s2r 800 clutch slipping? or just weird aptc clutch action i cant tell, help!

[reverus]

First, I did the search both here and other forums and can't find what im looking for, people talk about how the aptc is weird but don't really expand beyond that.
here's what's going on,

I've had my duc for about 3 months now, i always noticed the clutch was odd but just chalked it up to getting used to an italian bike since all i've owned is honda.
The bike has 14k miles on it. 
A few days ago, I took her on her first long ride, 200 miles through the mountians with a really long strait stretch at the end. On that stretch (we're talking flat, empty, smooth, no cars, no houses, no nothing) Me and my friend kicked it up to about 110 and just held it there for like 15 minutes. maybe 20. when we got to the end of the stretch there was an onramp to get back on the main hiway, I nailed it going up the ramp and had a really really weird clutch thing happen,
The bike was pulling fairly smooth but the revs were lurching,  after i would slam the next gear they would climb, bog, then settle and pull. I thought for sure i roasted my clutch. we still had another 30 minutes or so to get home so just went on like normal. no issues from the clutch to speak of other than some grabbyness at launch, I chalked it up to heat and assumed if they were mildly slipping durring that 110 mph strait i must have gotten them extreemly hot. The next day i took her out and tried to abuse the clutch some (letting it out hard and fast between gears instead of my normal clutchless shifting) to see if the clutch was damaged or if it was okay, Now it's riding fine, but it sounds different.. or maybe im just oversensitive now.. i can't tell, I took my rc 51 out between issues with the duc and i think i messed up my referance to what it should sound/feel like. I'll put it like this..

rc51 clutched shifting:

baaaaaaaaaaa-BAaaaaaa-BAAaaaaaaa    each gear catches hard.

s2r shifting

BaaaaAAAAAAAbbbbaaaaAAAAAAAbbbbAAAAA     no "catch" between gears, just sort of a glide.. i guess...       

question is, does this sound like normal weird aptc stuff, or are my clutches going out, I dont wanna find out they are trashed 400 miles from home...
sorry for the ridiculous post, this is hard to describe in text.

using fresh silkoleen 10-40 4t full synthetic just changed last month.

thanks

[stopintime]

IME, when a clutch is worn, it's beyond doubt - slipping occurs at full torque (full throttle at ~6-7,000 revs)

What happened could very well be heat/abuse related. The following grabbiness could be because of cooked and glazed discs. If it doesn't become better, maybe they're damaged beyond self repair.

Speeding in itself shouldn't impact the clutch much - maybe it was slipping a little...

[BK_856er]

My APTC clutch is very sensitive to oil type, even within the "moto specific, wet clutch safe" category.  The oil that works the best for my APTC is Mobil 1 Racing 4T 10W40.  Whenever I've used other stuff I've had issues like you describe at max torque.  Eventually not even my favored oil could tame the clutch, so I replaced the plates and springs.  I think that was at about 20k miles, but not certain.  Worked great after that and still does.  With the side cover off I also discovered (!) a hand-tight clutch hub nut, so I don't know if that was contributing.  Another member here used my old clutch plates in his bike apparently without issues - they weren't glazed or scorched or worn thin.  Try some Mobil 1 4T at your next oil change, bleed the clutch hydraulics and check the lever free play (you didn't change levers, did you?), and then think about verifying the torque on that big hub nut under the engine cover.  I've heard that some have shimmed the clutch springs with an additional washer to decrease slippage.  The Ducati plates are $$, so that's probably a last resort.

BK

[reverus]

I adjusted the lever (previous owner epoxyed over the adjustment screw... WHY?? so had to chisle that off...)  to what feels like about 1/4 inch of play, now, to be clear, that's 1/4 inch before resistance is felt, not 1/4 between the adjuster and the mc rod, those are contacting all the time is this correct?

I'll try switching to mobile one, what about semi syn? 

where can i find more about shimming,

what plates did you replace with? i was looking at the barnette kit. but i'd rather spend that on other parts,

[MV]

I'm in the middle of doing ours at the moment, clutch was slipping at 6K rpm when you gave it a fistful.

Good idea to whip the cover off & check the clutch plates, while your there, take the entire basket off & check the cush drive springs on the back of the clutch basket, they are prone to failure & make sure the clutch hub nut is done up, there have been reports of these being loose from the factory.

3 of the 6 cush drive springs were broken, luckily only 1 had exited the clutch, so not too much damage & lucky I caught it early, but I am up for a new clutch basket now.

[BK_856er]

Ducati epoxies the clutch lever adjuster at the factory after adjustment.  You must be very careful achieve the proper adjustment if you change levers or choose to alter the setting.  Lots of examples of insufficient free play at the lever causing clutch issues/plate wear.

I stand by Mobil 1 Racing 4T 10W40 for my particular APTC unit.  Key thing is that the APTC is particularly sensitive to oil type.

I chose to use Ducati (Adige) replacement plates.  You'd want to research the Barnett option for this specific application.  Not sure it's a good choice.

Search some keywords here for examples of APTC spring shimming to combat mild slippage.  For peace of mind I replaced my springs and shims along with the plates.

BK

[reverus]

thanks everyone, lots of stuff to check

MV,  did you have any noise from the broken springs or other signs of failure?

also, before i tear into this, do i need a gasket for the side case

[BK_856er]

The Ducati way is Three-Bond grey sealant or equivalent on the engine covers.

CA Cycleworks has an awesome paper gasket.  If you have to go in multiple times it's super convenient.  I use one.

BK

[brad black]

I adjusted the lever (previous owner epoxyed over the adjustment screw... WHY?? so had to chisle that off...)  to what feels like about 1/4 inch of play, now, to be clear, that's 1/4 inch before resistance is felt, not 1/4 between the adjuster and the mc rod, those are contacting all the time is this correct?

I'll try switching to mobile one, what about semi syn? 

where can i find more about shimming,

what plates did you replace with? i was looking at the barnette kit. but i'd rather spend that on other parts,

epoxy is ex factory to stop people screwing it up later.  best way to check is to take the cap off the reservoir and pull the lever in.  do it gently, as fluid should push up if there is enough free play.  pull it in quick and it'll spray out everywhere.  if there is no fluid pushing up, wind out the adjuster until there is.  generally if the bike has got this far it'll be ok, but i did a fluid change on an 888 sp4 last week and that caused an issue.  23 years old, lever still gooped, not enough free play, but it allowed a fluid change.  wacky.

generally wet clutches don't wear out, they go off.  so they'll look fine, but will slip.

the broken basket springs on s2r800 are not uncommon.  not always a noise signal.

[MV]

thanks everyone, lots of stuff to check

MV,  did you have any noise from the broken springs or other signs of failure?

also, before i tear into this, do i need a gasket for the side case

No mate, just lucky I found it while I was replacing the clutch plates.

[reverus]

that's scary lol

[reverus]

Okay i have a plan of attack, I'll order some upgraded springs, and change to mobil1 at the same time, while im there i'll inspect the frictions ect.
Hopefully some stiffer springs and the oil change will fix it. 

sugestions on upgraded springs?  are the barnett springs stiffer?

[BK_856er]

You need to get the springs from Ducati unless there is some new aftermarket option I haven't seen yet.  The springs are unique to the APTC clutch.  It's not like a regular dry clutch pressure plate spring where you can go to various sources and get different types.  The trick with the APTC (so I've read) is to pretension them more with a thicker or additional washer.  While you're in there it wouldn't hurt to install new springs instead of reusing the old ones - just to make sure they're full strength.  There is a height spec, but I don't know how accurate that is to establish weakness.  Also check the torque on the large hub nut - they like to come loose over time!  Please also familiarize yourself with the workings of the APTC setup before you dive in - there are some additional parts you might need to be aware of.

Honestly, I would just bleed your clutch and verify the lever adjustment and try the M1 4T oil as a first pass.  It's a nuisance to pop the side cover and as brad pointed out the plates usually look and measure fine even if they don't work right.  Second pass could be disassembly and spring tweakage.  But that's just me.

BK

[reverus]

So I changed the oil today, I'm starting to think my oil may have been contaminated maybe by condensation, something I forgot to mention earlier, when I got the bike there was this odd looking "smudge" on the inside of the oil level sight glass. Like condensation only it didn't go away when it was covered by oil, like it was somehow between the outside of the sight glass and the oil itself. It's not there anymore. Also, there is a brown substance in the oil itself, it swirls when disturbed then quickly settles. This oil is only a few weeks old. I thought metal shavings at first but it doesn't sparkle, and the plug magnet wasn't abnormally Coated with shavings. I took a video. This is also a fresh oil pan.

[reverus]

Seems to be much better now, but I won't know for sure until I get it out on a long trip