Clutch Lever Suddenly Stopped Engaging Clutch

2007 VFR 800. I was moving my bike in the garage this morning, and the clutch felt fine. A moment later I grabbed the lever, and there was no pressure. The lever pulled back way too easily. At first I thought I snapped a cable. I put it on the center stand and confirmed that the clutch wasn't engaging at all. I searched the forums and found a few possible solutions - mainly bleeding the line. This is my first hydraulic clutch, and I don't even know what fluid goes in the cylinder let alone how to bleed it, etc. I've only had the bike for a few months, so I'm new to this model. I was just really surprised that it went from working to not working at all that quickly.

Any suggestions appreciated. I'd like to enjoy what riding I can before winter comes to northern Ohio.

 

a little air is all it needs. I'd turn the the bars full right and look in the sight glass, what do you see?

 

Looks like low fluid because none is visible in the window. So I can see that it takes DOT4 brake fluid because I only look stupid plus it's written on the cylinder cover. Guess I'll have to add and bleed and see if that solves it.

 

Yep, you got it.

 

Read the service manual and watch some youtube videos first if you have never bled before.

BE VERY CAREFUL AND VERY SLOW WHEN YOU MASH IN CLUTCH WITH TOP OF MASTER CYLINDER COVER OFF OR YOU WILL HAVE A GEYSER OF BRAKE FLUID ALL OVER YOUR BIKE! Make sure you cover up bike and wrap some old rags around the cylinder as precaution.

 

Update: The fluid in the master cylinder was milky. I noticed brown gunk coating the bottom of the cylinder. I wiped it clean and made sure the hole was clear. I managed to manually bleed the line and got clear fluid after a while. The only issue was I continually got air bubbles coming through the hose. After a while I finally put it all back together to work on it later. The master cylinder is full of clear fluid, and the lever has pressure again. A quick test of the clutch showed it working normally again, but I still need to figure out how the air is getting into the system before it will be fixed.

 

Is the problem of air getting into the clutch system common? I'm just looking for the best starting point on troubleshooting.

 

It's always good to bleed the brake or clutch mc at the banjo bolt b4 going to the bleeder screws.

 

If the fluid in the master cylinder was low, that's where your air most likely came from. Its not uncommon in hydraulic systems to have some bleed-by past even good seals. Since there isn't a large volume of fluid even in a full system, over time that little bit of bleed can add up. That's the reason for the sights on the reservoirs. When it gets that low all it takes is leaning the bike a few degrees one way or the other and if that little puddle of fluid that's left moves off of the inlet when you squeeze that handle, you've just pumped air into your line. fluids are not compressible, while air is. Since the plunger is so small a tiny air bubble can compress and consume all the hydraulic force your are trying to transmit to the slave cylinder.

 

I use a vacuum pump to pull the fluid down from the MC above. I have found the vacuum pumps are the easiest way to purge and fill hydraulic systems. I got mine at Harbor Freight for like $10 or something like that. It works perfectly and you have no mess to deal with since all the fluid is captured in a bottle.

 

it's funny that I stumbled across this post today because I just dropped my bike while trying to close my gate (bummer, got a little rash on the left side) but the interesting part is that I lost my clutch (wtf?). good thing I was still home so I opened up the MC and sure enough there is chocolate milk in there and the fluid is really low. I guess I should say that I just picked the bike up and probably should have gone through the fluid before now but I was dealing with carburation issues and didn't get around to it. Anyway, as stated above once the bike was on its side when I picked it up I must have pulled the clutch in and sucked air into the line. This gave me the excuse to dig out the vacuum pump and purged the nasty stuff and now with fresh fluid it works great again.

here is the old fluid (keep in mind it was much worse, this still has some fresh fluid mixed in). The bottle should be clear and notice the chunks that came out of the slave cylinder in the clear line...