Hydraulic clutch reservoir low?

[TobyDanger]

So I though I noticed last weekend that the fluid in the sight window of my clutch reservoir was a lot cleaner than the fluid in my brake reservoir.  Upon taking a closer look it looks empty! 

Brake

Clutch


I can double check just by taking the lid off of the reservoir, right?  If it's fine, just cap it back.  If I do need to add fluid, can I just top it off with any sealed DOT 3,4 or 5 like the cap says, or does it all need to match what the rest of it is in there?  Should I bleed it as well?  The clutch control still functions really well.  And here I thought I liked these better than the pee cups...

Thanks,

[booger]

I took the clutch master off the handlebar and held it level to get an accurate reading in the sight glass. When I did this the level was above minimum which is what I have read is normal. Clutch works fine. If you top it off don't fill too much.

[scott_araujo]

That's probably fine.  Unlike the brakes where the fluid gets lower as the pads wear, when the clutch wears it actually pushes more fluid back into the reservoir.  Up to minimum on the clutch is just fine.  Keep your brakes topped up high, make sure there's at least some space in the clutch reservoir at all times.

Yes, you can just pop the top and see how much is in there.  Careful not to get any on the paint, brake fluid eats paint.

Scott

[He Man]

dot 3 4 and 5.1 NOT 5.

[Slide Panda]

Your probably fine - that window ret up really doesn't work since between the darkness of it being sealed and he lack of contrast if the fluids over the window.. you can tell 0.

As said NOT  DOT 5 - dot 5 is silicone based and you don't want to mix 3,4 or 5.1 with 5 if at all possible.  And it was oh so nice that they labeled that stuff 5 and 5.1 that's confused a ton of people

[ScottRNelson]

It's trivial to take the lid off of the master cylinder.  If it's down, the first question you have to ask yourself is where the fluid went.  The hydraulic clutch is not like hydraulic brakes where fluid is used to push the calipers as the pads wear.  If the fluid is down, you should have a look at the clutch slave cylinder down on the left side near the front sprocket.  You can pull it out in about a minute if you have the right allen wrench to see if it's leaking.

The last time I had a clutch slave issue, it was caused by a clutch throwout bearing that was going bad.  It was spinning the rod that the slave pushed to work the clutch.  The spinning destroyed the O-rings in the slave.  I had to replace my slave as well as the throwout bearing.  Throwout bearings are cheap, by the way, even from Ducati dealers.  Clutch slaves cost a bit more, starting at about $128 for a Ducati part up to about $180 for aftermarket slaves that change the leverage for an easier clutch pull.

[TobyDanger]

Thanks all, I'll be taking a closer look after work today.

[CairnsDuc]

And lets be honest here, The OEM Ducati Clutch slave is not of the highest Quality, I have customers who in are still in there 2 year factory Warranty and they are on there 3rd or 4th Slave cylinder.
The fine sand we have on the roads over here get past the Oring and score the original cylinder and then all of the fluid squeezes/leaks past and then no Clutch! Joy!

I get them resleeved with a Stainless Steel insert, never see them back again. (And a shit load cheaper than a after market Slave)