clutch bleeding

ok I know this is an old thread, but here is the deal.
when bleading the clutch, after you get the air out of the line, loosen the bolts on the clutch slave so that it is about 1/4" - 3/8" from the engine case.
pump up the lever to build some pressure and retighten the bolts.
good as new.
what happens is if you dont seperate the clutch slave from the engine case it will take a week of pumping to build up the pressue.
so by having a space and pumping the lever up, when you retighten the bolts it forces the fluid back into the reservoir and build pressure in the system.

just make sure you tighten all the bolts a bit at a time untill it is fullt seated

 

I did that last night at least 3 times and every time the clutch ended up with the same pressure. Dont get me wrong, I do have some pressure on the clutch lever, i just dont have enough travel on the piston to push the clutch lifter rod in enough for the clutch to fully disengage. I say this because while the bike was on the center stand and in 1st gear I pressed on the clutch lever and I could barely move the rear wheel, this tells me that the clutch it is still draggin and I dont want to ride the bike like this, I need to figure out how to get more pressure or more movement on the piston so that when the clutch lever is pressed, the clutch is fully disengaged.
thanks

 

Huge thanks!

Just reviving an old thread here, but I came across this issue while cleaning and rebuilding the VFR I just bought a couple of weeks ago and was having major hassles getting my clutch to bleed. After reading this I cracked open the top banjo and hey presto, issue resolved so thanks guys, big time!

Daz.

 

hard to tell from your description, but when are you letting go of the clutch lever? after or before you tighten the bleeder valve back down?

and after you have done the whole bottle of fluid, which is definately a lot, those skinny little lines don't hold that much, when you bleed again, are you still getting air bubbles out or no? What I am trying to get at is is there a problem with your bleeding, or are your clultch lines good, but not engaging your clutch because something is wrong there? Know what I mean?

I would really look for a leak along the whole system, take a rag or paper towel and make sure all your surfaces and connections from your resovoir to your bleed valve are stone dry. Then after bleeding pump the clutch and feeel with your bare fingers for any fluid. A small leak of clean fluid can be hard to spot. It may also be that your bleed valve, when you tighten it back up is no longer sealing. You don't notice it leaking because the hose in on there and there is already fluid on the area. So you might want to remove that hose and dry off that area as well, try listening as you release the lever and see if it is sucking in air that way.

for jchag - I have done it without putting the jar above the bleeding valve, in fact that is the only way I have done it, since I want the fluid to flow out. And I want any leakage to follow the tube down into the catch jar. I would agree about the clear tube though.

 

OK didn't even realize this was a resurected thread, mea culpa

 

Yah this is some really old stuff but it never hurts to review the basics again. I was shocked when I saw how old this one was! I think I have moved four times since this thread was originally posted and I've had three different viffers.

 

This thread is older than my time here, however I have some good experience I will add, hopefully it will help someone else.
But first - to Chris71Mach1 !! No fluid will flow if your lever is squeezed. Doing so moves the piston in the master cylinder past the feed hole from the reservoir that refills your master cylinder. That is necessary for the system to build pressure in the outward line.
It's the pumping action of this piston that pushes fluid through the system. It is possible though for some some fluid to flow with the lever all the way open, as then route from the reservoir is open to the cylinder and the rest of the system. So if you push the caliper pistons in at the bottom end, you will see fluid flow back up into the reservoir. Make sense?

Ok, here is some wisdom I posted a few yrs back on another forum:
~~~~~~~~~~~~~~~
Even with the above standard methods there are some "tricks" that you can use when you just can't seem to get there.
Think like an air bubble; meaning, looking at the brake line/fluid path, take note of anywhere that air could get trapped that is higher than a bleed point.

For instance, when I am bleeding the right side caliper, I turn the wheel all the way left, to try and get the caliper tipped so that the bleed nipple is the highest point. Putting it on the sidestand works well too, but you can't do that for the left caliper - up on a track stand or center stand with forks turned full right is best for the left caliper.
Another spot is deep in the calipers where the pistons live. Taking the calipers off and pushing in those pistons by hand may release some air up to the bleed nipple.

Another tricky spot is the output end of the master cylinder between where the banjo bolts for the brake lines are attached; because of the tilt of the handlebar, its higher and can hold air. It helps me a lot to take the brake master cylinder off the handlebar and (carefully) hold it tipped so that the end with the lines attached is LOWER than the reservoir tube. Work the lever this way and you can get the air to come back up the master cylinder and actually up into the reservoir. Note - its VERY hard to do this without spilling the brake fluid if you do this with the top of the reservoir off!

Be careful if pumping the lever with the reservoir cap off. If you let it "snap" back by letting go of it while it is squeezed, some fluid will be sucked back from the lines up into the reservoir, and sometimes splash out. However, this effect can be used to your advantage in the above paragraph.

If you do not have steel lines straight to each caliper, you may have a junction where the single line splits into two; this could be another air trap that you will need to consider.

Along with all the above, banging a screwdriver handle on the caliper/brake line/ master cylinder while doing all this will help shake the bubbles loose and get them to rise up the system.

Hope this helps. With some practice and creativity you too can have rock hard abs, er, brakes !

 

It's all been covered before, but:

Because air can hide behind the slave cylinder piston, you might try removing the entire slave cylinder from the sprocket cover and holding the piston fully retracted by means of a C-clamp while bleeding. Another method on this thread addresses this in a different way.

Another hint that sometimes helps is to loosen and remove the clutch mc from handlebar and hold it upward with lever topmost so that air can travel up to the reservoir.

And be extremly careful not to over-tighten the long bolts securing slave cuz it's not difficult to destroy the threads on the engine case. (PHOTO)

 

This thread saved me hours, I bled the clutch system as the previous owner had bought a new master cylinder but hadn't got round to fitting it, and i just couldn't seem to get pressure.

Came away and read this and got it working with the banjo technique in a few minutes! I had to keep pumping after closing the banjo and bubbles kept on coming til I had pressure.

Loving the forums guys

 

I wanted to share my experience in bleeding my clutch. I too was correctly pumping the lever, holding, then cracking the bleed valve, then tightening, then pumping again. No joy.
By happenstance, as I had the clutch reservoir open, I noticed that if I jiggled the clutch lever a little, air came out of the fluid return hole. (I think it was that one, maybe the other), so I kept squeezing it slightly then release, over again. In a fairly short time, I started getting pressure. I continued gently squeezing it and then I was up to full pressure. Works great now!

 

Loving this! sub'd