New front brake and clutch reseviors ~ help bleeding

[dennisd]

I did a search but couldn't find the answer I need.  I just replaced the front brake and the clutch reservoirs on my M1100 with Risoma parts.  Couldn't stand those plastic OEM pieces.  Anyway, I haven't got the systems bled yet.  To change the reservoirs all I did was dump the fluid out of the OEM ones, then pull the OEM pieces from the supply tubes going to the master cylinders and insert the new reservoirs.  I then filled the new ones but even by tapping on the tubes I couldn't get a lot of air out so I need to bleed.  Since no air should have gotten past the master cylinders I was wondering if the fitting on top of the master cylinder is a bleed fitting?  If so, it would be much quicker to bleed them first then double check by bleeding at the slave cylinders.

[ducpainter]

If the supply tubes were never emptied there may not be air in the system if you haven't already fully pulled the levers.

Try just tapping on the brake and clutch levers and see if any air pops out of the tubes.

What fitting are you referring to on the masters?

[dennisd]

Those look like bleeder fittings to me near where the master cylinders clamp to the handle bars.  Am I wrong?  If these are bleeders, it will be fairly simple to remove any air that got in through the supply hoses.

[Howie]

Yes those are bleeders.  As ducpainter said, if you just dumped the reservoirs you do not need to bleed the brakes.

[dennisd]

Thanks for the responses.

When I first went into the project, I didn't think I'd have to bleed the systems either.  However, when I dumped the OEM reservoirs I think it formed some siphoning action and at least partially drained the supply hoses.  I say that because when I pulled the OEM reservoirs from the hoses there was no fluid in the hose that I could see.  That's why I will use the bleeder in the pics to remove the air from the supply hoses.  This was a smart set up putting a bleeder on the master; makes things much easier than having to bleed the entire system.

[dennisd]

OK, followup.  Glad I did bleed the systems (I used the bleed screw on the master cylinders).

Got quite a lot of air bubbles for quite a few cycles of bleeding.  I'm sure glad the master cylinders had bleed screws on them so I didn't have to force the bubbles through the entire systems.  I think it would have taken a lot longer.

[howiroll]

I am going to do this same setup and have never bleed a system before.  How exactly did you use the bleeder fittings at the top of the clamp (I assume you are talking about the nipple thing at the top)?  Basically, looking to see step by step how you accomplished this.  It would be a huge help because I am a moron when it comes to bike fluid dynamics  .

[Slide Panda]

There's a tutorial on bleeding the rear caliper here:
http://ducatimonsterforum.org/index.php?topic=16142.0

Not exactly what you need - but covers the basics.

Basically, bleeder fittings are bleeder fittings regardless of position. The fittings basic operation doesn't change, in theory. In the real world, if you're trying to get air out of a column of fluid, it makes sense to have ones at the top... but I'm off topic.

What you need to do is install the new reservoirs and add fluid. I'd let it sit for a bit, and a bit of a tap or shake to help any clinging bubbles work their way up to the reservoir. After that you start at step 9 in the link I gave.

Be sure to use clear hose, so you can see bubbles. If you have a mushy lever (and none of the ladies like a mushy lever) after that, then you might have to do it the hard way and bleed through from the caliper.

[avizpls]

I usually flip the bike upside down so the calipers are the top of the system. All the air goes right to the bleeder

[howiroll]

God I wish I had Jedi powers to do that.

[howiroll]

dennisd sent me a great email describing the best way to do this and thanks for taking the time dennisd.

"First and foremost; place some rags and then preferably cover them by plastic of some sort on any painted surfaces before even thinking about removing the covers from the stock reservoirs and have plenty of extra rags around just in case.  This needs to stay in place till the job is complete.  If you don't already know this; brake fluid will damage and even remove paint in the blink of an eye.

Use some pliers to move the hose clamp on the reservoir end of the hose back so the hose is loose on the nipple.  Don't loosen the clamp at the master cylinder end.   Remove the cover and simply twist the reservoir and pour the brake fluid out.  Now you can SLOWLY pull the reservoir from the hose being careful not to sling brake fluid around.  Wrapping a rag around the reservoir might help keep things neat.  Ok, now I'll wait while you wipe up all that spilled brake fluid.

Figure out where you are going to mount the new reservoir and measure and cut the stock brake hose to fit.  You might want to cut it a little long and have more bend to it just to make sure it will fit when completely installed.  You can always cut shorter but not add back on without replacing the hose.  Mount the reservoir all up and attach the hose, making the final adjustment to the hose length if necessary.  You cut it too short didn't you?  Ok, go buy some new hose; I'll wait, AGAIN (sorry, just a little ribbing).

Fill the reservoir with new fluid and set the cap in place loosely.  Use some hose that fits the bleed nipple and run the hose up from there about 6 inches then back down into a catch container.  You might want to secure the end in the container to make sure it doesn't come out and spill even MORE brake fluid.  I also usually put a small zip tie (wire tie) around the hose where it fits on the bleed nipple to help hold it on.  By arching the hose up, fluid will be kept against the bleed fitting, not allowing air to possibly get back in through the fitting.  BTW, clear hose works best so you can monitor the air bubbles coming out and know when there is no more.  Pump the lever a couple of times then squeeze and hold the lever while slightly opening the bleed fitting on the master cylinder.  DO NOT RELEASE THE LEVER TILL YOU TIGHTEN THE BLEED FITTING AGAIN.  When you open the fitting, the lever will go all the way against the grip and fluid will be forced out the fitting.  If you release the lever before tightening the bleed fitting, air might get drawn back into the system.  Keep repeating this till you no longer see air bubbles coming out the bleed fitting (you did use clear hose, right?).  Important note:  monitor the fluid level in the reservoir closely and refill as needed so you don't draw it down too much and suck more air in through that end.  Also, release the lever slowly after tightening the bleed fitting because releasing it too fast can cause a flash of fluid in the reservoir which might splash out.  That's why I suggest setting the cap on loosely to help prevent splashes.

Since you didn't introduce any air into the system further down line than the hose feeding the master cylinder, you should be able to get all the air out through the fitting on the master cylinder.  OK, you got all the air out.  Congratulations!!  Now clean up the outside of the reservoir and cap then clean it again.  Remember, brake fluid does nasty things to shiny surfaces.  I was able to get all the air out without touching the bleed fittings on the slave cylinders.  You will just have to see if it works for you.  You will know you got air in the system if the lever feels mushy.

All you have to do is repeat this for the other reservoir.

Done?  Great, grab a lawn chair, sit back with a cool one and admire your work.  drink"

For everyone's enjoyment.