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Living the Dream
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Long story short, I took the bike off the stands in April, she started right up, but when I went to put it into gear the lever came straight back with no pressure, and won't go into gear. I rolled it into the garage, attempted to bleed the clutch as I have done before with no luck. I have swapped out the reservoirs in case it was an issue with the black diaphragm thingy in the reservoir, with no luck, and after reading threads on here, I am at a dead end. :banghead:
One thing I do notice, is that I am not getting any bubbles when I am pressing the lever with fluid in the reservoir, so it makes me wonder if the master cylinder has gone bad, or if something else is wrong here.

I would really like to ride my damn bike, as it has been since October, and could really use some help. Thanks in advance.

Chris
 

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when you bleed it, do you get any feel at all? you might have a big air pocket, and the clutch side isn't the easiest to bleed. Its a pretty simple system though, it could only be a couple of things. Either the seal in the master or slave is dead, or there is an airbubble trapped in there.
 

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Living the Dream
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I don't get any feel at all. I even have a lot of suction on the bleed valve when I am trying to bleed it, so I would think any air pocket would be sucked out. I feel like I am taking crazy pills here.
 

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are you using a mightyvac or something on the bleeder side? have you tried just bleeding slowly the traditional way?
 

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?

Chris;
remove the slave.....is it leaking?

you get 2 choices;
the M/C seal or the slave seal

with the slave removed and it not leaking put a small C clamp on the slave piston.....pump the M/C
pressure? or no.....its the M/C
 

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When I replaced the slave on my Brutale it took what seemed like hours to get any pressure back in the lever. There was a particular point at pulling the lever towards the handlebars when bubbles would appear, moving the lever a couple of mm back and forward at that point eventually got there for me and then a normal bleed procedure sorted it all out from there.
 

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Living the Dream
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Discussion Starter #9
as for bleeding, I am using a large syringe to provide sucking pressure, getting small bubbles out of the bleed valve, but not a constant flow of fluid.

I will try a few of the things mentioned here before I go and buy a new M/C. If I go that route, I swear I had seen some decent options less than $200, but can't see to find them again.

I appreciate all your help gentlemen!
 

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sometimes the angle at which the master cylinder sits does not allow the air to get out of the system if you are just pumping the handle. Take your syringe and put it in the reservoir right on the hole where the fluid enters the master cylinder. Keeping a tight seal extract any air that might be caught int the master cylinder. I had the same problem until I did this.

That still doesn't explain why it failed just sitting in the garage
 

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+10

sometimes the angle at which the master cylinder sits does not allow the air to get out of the system if you are just pumping the handle. Take your syringe and put it in the reservoir right on the hole where the fluid enters the master cylinder. Keeping a tight seal extract any air that might be caught int the master cylinder. I had the same problem until I did this.

That still doesn't explain why it failed just sitting in the garage
George has a point Chris, those Nissan M/C's can be a bitch once they've had air in them. Remove the M/C from the bar so you can twist it to make sure the air goes UP.
Be patient, and bleed it the conventional gravity way.
 

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You might even have to crack the banjo bolt to get the last of the air out. Don't buy a new master cylinder, you will shit your pants when you get the price. Just get a rebuild kit for a nissin cylinder with a half inch bore they are on tons of different bikes so should be easy to get and you might even find simply stripping the M/C and cleaning and reassembling will rectify the problem, did for me.
Good Luck. Cus
 

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Just a random thought...Are you sure you haven't lost the little pin that sits in the clutch lever/ little metal barrel and pushes on the piston ?....That would achieve the result you are enjoying Chris ..

joe
 

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G.day went for a ride only to find my clutch started to drag, so much so when i arrived at my destination i found the clutch had failed totally with no fluid in the reservoir at all, with no obvious drips on the bike or fairing i can only imagine the fluid had drained into the clutch housing so contaminating the oil, i managed to ride home with no clutch at all changing gear by gently pulling throught the gear then backing off whilst dropping down a gear, when i removed the chain cover i found there was evidence of hydraulic fluid along the clutch push rod, so cleaned the rod and housing smeared with rubber grease and refitted. Once i refilled the reservoir and bleed the line my clutch has been fine so far , but will have to keep an eye on the fluid if the problem recurs remove the clutch seals and replace.
 

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G.day went for a ride only to find my clutch started to drag, so much so when i arrived at my destination i found the clutch had failed totally with no fluid in the reservoir at all, with no obvious drips on the bike or fairing i can only imagine the fluid had drained into the clutch housing so contaminating the oil, i managed to ride home with no clutch at all changing gear by gently pulling throught the gear then backing off whilst dropping down a gear, when i removed the chain cover i found there was evidence of hydraulic fluid along the clutch push rod, so cleaned the rod and housing smeared with rubber grease and refitted. Once i refilled the reservoir and bleed the line my clutch has been fine so far , but will have to keep an eye on the fluid if the problem recurs remove the clutch seals and replace.
It's the slave cylinder seals mate.
 

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I might have the same issue. Suddenly my clutch pressure was gone when I opened the reservoir it was empty. I filled it up again and had the pressure back for about 15 miles the fluid just disappears.

Where does the fluid go? Do I need a new clutch slave cylinder?

Thank you.
 

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I might have the same issue. Suddenly my clutch pressure was gone when I opened the reservoir it was empty. I filled it up again and had the pressure back for about 15 miles the fluid just disappears.

Where does the fluid go? Do I need a new clutch slave cylinder?

Thank you.
Judging by those pictures, I'd say you know where the fluid is going, yes the seal is done and a new slave cylinder seems to be the way to go.
 
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