Bleeding my clutch

[Jonah]

I can,t get all the air out of the hydraulic clutch line.

Any tricks of the trade i should know?

Youtube is failing me....

[bikenut]

Try back bleeding. Push brake fluid up from the slave to the master on the handle bars. Just watch the master close so you don't over fill it . just suck some fluid out of the master if it gets to full. Good luck

[SpencerPJ]

This is the best trick out there.

Fill reservoir 3/4 full, leave cap loose, but on. Squeeze lever all the way. Tie off with rope. Let sit a few hours, or overnight. The open system will let the air naturally come out. I had troubles a few years ago after replacing the slave, and did this, works like a charm.

[Jonah]

Found the answer in previous threads....

I never would have thought to feather the clutch till the tiny bubble stopped.

[cowpuc]

Found the answer in previous threads....

I never would have thought to feather the clutch till the tiny bubble stopped.

 

 

Yep,, thats a good one for sure IMHO.. Another thing that often helps with mine has to bleed at the banjo bolt up on the master... Amazing how little air it takes to get a squish happenin.....

[Skid]

I changed out the Slave a few months ago and it took several times wiggling the handle to work out the bubbles. After a while I let the bike idle to vibrate out bubbles and also tied the clutch back over night. Took sometime but it all worked.

[Condor]

I changed out the Slave a few months ago and it took several times wiggling the handle to work out the bubbles. After a while I let the bike idle to vibrate out bubbles and also tied the clutch back over night. Took sometime but it all worked.

 

I've said this before and I guess I need to say it again. Holding the lever back against the grip over night will NOT let the air escape from the system. It's a physical impossibility... When the lever is pulled back the master plunger closes off both the expansion and the feeder holes between the base of the reserve and the piston. When the lever is at rest the plunger lip sits behind of the expansion and in front of the feeder (larger) hole, and any air in the system will rise and hopefully make it into the master cylinder, and bleed out thru the expansion hole...if it doesn't get stuck behind the banjo bolt... That's why some folks give up and come back the next morning and all is good with the world again... It's just the sitting over night that sometime helps. When the air is hung up behind the banjo the jiggling will let the air escape a tiny bit at a time, and sometimes that's good enough. All this takes time. As mentioned previously forcing the fluid into the slave and carefully filling the reserve will save a lot of time and frustration. Once the air is out of the system normal bleeding will take care of the bi-yearly job....

[Marcarl]

I agree with you Condor, I always wondered how the overnight method works with the cylinder closed off with the plunger, just didn't make any sense to me, but it seemed to work for some so I kept my mouth shut. But now I have a theory, maybe off the wall, but a theory nonetheless. When a feller would tie the handle back for an overnight procedure, it would then put constant pressure (not much maybe) on the system including the remaining air bubbles, which would then under the process gather together at the top of the system and then when the handle is released there would be 1 bubble left to get through the escape hatch, and voila! all air has been purged.

[Condor]

I agree with you Condor, I always wondered how the overnight method works with the cylinder closed off with the plunger, just didn't make any sense to me, but it seemed to work for some so I kept my mouth shut. But now I have a theory, maybe off the wall, but a theory nonetheless. When a feller would tie the handle back for an overnight procedure, it would then put constant pressure (not much maybe) on the system including the remaining air bubbles, which would then under the process gather together at the top of the system and then when the handle is released there would be 1 bubble left to get through the escape hatch, and voila! all air has been purged.

 

I'd tend to agree with you too Carl,,,,, but it would take a lot more presure to compress the bubbles than what's applied in the clutch system. In the brakes it works but that's a whole 'nuther animal... MOF a bubble is more buoyant when uncompressed... Compress a bubble enough and it will become soluble and will go nowhere.... I'm a big fan of reverse bleeding the clutch. It takes 15-20 minutes and it's a done deal....

[slowrollwv]

I put a new slave on mine just after Skid did his. What I did was put a 1/4" clear plastic hoes on the bleeder and had it open while I filled the reservoir when fluid started to fill the hose I shut the bleeder. Toped it off and pumped it a couple times to make sure I had pressure and no air and was done.

[bongobobny]

I use speed bleeders and a vacuum pump and never had any problems...

[Marcarl]

I'd tend to agree with you too Carl,,,,, but it would take a lot more presure to compress the bubbles than what's applied in the clutch system. In the brakes it works but that's a whole 'nuther animal... MOF a bubble is more buoyant when uncompressed... Compress a bubble enough and it will become soluble and will go nowhere.... I'm a big fan of reverse bleeding the clutch. It takes 15-20 minutes and it's a done deal....

 

Further on my thinking: If the air is compressed, and I agree, not much in the way of compression, the bubble(s) is smaller yet contains the same amount of buoyancy but less outer surface restriction, it would rise to the top easier? and once there combine with others of the same nature ans so create a large bubble that would want to exit quickly and efficiently? Just thinking out loud.

[Marcarl]

I use speed bleeders and a vacuum pump and never had any problems...

 

can you explain what you mean by: never had any problems? :think:You must be one of a kind!!!

[camos]

I use speed bleeders and a vacuum pump and never had any problems...

Bit of overkill there but whatever works for you is great. I use a 24" hose and an 8mm wrench and it takes 10 minutes to bleed the clutch. This is of course on a Gen 1 Mk II and all other Ventures may not be as easy.

[7 lakes]

I've said this before and I guess I need to say it again. Holding the lever back against the grip over night will NOT let the air escape from the system. It's a physical impossibility... When the lever is pulled back the master plunger closes off both the expansion and the feeder holes between the base of the reserve and the piston. When the lever is at rest the plunger lip sits behind of the expansion and in front of the feeder (larger) hole, and any air in the system will rise and hopefully make it into the master cylinder, and bleed out thru the expansion hole...if it doesn't get stuck behind the banjo bolt... That's why some folks give up and come back the next morning and all is good with the world again... It's just the sitting over night that sometime helps. When the air is hung up behind the banjo the jiggling will let the air escape a tiny bit at a time, and sometimes that's good enough. All this takes time. As mentioned previously forcing the fluid into the slave and carefully filling the reserve will save a lot of time and frustration. Once the air is out of the system normal bleeding will take care of the bi-yearly job....

 

I agree. Id never heard of this "method" before reading about it here and have racked my brain trying to figure out how this would help, eventually coming to the conclusion you did, that the real benefit was that the system was just left alone for a while. Bleeding needs to be done gently, pump pressure up in the system too enthusiasticly and air bubbles break down into millions of teeny ones, and is a lot harder to get out that way. Letting it sit and letting them all become one air bubble again can help a lot, otherwise you can pump and bleed a long time. I'm convinced that is behind a lot of the problems I read about bleeding brakes. This sounds a lot like "forced patience ", which is what is required to gently milk a master cylinder when bleeding it. Pump that thing hard and fast, or too many times, and walking away for a while is about the only way you're going to get it done.

 

In one thread I read where a guy said he had to do this regularly and I just bit my tongue.

[videoarizona]

Bit of overkill there but whatever works for you is great. I use a 24" hose and an 8mm wrench and it takes 10 minutes to bleed the clutch. This is of course on a Gen 1 Mk II and all other Ventures may not be as easy.

 

 

Agreed. The longer hose works for me as well. Routing it up in a big loop allows me to keep the bleeder open and watch the air bubbles. Slow and easy... and if the system is in good shape, it should only take 15 minutes or so.

[camos]

Agreed. The longer hose works for me as well. Routing it up in a big loop allows me to keep the bleeder open and watch the air bubbles. Slow and easy... and if the system is in good shape, it should only take 15 minutes or so.

The loop does not need to be very large, just enough so that there is always brake fluid at the bleeder otherwise air can get in. Since this method is moving fluid at 0 pressure there is not much force to break up air bubbles. I usually pump fast just because it is the movement of the fluid that carries the bubbles downward so so pumping slow will allow the bubbles to rise which can only delay the process.

 

This method works very well for me every time without fail.

 

I can still remember with clarity, about 10 years ago spending 7 hours, on again off again while working a night shift, trying to get the front brakes on my Virago bled. I bet I tried every failing suggestion that shows up in posts like this. Tying the brake lever half way in was my Hail Mary attempt that did finally get enough brake pressure to make the trip home. So while that method does have some validity, it does not come close to being a good solution.