Avid juicy 7's
Author
Discussion

lingus75

Original Poster:

1,705 posts

251 months

Tuesday 7th October 2014
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I have finally got back on the bike after a long period of laziness. My Old Orange has been serviced and working well. However, my Felt with the disc brakes has suffered somewhat with no use.

Replaced chain, a good clean up, new gear cables has been done. The brakes aren't so good. Lever travel is very long and I can't adjust on the lever anymore. I am inexperienced with hydraulics, so was wondering if this problem is resolved with merely a top up of fluid?

I noticed that every now and then a bit of fluid would come out of a small hole in the reservoir, I guess this is normal?

Or perhaps the system need new seals etc...?

barker22

1,037 posts

196 months

Tuesday 7th October 2014
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Fluid anywhere other than inside the system is not a good sign. I would first start by replacing the fluid and bleeding the system, you should get good resistance if it is done correctly.

gazza285

11,137 posts

237 months

Tuesday 7th October 2014
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lingus75 said:
Avid
There's your problem, horrible things.

Gren

2,030 posts

281 months

Tuesday 7th October 2014
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Nothing wrong with their more recent offerings but the Juicys never had a good reputation especially when it came to bleeding.

skoff

1,387 posts

263 months

Tuesday 7th October 2014
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I've just got rid of some Avid Juicy somethings... not 7, possibly 5... anyway, I found them a real PITA to adjust / bleed. Swapped them out for Shimano XT, which are much nicer and really easy to work on. Not too expensive either

P-Jay

11,404 posts

220 months

Tuesday 7th October 2014
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Current gen Shimano hydraulic brakes of any type are worlds better than Juicy 7's which were frankly a bit st 8 years ago.

Avid will sell you any bits like replacement seals or pistons you like, but they're horribly expensive for what they are - get some Deores for £40 an end instead, they come with new pads which are £15 an end alone!

Watchman

6,391 posts

274 months

Tuesday 7th October 2014
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No hydraulic fluid shouldn't "leak" at all. If it does, you need to find the cause of the leak first.

Then you cannot simply "top up" the fluid. The system will need bleeding. You can do this with "kit" you can buy for about a tenner which includes a syringe, some hoses, a small pot of fluid and blah blah blah, or you can do what you have to do with old Shimanos which is:

1. Remove wheel
2. Remove brake pads
3. Remove reservoir cap and baffle
4. Put 7mm ring spanner onto calliper nipple
5. Put length of hose over nipple, into waste bottle
6. Pour hydraulic fluid into reservoir, filling it but taking care not to spill any, or have abundance of rags available
7. gently squeeze lever
8. Briefly open nipple, closing it before lever has reached full travel
9. Repeat 7 and 8
10. Check level of reservoir, topping up if necessary
11. Repeat 7 and 8 over and over, until the fluid ejected contains no more bubbles. Continually check reservoir level and top up as necessary.
12. Clean everything and reassemble.

Easier with another pair of hands - and some coordination between you. I can do it on my own but it has taken some practice.


In practice this can work as well as the syringe method but the syringes offer some benefits for people (like me) who like to do things the proper way. You get to expose air in the fluid (by creating a vacuum around the fluid) and rid yourself of the bubbles easier with syringes. Also, with syringes you pump fluid upwards (the way bubbles prefer to move) from the calliper to the reservoir, and it's far less messy. Thing is, the cheap syringe kits are rubbish whereas the good ones are ~£30.

Lastly, the little kits come with 100ml of fluid. Good for bleeding an already working system but for a new "fill" can sometimes be not quite enough. I buy a litre at a time. It lasts me ages and I'm not pressured into making it work with an inadequate supply.

jshell

12,056 posts

234 months

Tuesday 7th October 2014
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gazza285 said:
lingus75 said:
Avid
There's your problem, horrible things.
I'm afraid so. I'm in the middle of changing out all my SRAM/Avid gear with Shimano. 2 winters killed the SRAM groupset and Avid brakes.

Justin S

3,658 posts

290 months

Tuesday 7th October 2014
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Avids do show damp round the hole in the lid, its just the diaphragm being able to move. Its nothing to worry about. You can bleed Avids to get them to work again, but they are a bit more tricky than most. See you tube for help. Avids can work well. I have just taken a set of 7's off a bike I ride to work every day for the last 6 years with ony one set of rear pistons and seals (£7) and off we went again. Although, if you repiston and bleed with the correct kit, you are halfway to a set of deore brakes, which the latest offering are just immense.

lingus75

Original Poster:

1,705 posts

251 months

Wednesday 8th October 2014
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Justin S said:
Avids do show damp round the hole in the lid, its just the diaphragm being able to move. Its nothing to worry about. You can bleed Avids to get them to work again, but they are a bit more tricky than most. See you tube for help. Avids can work well. I have just taken a set of 7's off a bike I ride to work every day for the last 6 years with ony one set of rear pistons and seals (£7) and off we went again. Although, if you repiston and bleed with the correct kit, you are halfway to a set of deore brakes, which the latest offering are just immense.
Thanks for the replies.

I have found them good, but coming from a background of canti's and rigid steel frames any disc brake setup would impress me!

I'm not looking to replace yet, so I will try a bleed. There is a tiny little hole in both reservoirs which is where a tiny amount of fluid sometimes comes out when lever is squeezed. This must be a design/flaw of the system?

I think I will need to learn about disc brakes! Stripping/building the old Orange is easy. Some investment in new tools is required.

Watchman

6,391 posts

274 months

Wednesday 8th October 2014
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lingus75 said:
There is a tiny little hole in both reservoirs which is where a tiny amount of fluid sometimes comes out when lever is squeezed. This must be a design/flaw of the system?
Can you post a pic of it? Hydraulics really shouldn't weep at all.

lingus75

Original Poster:

1,705 posts

251 months

Wednesday 8th October 2014
quotequote all
Watchman said:
an you post a pic of it? Hydraulics really shouldn't weep at all.
I should have read the last response! It's the diaphragm moving so appears normal. Not at home but will have a proper look later and hopefully get it sorted!