could filling with too much oil cause a leak?

[hydra]

okay here's the results after a 10 mi run.

no change at the breather valve, so it's obviously not coming from there.

what do you think speeddog? it could be that the base gasket is indeed developing a leak. i'll be doing some errands on the bike today and i'll keep an eye on it. i'm going to call you in 5 mins...

[Speeddog]

The oil gallery is where I've drawn the red line.
It actually doesn't continue up into the cylinder, but that's what the boss is for.

The brown stain that's spreading to the left of the line indicates to me that it's leaking from the gallery.

[hydra]

The oil gallery is where I've drawn the red line.
It actually doesn't continue up into the cylinder, but that's what the boss is for.

The brown stain that's spreading to the left of the line indicates to me that it's leaking from the gallery.

hey speeddog, i don't see the pics...

[Speeddog]

Sorry, it works better if I actually *attach*  the pic. 

[hydra]

right!

"bill in PKC" pm'd me with this info:

A base gasket leak can happen if your crank breather valve goes bad.  Check to see if the reed valves are fractured or stuck open.  If the valve isn't working properly excess crankcase pressure from blowby can make the base gaskets weep.

what do you think?

[Speeddog]

If the breather valve was plugged, and not letting air flow, maybe.

[clubhousemotorsports]

The boss that speeddog has highlighted is the feed to the head. ducati had a problem with sealing this area on some bikes. If you pull the cylinder I would bet that you would find that that is where the leak is coming from. On 4valve motors the feed ends at the cylinder as the 4 valve motors do not use a feed through the cylinder like the 2 valvers do.

If the leak is not bad you can keep it clean and live with it for a long time. If it is pooing enough to get on a tire or the brakes you should really fix the problem.

Something else to check would be to make sure you do not have a pin hole in a hose or your breather box.

my .0002$= base Basket

[Zipper]

Bike: 2002 S4
Miles: ~4,300

This weekend, I had (nearly) the same thing happen to me.  After riding it home from the dyno-tune / custom map I put it in the garage.  About 30 minutes later, I noticed candy apple red silkolene dripping down my kickstand originating from some small reservoirs above the crank shaft.  Having just spent $250 on a custom map, I was sorely dissapointed to realize that i might have a bad gasket.    I have always been careful not to overfill so I know that was not the case.

A failed gasket at 4,300 miles is a real kick in the pants, particularly when I don't ride (that) hard...

I'll keep you posted with what I find.  This information above was helpful in suggesting what I suspected.

[Speeddog]

From what I've seen, the base gasket starting to leak hasn't had any correlation to how hard you ride.

[clubhousemotorsports]

Zipper before you go pulling things apart to do a bas gasket clean every thing real well and spray it down with a aerosol foot powder. then run the bike and look for the origin of the leak. A custom PC map takes a lot of runs and some at high rpm you may have forced a leak else where. could be the breather itself,breather box,lines,etc.

May be the base gasket but  rule the rest out first.

[Pancake81]

I am pret sure he has already covered that.

[Zipper]

Thanks everyone above.  I finally had some free time this am to clean everything down, and spray it down with some foot powder.  I went out for a short ride (15 minutes or so) and the oil leak become visible again.  I took a few pictures, but am curious to other opinions? 

1. Everything cleaned off:

2. Post Ride:

3. Does this look like the base gasket failed?
4. Any other suggestions / thoughts.  The closest dealer to me in central NJ seemed to think a base gasket replacement could run anywhere from $300-$800. 
Thanks in advance for any ideas / thoughts
Zipper

[Speeddog]

1. Excellent job getting it clean. 

2,3. Yes, that looks like a base gasket leak.

4. It's not really a base gasket *replacement* that's necessary.
The base gasket is really a metal shim, and it depends *completely* on the liquid sealer applied at assembly to hold back the pressurized oil in the gallery.
That's why it doesn't always work, because that's a lame thing to do.
Previously, ducati used an O-ring to seal that gallery, which was the proper thing to do.
The gallery needs to be plugged.

I'd expect the price to be toward the upper end of the 'window' they quoted.

[clubhousemotorsports]

+1 good pictures that is defiantly the base gasket. As long as the leak is not getting on the tires it is not a safety issue. Probably loking at 4-5 hours to re-seal the base gasket and on a 4 valve I would  the galleyway in the cases as it is not used to feed the heads.

[Zipper]

Speeddo and Ducvet, thank you for the responses. I'm brining it into the shop on Tuesday and will post the final diagnosis and cost for others who might run into this problem down the road.