moment I engage the brake it starts braking, I would like more flex into the braking. No pad adjusters, do I need to bleed the lines to make this adjustment? Or is there an easier way? thanks,.

cascade168 08-23-08 04:26 PM

Is there no reach adjustment screw in the lever pivot post??? This may be your only problem. First, look into that. Usually, this is a 1.5 or 2.0mm allen screw that goes through the pivot on the brake lever. Usually, screwing this into the pivot post (i.e. clockwise) will move the engagement point of the brakes closer to the handlebar. Just be careful that you don't over do it. Small turns of that screw can make a big difference in the reach. Just go slow.

If not that, then you may need to align the calipers (may require shimming) or true the rotors.

It sounds to me that your problem is either one, or a combination of both, of the two issues I described.

Go to this doc:

http://www.sram.com/_media/techdocs/95-5013-109-000.pdf

and see step 7 for more exact infomation. This is the Juicy 5 .pdf

cascade168 08-23-08 04:35 PM

Another thought .....

Did you purchase the rotors at the same time as the brakes? You may have a mismatch there.

nubcake 08-23-08 06:30 PM

almost all rotors are the same thickness so that shouldnt be a problem. alot of times ive seen that people will acidentally pull the brake lever with the wheels off so first off i would try the simple approach and with a flat blade screwdriver push the brake pads/pistons into the caliper.

if that doesnt fix it check caliper alignment and that the wheels are straight in the drop outs

if that doesnt get it, bleed the brakes. and last i would check to see that the pistons are retracting when you let off of the brakes, avids have had issues at times with sticking calipers. If that ends up being the case call sram and there is a really good chance they will just send you a new caliper at the least, in my experience they have awesome customer service.

nikos 08-23-08 08:00 PM

yeah, I do have a serious sticky rear caliper - slow return. The front grab is tight and has a packed up feel on the handle, but not a slow return. Ill look into all the tips and report from there. Thanks,

BCRider 08-23-08 08:15 PM

There's a number of things that this could be. But it doesn't sound like a lever reach issue since you're saying that the brakes grab right away.

There may be too much fluid in the systems so that the pads can't retract far enough. If they were sticking and were bled while sticking closer to the disc then this may be the case. On the Hayes Mag systems this was very easy to do. Not sure about the Avids but it's worth a check. Also be sure your levers are coming back far enough that it opens up the little leak back hole into the reservoir area. If they don't and you don't have a way for the expanding fluid to get away it will seal the system and you've then got a closed system rather than a proper open one.

If the calipers are not sitting so that they are dead nuts square then they'll drag. This means both planes so angle and tilt have to be set. Thanks to the cup and ball washer setup Avid uses you can set the caliper so it's perfect in every way. However this can often be a very fussy business. Especially if one or more of the cup and ball washer pairs is a bit sticky.

Or it could be just the pads are sticking so they don't return all the way since you say you have slow to return pads. In addition to being slow they may not be moving back as far as they should. The full on way to fix this is a full strip and rebuild. The bandaid that MAY work is to take the caliper off, remove the pads and then hose the calipers down with some brake cleaner. Wear safety glasses and do this over a bucket. The stuff will splash all over the place and it stings the eyes something fierce. Now contrary to popular belief you CAN pump the lever while it's off the disc but you just need to be careful. One pump and then ensure it retracts fully. Then another pump and watch it retract. You'll need to do this as part of the cleaning to get the grunge out of the outer seal area. It's that buildup that's making your pistons sticky. Working the pistons will encourage that stuff to flush out. If need be push them back with a little scredriver or other tool. Just don't pump repeatedly or they WILL pop out and then you get to do that full strip and rebuild after all..... :D

nikos 08-24-08 12:57 PM

Alright so I pulled off the front caliper and the pads. Noticed while gently pulsing the brake that one of the pistons would keep pushing up and not retracting. Used some Dot 4 on the sides and gently pulsed the brake to settle the fluid in and around.....nothing. So what to do next? The one side works just fine, the other just keeps rising with no retraction - is this a common problem?

BCRider 08-24-08 06:45 PM

How old is this set? If it's been around a while it may be time to fully strip it and rebuild with new seals. As seals age they tighten their grip on the pistons and since our bicycles use such whimpy return springs it doesn't take much stiffening of the seals to overcome the springs.

And while you used fluid on them did you try blasting the gap with some brake cleaner? It doesn a pretty good job at softening and flushing out grunge. Better by far than brake fluid.

nikos 08-24-08 09:12 PM

didnt try brake cleaner, what brand/type should I be looking for at the auto shop. Also, if Im looking at a rebuild, would I be better off with new brakes all together. Noticed Mountain Bike UK had a nice write up on the Stroker V7 trail brakes. The Avids are from my 2005 Specialized Enduro.

ClayNichols 08-03-09 03:05 PM

When I adjusted the tiny hex/star screw, (hydraulic?) fluid came out. Why?
 
I made the adjustment below, correctly I think. the only thing to adjust was actually a star shaped screw that I was able to adjust with my smallest allen wrench.
When I turned it counter clockwise it loosened up the rear brakes (yeah!) but I unscrewed it even further and clear fluid (( assume hydraulic fluid) came out. A tiny amount, maybe 5 large drops.
I quickly screwed it bad in (fearing I'd lose all hydraulic fluid .)

No more fluid leaked out and the breaks are fine (and not too tight as they were before).
QUESTIONS:
1. Is this screw also for beeding the hydraulic line?
2. If so, does that screw do double duty as tightness adjustment *and* bleeding?
3. Or was the fluid discharge just a side effect of reducing the tightness?

Thanks!



Originally Posted by cascade168 (Post 7329469)
Is there no reach adjustment screw in the lever pivot post??? This may be your only problem. First, look into that. Usually, this is a 1.5 or 2.0mm allen screw that goes through the pivot on the brake lever.
http://www.sram.com/_media/techdocs/95-5013-109-000.pdf

and see step 7 for more exact infomation. This is the Juicy 5 .pdf



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