MV Agusta Forum banner
41 - 60 of 62 Posts

·
Super Moderator
Joined
·
25,536 Posts
I have a bleeder and DOT 4, so I will try a bleed Monday morning when it is cool in the garage. Any pitfalls in bleeding the clutch? Or similar to brakes?

Grazie
Same as the brakes. You might have to finagle that pressure switch to get any air bubble out of it.
 

·
Registered
Joined
·
906 Posts
Discussion Starter · #42 ·
Same as the brakes. You might have to finagle that pressure switch to get any air bubble out of it.
Silent of Service,

"Finagle" surely must be a latin based, Italian motorcycle only terminology. Perhaps related to jiggle, or jangle or give a slight whack? I will review bleeding today, and try it early tomorrow morning before heat drives me out of garage.
 
  • Haha
Reactions: silentservice703

·
Super Moderator
Joined
·
25,536 Posts
  • Like
Reactions: Antony Ciano

·
Registered
Joined
·
906 Posts
Discussion Starter · #44 ·
All,

So I got my wife to help me with an attempted clutch fluid bleed. We followed instructions shown on this video exactly, and used the little 8 MM quick bleed wrench tool. We got fluid out and there were air bubbles. But we could NOT get a continuous stream of just clean fluid through the system. I closed the clutch valve, put on the cap and found the clutch is "mushy", less effort to pull in than normal? Then the heat drove us inside. Done for today.


What are we doing wrong? Any advice? I am afraid to start the bike and test N to first: if there is not enough clutch fluid will I damage something? Or clutch just not engage?

I also have a vacuum pump type bleeder, and need to find a small 8 mm end wrench: try it again with the vacuum bleeder? If so, while vacuuming, should the clutch handle be pulled in, or left out? Will a vacuum bleeder work better than pumping the clutch handle?

Any help very much appreciated. If I can't figure this out, and the clutch won't work, I guess I will have the bike towed to my mechanic and have him work it.

thanks
 

·
Super Moderator
Joined
·
25,536 Posts
Bleeding systems is an art form of sorts
You have to be patient and ensure you only release the bleed valve under pressure.
If you release the lever with the bleed valve open, you will draw air in.
If you allow the reservoir to go empty, you will draw air in.
My vote is to attempt again with the vacuum bleeder.
 

·
Registered
Joined
·
906 Posts
Discussion Starter · #46 ·
Bleeding systems is an art form of sorts
You have to be patient and ensure you only release the bleed valve under pressure.
If you release the lever with the bleed valve open, you will draw air in.
If you allow the reservoir to go empty, you will draw air in.
My vote is to attempt again with the vacuum bleeder.
May I ask, please: could you describe exactly how to do this with the vacuum bleeder? I can't find any videos except for older cars.

We probably have a line full of air right now, hence the mushy clutch feel? That is from releasing the lever with bleed valve open, very likely as we at first tried pumping the clutch. We did get out a tank full of old dirty fluid.

Then we tried pressure clutch in with valve closed, open valve-- hope for fluid and bubbles-- close valve, release clutch and repeat. We did that several times and at the end no fluid was moving at all out the tube.

I do appreciate anyone helping with this issue. If I can't figure it out, I don't see many options other than an expensive tow to mechanic. So frustrated. The heat here makes it horrid to work in the garage.

thanks
 

·
Super Moderator
Joined
·
25,536 Posts
Work naked like the wife and I do!

The process works best with two, but I’ve done it by myself.
My bleeder is air driven. What is yours?
 

·
Registered
Joined
·
906 Posts
Discussion Starter · #48 ·
Work naked like the wife and I do!

The process works best with two, but I’ve done it by myself.
My bleeder is air driven. What is yours?
Bleeder is hand pump type, MityVac. It has a gauge. I thought I would try the simple method first, but obviously I have no idea what I am doing.

I bought the MityVac to try and bleed rear brake myself, but impossible because I could not budge the bolt on rear brake.

Any help appreciated.
 

·
Super Moderator
Joined
·
25,536 Posts
I can certainly walk you through it.
Perhaps a FaceTime call is in order when we are both ready. Right now I’m in the pool as intended.
I can write something up a bit later.
 

·
Registered
Joined
·
906 Posts
Discussion Starter · #50 ·
I can certainly walk you through it.
Perhaps a FaceTime call is in order when we are both ready. Right now I’m in the pool as intended.
I can write something up a bit later.
SS,

This picture shows my tool set up. A write up would be wonderful please.

I would like to try again tomorrow morning, with my wife's help.

Not sure exactly the right sequence I guess.

Any help would make me most grateful.
 

Attachments

·
Super Moderator
Joined
·
25,536 Posts
Good morning. I am off to Boston for a bit of a Medical Procedure; here is a sequence I wrote up.
Maintaining a good vacuum is key and one tip is to use a bit of silicone grease on the threads of the Bleeder Valve screw in order to prevent or minimize the inherent aair leakage there.

Have a read and think it through. Ask questions. Check your set up. I'll be checking the forum remotely as I am able, then later today I can respond....or you can give it a go if you are comfortable.

Bleeding the Clutch

  • Protect area around Clutch Master.
  • Remove Clutch Master Lid.
  • Open new full bottle of DOT 4 Brake Fluid.
  • Prep your MityVac for service.
  • Put 8mm box-end wrench on Clutch Slave Bleed Fitting.
  • Crack Open then Lightly Close the bleed fitting.
  • Connect MityVac to Bleed Fitting leaving wrench in position.
  • Create vacuum in MityVac canister...see if it holds vacuum with no action. If it holds, proceed. If it doesn't hold vacuum, then correct connection leaks until vacuum holds. (This step just makes it easier to maintain vacuum throughout the bleeding process.)
  • This is where co-ordination with your partner helps: Crack open the Bleed Valve while sharply actuating the clutch lever (have a rag covering the Reservoir as it can squirt fluid) and BEFORE releasing the clutch lever, tighten the Bleed Fitting lightly then release the Clutch Lever SLOWLY. (That is one BLEED CYCLE).
  • You can repeat BLEED CYCLES as many times as you need to refilling the reservoir each time so that you do not entrain air into the Master Cylinder.
  • Repeat the cycles until there is no more air and you are certain you have clean fluid throughout.
  • Top off the Master Cylinder.
  • Now, with rags to catch the runoff, CRACK OPEN the Banjo Bolt at the Master Cylinder, then slowly actuate the Clutch Lever. At the end of travel, tighten up the Banjo Bolt connection then, SLOWLY release the Clutch Lever.
  • Now for a little "trick": Sometimes there are bubbles that simply will not move through the system for bleeding. These bubble tend to get trapped in the Master Cylinder itself and can cause a spongy lever. To remove these bubbles you need to TAP the Clutch Lever SHARPLY in the direction of actuation. This will cause fluid to move through the return passage and should release little bubble with each "tap" until clear. The "TAP" action is like spanking the lever in the actuated direction. Quick. Violent. A "Flick" if you will. With practice you will see it work.
 

·
Registered
Joined
·
906 Posts
Discussion Starter · #53 ·
SS,

To clarify, the banjo bolt at the master cylinder is on the left handlebar, by the clutch lever itself, correct? Not down low near the clutch fluid bleed valve?

Hopefully we can work your procedure and get my bike running again. This morning is out due to other business. Everything here on the Gulf Coast is on a heat clock. It will be over 100F today again, with very high humidity.

Sincere thanks and salute!
 

·
Super Moderator
Joined
·
25,536 Posts
Yes, you are correct. On the left handle bar.
Air collects there.
 
  • Like
Reactions: lucydad

·
Registered
Joined
·
906 Posts
Discussion Starter · #55 ·
Yes, you are correct. On the left handle bar.
Air collects there.
Ah I see, similar to the rear brake ABS banjo bolt: bleeding that resurrected my rear brake pressure.

Two last questions: I have Bel-Ray waterproof grease. Is that ok, or should I buy some silicone grease?
Also should I avoid the 8 mm Mini-bleeder tool, and just use a 8 mm wrench to turn/close the bleeder valve?
Does air get through the mini-bleeder tool perhaps?

Hope to try this tomorrow. If a fail I may have to find other options.

Thanks again, good luck with saw bones.
 

·
Super Moderator
Joined
·
25,536 Posts
Every connection you make has the potential to allow air in and reduce vacuum. I would try to use the box end and go direct to the fitting with the hose.
As for the Bel-Ray, that will be fine. You just need a stripe around the threads for a seal against air intrusion.
 
  • Like
Reactions: lucydad

·
Registered
Joined
·
513 Posts
I've got one of those mini bleeder tools and it works great. As long as it seals with the bleed nipple OK (which you can tell by checking it holds a vacuum before cracking the bleeder valve open as previously mentioned) it is exactly the same as a wrench and direct pipe connection, just in a neater package which means you don't need five pairs of hands.

They're neat and make it easier and shouldn't cause problems, but it is all about a good seal on the bleed nipple. If you can't get a good seal with it then don't waste your time with it and just use wrench and tubing.
 

·
Registered
Joined
·
906 Posts
Discussion Starter · #59 ·
Every connection you make has the potential to allow air in and reduce vacuum. I would try to use the box end and go direct to the fitting with the hose.
As for the Bel-Ray, that will be fine. You just need a stripe around the threads for a seal against air intrusion.
SS,

Ok we tried again. I had difficulty getting a seal between the vacuum bleeder tubing and the nipple. The grease made the tubing slide right off. So grease off, and tube on. Did not try little bleeder wrench.

We carefully did the bleed procedure. When applying vacuum, nipple closed, there were a few slow bubbles. Maybe try a smaller diameter hose than came with vacuum system?

How much vacuum to apply?

We did the bleed maybe twenty times, hopefully getting some air out of the system. Then then banjo (significantly stiffened clutch lever), then the sharp final lever whacking while not tipping the bike over.

Clutch seems to feel more normal, not mushy as before?

Tomorrow morning, when it cools off, I will start the bike and see if it will go from N to first, and first to N in the garage, if that works ok, I will roll it out for a short ride and hope for the best. Heat index over 100F already.

Advice?

thanks
Greg
 

·
Super Moderator
Joined
·
25,536 Posts
Sounds like you have it licked.
The little bubbles are to be expected.
Grease should only go on the threads in the future.
After your short ride, if you are still a bit spongy, I would do the banjo bolt again.
 
41 - 60 of 62 Posts
Top