2nd Gen clutch hydraulic question

1986 VFR700F

My bike was unloved by its previous owner for several years and was stored semi-disassembled. I have since re-assembled it, and brought it back to really nice running condition. I am having an interesting problem that I could use some help with though.

The hydraulic clutch will build pressure over time to the point that it causes the clutch to slip. I have bled the unit, changed out the fluid, verified that everything appears ok, but none of that helps? If I let the bike sit for a day or 2, when I go out to ride it, the clutch will engage late on the lever and it will slip. If I just crack the bleeder to let the pressure out of the slave cylinder (no lever movement) then all is well and the clutch works normally. The system is acting like there is either a stuck valve or blocked vent somewhere?

Any idea's? I am open to suggestions.

I have had the mechanical side of the clutch apart (basket and discs). I replaced the discs for good measure with brand new ones, but the problem was not solved, definitely the problem is hydraulic.

 

You're right on track with the blocked vent. Mine had the same problem after sitting for years before my own daring rescue. Now, I'm not saying that your solution will be as simple. But here's what worked for me.

If you look in the bottom of the master, there should be a much smaller hole to the left of and in line with the larger port in the bottom (not much bigger than a needle point.) From sitting for years, I'd bet that it's clogged. Take care clearing it, and know that you don't need to worry about re-installing that press-in splash guard.

If you've already got this far on your own and addressed this, I'm sorry for the insult to your intelligence. Best of luck!!!

 

Not insulted! I didn't know where to look for the vent... I will check this tonight, THANK YOU!

 

No problem, I hope it helps. Be sure to post up the results; I'm invested now!