S2R 800 clutch damage

[Speeddog]

Would I be correct in thinking that if the Cush drive was being damaged, that pieces of Metal would show up on the Sump plug? I change my oil every 3000 km. and the amount of metal on the Sump plug is very minimal (normal wear and tear)

I would think so, but it only helps *if* you happen to catch it before it fails completely.

[ducpainter]

<snip>
I have a question, what is the difference between red and blue Locktight? Also I'm not so sure Locktight is even going to be effective in this application… Prob is that the primary shaft is splined, so instead of the compound being buried deep betwixt threads of nut and shaft -like for example mortar buried deep within walls of a building… it will be in a point contact like situation between these raised lands of the spline's and the thread of the nut.  Might one type of compound work better than the other?

Blue locktite is removable with normal hand tools. Red requires heat/impact tools to remove.

The splined end of that shaft is probably the reason the nut is loosening. They've cut the thread surface in half. The locktite will still work on the threads. You don't need much, and red is what you want for that application.

[CairnsDuc]

I would think so, but it only helps *if* you happen to catch it before it fails completely.

Ah, no worries, I have ordered a Torque wrench with the setting high enough for what the service manual states for the Torque setting, When it arrives, I shall break out the Tools (Plasma cutter, large assortment of hammers, Medical Kit, Etc) and have at the Clutch.

With nearly 24000 Klm's on the bike, it will be interesting to see how tight the nut is.

[Lord_Bragle]

I had a right game getting my clutch back together. I made a big kikass tool to hold the outer drum but when I stuck the big central nut on to the primary shaft it just turned round and around.  I had to use three long thin 3mm pins plus spacers placed where the Ducati Tool used for installing the three helper springs go, these clamped up the plates enabling me to torque the nut up.  Beware anyone removing that big nut because you do need some special tools to get it all together again.

Something else about the primary drive on these bikes is that there's a shock absorber built in to the gear on the end of the crank, its got a strange nut holding it on too, doubt a tool could be made for this, it will have to be a genuine service tool me thinks 

[Dave328]

Nice little tool you rigged up there! 

[Lord_Bragle]

Little tool ! lol

[CairnsDuc]

Well, I pulled the clutch apart on my S2R 800 tonight and checked the nut, rock solid, I damn near ruptured my Ass getting it undone, now because I didn't have the Ducati tools to hold the clutch plates in place I removed them making sure to keep them the right direction and in the same order they came out!

I didn't remove the nut completely, I loosened it enough to turn by hand, moved it out on the thread while holding the centre part of the clutch, gave it a quick wipe and clean, dropped on a little Loctite Red, and re-secured the nut to 140 Ft pounds.

I have taken a number of photo's and I'll put up a basic Tutorial, but it's nearly 1am here in Australia, so I'm off to bed (been up since 5am )

Now I know how to do this I might make it a part of the 12000km service, granted the Loctite red should stop it, but never can be to careful!
We all know how much expensive damage this nut will cause should it come loose!!!

[BK_856er]

Sorry to bring up such an old thread, but there is lots relevant info above.

I'm getting ready to reinstall the APTC wet clutch in my M695 (new plates, springs, shift detent, etc.).

On disassembly, the large clutch securing nut was barely more than finger tight.  I think I dodged the bullet on that one!

I have the option of using grease on the nut (the Ducati way) or going with some thread locker.  Given the history here, I'm inclined to use thread locker.

Should I be concerned about not achieving the same clamping force due to the lack of correct lubricity of loctite relative to grease?

I want to make an informed choice on the loctite formulation.  They are not all the same, even if the color is, and the environment is pretty hostile.  I reviewed numerous Loctite Technical Data Sheets.  Ducati calls for "Locker 5" on the flywheel side, and apparently also on the clutch side of some SBKs.  This corresponds to Loctite 128455, which is formally a retaining compound as opposed to a thread locking compound.  But, it has quite exceptional temperature/oil/shock resistance.  I checked with Henkel, and Loctite 648 is essentially identical and can be obtained locally.

Anyone see a reason not to use Loctite 648 (green) on the clutch nut and torque to the usual spec?

BK

[jerryz]

On Dry clutch models Ducati raised the torque value for the Clutch nut to 136ftlbs over the years from 122ftllbs to 130ftlbs etc as they had a tendancy to back off , my S4 clutch did that when I first had it .I have an electric air wrench for undoing Ducati clutches and holding tools but I always use a hand torque wrench when retightening for accuracy and sensitivity and new tab washers and red loctite .Last 4 years never had a problem with any Ducati I worked on with these methods .

Check what the current value for the ATPC clutch torque is I bet Ducati has raised it ...

[BK_856er]

The more I think about this particular application, the more I wonder if loctite would even adequately cure, given that the threads are cut into the splines of the shaft and there are only mm of individual discrete contact areas.  Would make it very difficult for the necessary "anaerobic" conditions to exist over much if any of the metal/metal interface.  Maybe that's why the factory does not bother with thread locker?  My brain hurts.

I did check with my dealer about updated procedures or specs, but they were not aware of any.

BK

[rockaduc]

I would say go for the thread lock...but then again, you can fit what I know into a thimble and still have room left.

[caperix]

A lock tab for the nut off a non APTC bike would be good insurance.  Never could figure out why Ducati did not use them on the APTC bikes.

[BK_856er]

A lock tab for the nut off a non APTC bike would be good insurance.  Never could figure out why Ducati did not use them on the APTC bikes.

Not sure there is enough access to deal with a lock tab.

Looking through my 749S service manual, I see that Ducati also specifies grease for the (dry) clutch nut and also the front sprocket, which uses a threaded/splined shaft like the wet clutch on the M695.

I sent some photos to the tech people at Henkel (loctite) and they thought that the 648 would probably cure just fine in the threaded portions, but a two part epoxy thread locker would be preferred.  I'm going to do the following....grease the inward 2/3 of the shaft with moly grease, and apply loctite 648 to the outer 1/3 of the nut...then torque to the high end of the spec with 200Nm.  Hopefully that gives me the designed lubricity/clamping and also some degree of "insurance" with the green 648.  Will plan to check every 10k miles or so.

BK

[Roaduser]

i have an 03 800 dark and have noticed a slight increase in handlebar vibration out of gear with no clutch. i pull the clutch and the vibration lessens. also the other day, twice, on hard launches the clutch seemed to slip a little with kind of growl sound/feel.. can anyone tell me if the 03 800 had this same slipper clutch as the s2r or was it only 04 and on that had it.

Cheers Clint

[Howie]

Your '03 should have a conventional wet clutch, but the nut can loosen on those also.