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Bleeding 999S fronts brakes?

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I can't get my front brakes to really firm up after changing fluid (Brembo radials). I screwed up and let my master suck a little air but have run a lot of fluid through the system now. It's starting to piss me off! :)

I got to thinking there might be some air hanging in the master cylinder or something. Should I try cracking the banjo bolt? Does it take more than a bottle of fluid to purge this system?

Any opinions or tried and true methods out there?

Thanks in advance.
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unbolt the master cylinder so you have an always upgoing path for the airbubbles.

Use a LARGE plasticsyringe filled with brakefluid and push the fluid from the bottom (caliper bleeder bolt) towards the top (master cylinder reservoir).

I garantee that it works.

A plastic syringe (LARGE) can be bought at a drugstore.

I use the technique since you´ve got the air working FOR you instead of against you. It WANTS to rise, so why try and force it downwards? I did my clutch and front brakes with 1/4 bottle of fluid and in about 10 minutes, without any help.

The really tricky part is unbolting the master cylinder and hanging it so the "flow" only goes up.

//amullo
 

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amullo said:
unbolt the master cylinder so you have an always upgoing path for the airbubbles.

Use a LARGE plasticsyringe filled with brakefluid and push the fluid from the bottom (caliper bleeder bolt) towards the top (master cylinder reservoir).

I garantee that it works.

A plastic syringe (LARGE) can be bought at a drugstore.

I use the technique since you´ve got the air working FOR you instead of against you. It WANTS to rise, so why try and force it downwards? I did my clutch and front brakes with 1/4 bottle of fluid and in about 10 minutes, without any help.

The really tricky part is unbolting the master cylinder and hanging it so the "flow" only goes up.

//amullo
You guys are awesome!
 

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Bobaganoosh
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amullo said:
Use a LARGE plasticsyringe filled with brakefluid and push the fluid from the bottom (caliper bleeder bolt) towards the top (master cylinder reservoir).

A plastic syringe (LARGE) can be bought at a drugstore.
//amullo
I dont think any state allows you to buy syringes over the counter at drug store any more...US kinda has this drug problem and damn druggies like syringes!

If you dont have the access to a syringe, get a MityVac, best 40 bucks I ever spent!

http://www.mityvac.com/
 

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+1 on the MityVac, I've been using one for years now to do the bulk of the bleeding and the final bit by hand. Also comes in hand for other task such as removing extra fluids.
 

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The syringe i use is NOT for injecting yourself. It´s a LARGE plastic syringe that is used for water-flushing noses and ears. You couldn´t stick yourself with it if you tried, since there isn´t a needle or even the possibilty to put one on there.

In any case, the theory still stands. Force the bubbles UPP, not down. But make sure you empty the reservoir first, since your pushing the fluid into it.

EDIT: This is the one i use. Cost me about 15$
http://www.camexco-inc.com/01_about_nasaline/01_01_about_nasaline.html


//amullo
 

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plus one on the speed bleeders. i used them on my aprilia. i haven't seen much talk about them on here though.

i think it was around ten dollars or so a bleeder. money well spent. one way bleeder valve on the calipers. doesn't get any easier than that. pump the brakes and keep pouring brake bluid till it runs clear.

works on the clutch too.
 

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Since Were On The Subject. I Bought Some Roll-a-clicks The Other Day, I Ran Hope To Through Themon And In The Process Of Either Removeing The Push Rod Or Tring To Re Install It I Ripped The Dust Boot That The Push Rod Slipps Into. Well There Was No Leeking But I'm Still Uneasy Of Not Having It There. I Keep My Bike Very Clean And So On And So Forth. Last Minute I Called My Parts Man And He Says I Need A Rebuild Kit For The Cylinder And Push Rod Assemblie. Do I Really Care. Not Really. Do I Want It To Be Correct, Ya. Is It Going To Leave Me Stranded Or Worse, A Weak Clutch In Time Of Need, Who Knows. All I Do Know Is The Brake Side Went Smoothly, I.e. Live And Learn. They Look And Feel Great, They Need Miner Adjustmant But All In All Pretty Smooth.

I'm Glad To Read This Thread Because Soon I'm Going To Replace My Clutch Slave Cyclnder And Will Be Needing Help On Steps On How To Bleed And So On.. I Understand The Fundamentals Of The Process But Just Never Done It.
 

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Discussion Starter · #10 · (Edited)
Synergy said:
I dont think any state allows you to buy syringes over the counter at drug store any more...US kinda has this drug problem and damn druggies like syringes!

If you dont have the access to a syringe, get a MityVac, best 40 bucks I ever spent!

http://www.mityvac.com/
I have a Mityvac...The Mityvac is pullling air past the threads on the caliper nipple.

I got a couple of big syringes and 3 feet of the perfect sized tubing from a farm and ranch supply store for $3.43 including tax... (You can buy syringes for your horse or cow in Idaho)

Pushing the fluid from the bottom works like a charm... The bubbles that were causing the problem must have been hanging right up near or in the master cylinder. Even though I had used the usual "top down" method and put a lot of fluid through it, I had only pushed a few cc's of fluid into the caliper when a couple of bubbles came up into the reservoir...

Thanks!
 

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sblea said:
Does the "Bottom-Up" approach work with the front brakes where there are 2 lines instead of the single one?
Yepp, But you need to to both sides ofcourse. And you may need to repeat it after a night of it just sitting, but since one side is static the chances of pushing air into that side of the brakes is small.

I use the procedure for all my brakes and for the clutch.

//amullo
 

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trussdude said:
On the new 749/999 bikes, there is a small bleeder located inside the master cylinder resovoir. It's best to use a 6 mm nut driver. The stock master cylinders tend to suck a lot of air.
I just wanted to say that this saved my ass today. I did the same thing and sucked air in my master cylinder as I was bleeding. I loosened that little 6mm thingy, squeezed the lever and a bunch of air came out. Now the brakes are firm and bite hard. Thanks Truss!

Now that rear brake on the other hand... :mad:
 
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