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Hi I have a Ducati Monster 1200, when I was riding, I've seen that the level of the clutch liquid deposit was a little low. The level is between maximum and minimum so, this is normal?
 

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Hi I have a Ducati Monster 1200, when I was riding, I've seen that the level of the clutch liquid deposit was a little low. The level is between maximum and minimum so, this is normal?
Hi,
that is not normal, you probably have a leak somewhere,,... probably the clutch slave cylinder near the front sprocket.
Try to check for leaks around that area,...
 

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It’s normal. The level should not be at the maximum during warmer riding temps so the hydraulic fluid can expand.


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Hi,
that is not normal, you probably have a leak somewhere,,... probably the clutch slave cylinder near the front sprocket.
Try to check for leaks around that area,...
I was talking after my own recent experience,... fluid dropped, membrane as well and at first dealer also said it could be an expansion issue, but after shifting got more difficult they had a look and found out that the slave cylinder had a leak.

To me it's normal that the brake fluid levels drop, as brakepads wear out, but at the clutchside there is nothing wearing out so fluid kinda should stay the same, specially around this time of year as it is still not that hot,...
 

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It’s normal. The level should not be at the maximum during warmer riding temps so the hydraulic fluid can expand.


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AFAK, the volumetric expansion of both DOT 3 and 4 brake fluids (and mineral oil in Magura KTM clutch MC's) is very small and not enough to affect function of the clutch (or brakes, and your brake side will get much hotter than your clutch side) even when the fluid level is at the maximum mark. That said, do not overfill either reservoir, but as long as you don't exceed the maximum mark you will be fine. Air expands more than any of these fluids do, so make sure that each system is bled properly.
 

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FL living where sun is very hot and I commute as well as tour. Trusted independent mech says keep them 1/2-way so when the bike sits in the sun all day the fluids aren’t expanding to the point of leaking.

I believe he’s being conservative. But he’s seen his share of overfull reservoirs come in with fluid all over.


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I'm in SoCal and our temperatures are similar with less humidity. Track use tends to get the fluids pretty hot, and I've never seen overflowing reservoirs that were a result of hot temps (i've had Yamaha, Honda, KTM, and Ducati with hydraulic clutch MC's). Mechanical error, yes. Again, a good brake fluid has very little volumetric expansion (cheaper ones may boil off if you get them hot enough, and any air in the line will likely expand more than the fluid will). There is a little space above at the top of the MC reservoir that does allow for a little expansion. DOT 3 and DOT 4 are hygroscopic -- I imagine if there is too much moisture in your brake fluid, it would expand more than the brake fluid, but at this point, your fluid should be changed.
 
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If you're concerned about it just drop the slave and see if its got a leak.
If everything is a mess from chain lube clean behind the sprocket cover, refit it all and take it for a good ride and drop the slave and inspect again.
 

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I'm in SoCal and our temperatures are similar with less humidity. Track use tends to get the fluids pretty hot, and I've never seen overflowing reservoirs that were a result of hot temps (i've had Yamaha, Honda, KTM, and Ducati with hydraulic clutch MC's). Mechanical error, yes. Again, a good brake fluid has very little volumetric expansion (cheaper ones may boil off if you get them hot enough, and any air in the line will likely expand more than the fluid will). There is a little space above at the top of the MC reservoir that does allow for a little expansion. DOT 3 and DOT 4 are hygroscopic -- I imagine if there is too much moisture in your brake fluid, it would expand more than the brake fluid, but at this point, your fluid should be changed.
Good, good points, and experience.

The hygroscopic effect is magnified here by the very high humidity from May-Sept.


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Well, thank you guys for your advices. Finally call to my workshop, and they said that was not normal. So they revised my bike and they said that is was a problem of clutch pusher.
They will change this.
Thanks for the update,... it’s reassuring to have it fixed.
 
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