hhk25

I have a mountain bike with Avid Juicy 5 hydraulic brakes. The front brake has completely failed with the lever going right to the handlebar.

I tried to bleed it today using a Jagwire Elite kit for DOT fluid. I followed the instructions in the SRAM Youtube video but when I try to push the fluid up from the caliper syringe to the lever syringe, it barely moves. I have to put enormous pressure on the syringe to push the fluid through. This just didn’t seem right but there were no bubbles in the fluid so I capped the ports, reinstalled the pads and wheel and tried it. No bueno. The lever moves to the bar with hardly any resistance.

So I tried it again and had the same result.

What would be the best approach now? Could it be possible that the hose is somehow blocked? There are no leaks or kinks in the hose.

One thing I noticed is the fluid that did get pushed out into the lever syringe was quite dirty with some small black bits in it. Not a lot but noticeable.

Thanks for any advice.

Polaris OBark

I understand that this isn't the advice you want to hear, but the best thing I ever did was replace Avid Juicys on two bikes with Shimano XT.

Unless you don't have the ports fully open at both ends, what you are describing is a clogged brake line. The caliper end is most likely the culprit, if it isn't a clog. What you don't want happening is having the syringe hose pop off, spraying everything with DOT fluid. At least if Shimano mineral oil sprays in your face, it isn't an immediate threat to your skin or eyes. (Always wear safety glasses for this kind of thing.)

cpach

Juicy 5s are pretty much ancient and the amount of time and money to service both the master cylinder and the pistons, both of which likely need it at this point, would be better spent towards basically any new brake--the usual suspects being entry level Shimano brakes for less than $50 a pop.

I basically refuse to bleed these if they're not already in more or less functional condition (ie, if they just feel slightly spongey), and warn customers if they don't work well after a bleed they're still responsible for paying for our labor.

hhk25

Exactly why I quit pushing that syringe at some point. I could feel that thing was going to blow!

hhk25

Thanks the the reply. I have bled a lot of Shimano brakes but not many SRAMs. Should there be much difference in the amount of effort needed to push fluid through either system?

'02 nrs 

Try disassembling the master for the issue.theres more there that can go south than in the caliper.when apart use compressed air to clear all orfices.

andrewclaus

Bleeding doesn't always fix every brake problem. Seals fail, pistons break, lines get blocked.

I agree, it sounds like it's time for a new brake. I would enjoy tinkering with it if I had the time and could do it safely, but at that point I'd assume it's broken and just use it as a learning/forensic opportunity.

cpach

No, there is a blockage somewhere. If you want to service these to work well against my advise you will probably have to at the minimum rebuild the levers in addition to bleeding, and should also probably rebuild the calipers as well. Save yourself time and money and buy some entry level Shimano or Tektro brakes .

cxwrench

I'm of course going to recommend buy new brakes. Those old Juicy brakes suck so badly that a training rep from SRAM apologized profusely to my class at Trek Expert mechanic class. He said, word for word: We know they suck. We're trying to make better brakes. Bear with us.

well biked 

Replace the brakes, preferably with mineral oil hydraulic brakes IMO (i.e., Shimano, Tektro). Avid hydraulics were/are terrible. There are no hydraulic brakes marketed under the Avid brand anymore because of their well-earned, terrible reputation, only mechanicals.

well biked 

Our SRAM rep used to start each visit in our shop apologizing for the hydraulic brake problems.

hhk25

I guess I’ve done well to have them last this long. New Shimano brakes are on the way.

TiHabanero

You have seen the light. Shimano brakes are superior in every respect.

byscott

Good call.