860GT flywheel pinion washers

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rjk40
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860GT flywheel pinion washers

Post by rjk40 » Sat Jul 07, 2018 10:47 am

To the League of Fine Gentlemen:

I'm really showing my ignorance on this question:

Two rather thin and narrow washers, p/n's 0755.47.050 and 0755.47.060 , which are 0.2 and 0.3 mm thick respectively, as shown in the 860GT parts manual crankshaft assembly picture, sit behind tab washer p/n 0755.47.095, which is held by the large nut, and which is bent over a nut facet once torqued into place. This is at the crankshaft pinion gear/timing/flywheel assembly on the left side of the engine, and which drives the clutch basket.

The purpose of the two thin washers is not clear to me, since they sit behind the tab washer and against the face of the pinion gear. They do not seem to establish any critical clearance, thus I do not understand their purpose, unless it is to provide a "cleaner" thrust face between the tab washer and the pinion gear, since the tab washer is of fairly rough stock, and could be distorted by the bending act.

Anyone care to help allay my ignorance? If I've missed a Forum entry on this topic, I apologize.

Thanks in advance.

Richard in Malabar, Florida
(sitting in the dark, feeling like a fool for having to ask this lame question).

rjk40
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Re: 860GT flywheel pinion washers

Post by rjk40 » Sat Jul 07, 2018 11:38 am

Correction!

Now I'm really confused. The washers I mentioned on the previous post are approx. 0.35 mm inside diameter and .43-.45 mm outside diameter. Clearly, These are not the ones that I found behind the pinion tab washer. When I ordered them, I thought I was ordering replacement for the ones behind the pinion gear, but that was in error. I am guessing that they go somewhere else on the crankshaft. I have not taken any rotating parts off of the right side of the crankshaft, as I see no need to, but am now wondering where these two "other", smaller washers go. They have in inside diameter of about 20 mm and an outside diameter of 25 mm. They do not have sufficient inside diameter to fit behind the tab washer, as I originally thought, and I was confused by the crankshaft drawing showing the two washers I mentioned in the last post (0755.47.050 and 0755.47.060 appearing on the same side of the crankshaft as the pinion nut (ducati 860GT parts Manual, page 23 of 83. Now, I am not sure where these two smaller washers go. The only place they seem to fit is outboard of the pinion nut on the unthreaded part of the crankshaft, the part that mates up with the clutch case cover/bearing. That bearing is still in the clutch case cover, and spins as smooth as silk, so there is no need to replace it; perhaps these two little washers fit on the crankshaft just inboard of the bearing. It has been two years since I took this thing apart, and I am kicking myself for not doing a better job of documenting.

I began to be suspicious when I saw your collective comments about re-installing the flywheel/pinion gear and did not see these two washers in the helping hints. They will not fit on the threaded part of the crankshaft right side, where the tab washer goes, as their inside diameter is too small, and I misled myself with the Parts Manual drawing. At best, I will re-install the pinion/flywheel assembly with only the tab washer and nut, and hope that I find the right home for these two mystery washers.

Any help is humbly appreciated. This is, so far in this resto, the first time that I have managed to stump myself.

Thanks in advance.
Richard in Malabar.

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Craig in France
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Re: 860GT flywheel pinion washers

Post by Craig in France » Sun Jul 08, 2018 3:33 am

Hi Richard,

As I think you've worked out ;) , 0755.47.050/060 are thrust washers that fit on the end of the crank, inside of the left crankcase, to take up any end float in the crank when it's installed in the crankcases.

As for your mystery washers, I don't recall there being anything sitting on the end of the crank outside of the pinion nut (In fact, I can't see what ''job of work' it would be doing. Instead, it would most likely block oil flow to the bearing in the clutch cover :doh: ...).

Going by size, I suggest that one (at least) might be the spacer that goes behind the clutch centre, part # 0022.84.035 ? However, this was only required up to engine #851193. What engine number are you?

Image

HTH

Craig

rjk40
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Re: 860GT flywheel pinion washers

Post by rjk40 » Sun Jul 08, 2018 5:18 am

Hi Craig,

Thanks for the info; isn't that giant beginning to sag under your weight on his shoulders?

My engine's number, as stamped into the case at the rear, is 851539, well above the threshold.

I shall look at things more closely, thanks to your illustration. As it's been quite a while since the original disemboweling of the left side workings on the engine, I wouldn't put it past myself to have put these pieces in the wrong pile of entrails spread about my workbench. You are most likely spot on target on where these two this shims/washers go.

The crank washers I bought won't be used anytime soon. The crank has no side play, and turns smoothly. I have had no need to split the cases, nor do I want that.

Thanks again for the info; you and the League are most appreciated.

Regards,
Richard

rjk40
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Re: 860GT flywheel pinion washers

Post by rjk40 » Sun Jul 08, 2018 12:30 pm

Hi Craig,

Another issue on this bike, one that has existed since I bought it new: when leaving from a stop in first gear, the clutch was extremely sensitive to chattering, unless I finessed it (not possible when leaving quickly) and remembered to hold my mouth right as well when engaging the clutch(humour…). It was a mystery, and one shrugged by the dealer who said that it was common, and to just live with it.

It's hard for me to believe that the clutch should be that chattery without the possibility of a fix; perhaps the washer (s) you mentioned are part of the problem and should not be there in my 851539 engine.

Time will tell.

Regards,
Richard

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Craig in France
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Re: 860GT flywheel pinion washers

Post by Craig in France » Sun Jul 08, 2018 10:46 pm

Does seem strange, Richard. I haven't heard of anyone complaining of clutch chatter on a 860 before.

After 851193, both the clutch centre and the basket carry different part numbers, so it seems that both were modified. But I don't know what those changes were - you'd probably need to have the parts in your hand to tell.

I think you're right: assemble things carefully, paying particular attention to how things mesh. As you say, it may be that you don't need those washers ...

rjk40
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Re: 860GT flywheel pinion washers

Post by rjk40 » Tue Jul 10, 2018 6:48 am

Gentlemen:

Now this is getting really confusing.

Craig, the washer you pointed out in the drawing sits between the clutch "basket/housing" and the clutch "drum" (the smaller unit that fits inside the drum and has five spline teeth). That being the case, the part number listed, 022.84.035, in the parts manual, is a washer with the dimensions of 25.5mm x 22 mm x 1.5 mm. Here, it gets weird for me: the splined shaft area where this washer apparently resides has a diameter of approximately 25 mm, which is the larger of the dimensions listed on the washer. With that said, the other dimension is 22 mm, which means that the washer listed will not fit onto the splined part of the exposed shaft, rather only onto the smaller outermost threaded part where the nut and washer go ( BTW, I purchased a "special" locking washer from Steve, that fits over two of the five protruding studs on the drum and is pre-bent to facilitate bending over a nut facet). Thus, either the description in the parts manual is in error, or I need mental health competence counseling. I have not found in my possession, the washer that you point to, which seems quite important because of where it sits, between housing and drum. What would be about right would be a washer with the dimensions of about 25.5 mm I.D. x 32+ mm O.D. x 1.5 mm thickness, something I have yet to find in my searches.

Per the mystery washers that I mentioned in the recent posts, which have dimensions of about 20 mm I.D. x 28 mm O.D. x 1.5 mm thick. I have yet to discover where they live.

I don't know what any of you might suggest, but at this time, if I can find the "right" washer to go between the two clutch pieces, I can move forward and who knows, mebbe the durned clutch will work properly when I get it together.

Regards,
Richard in Confusion (a small town in Florida)

rjk40
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Re: 860GT flywheel pinion washers

Post by rjk40 » Tue Jul 10, 2018 11:07 am

… and, to make matters even more confusing to me, the clutch drawing that Steve posted under the topic Clutch pushrod info shows the clutch for the 900 , which does not have the said washer #35. The mystery grows.


Somewhere, there has to be either an answer or a mental health specialist (besides the wet bar....) who might shed light on the proper config.

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Craig in France
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Re: 860GT flywheel pinion washers

Post by Craig in France » Fri Jul 13, 2018 9:47 am

Hi Richard,

1. Washer 022.84.035:
Your engine number being 851539, you don’t need it (see my earlier post). Look at the drawing below and compare it with the one for the earlier engines. You'll see the washer just ain't there no more ;) . So forget it, put it out of your head, assign it to oblivion, it never existed …

Image

2. Your mystery washers:
I too am unable to find a home for them. So my advice at this time would be to put them in a ziplock bag marked “? Unknown from clutch side” and continue to assemble the rest of the engine paying careful attention to fit and mesh.

HTH

Craig

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Re: 860GT flywheel pinion washers

Post by rjk40 » Fri Jul 13, 2018 10:36 am

Hi Craig,

Thanks kindly for the comments.

I came to the same conclusion, since my engine serial number of 851539 is above the threshold, and went ahead and assembled without the washer (which I didn't have anyway). I am putting the matter to bed and will forge on, bagging the mystery washers and tagging them as you advise.

I am praying that the clutch will work properly when assembled, but I have mucho to do before I reach the point of testing it. I will soak the clutch disks/plates in Motul oil for a day before installing them.

I am now going through the oft-covered issue with new clutch pushrods. I ordered a full set from BH, the long rods out of the bike are a bit rusted and cleaned up nicely, but while I am in the entrails, it just makes sense to put new parts in as long as my wallet and health are still upright, so to speak. I am not going to belabor the old topic of pushrod configuration, and will use my best judgment. There are many variations on pushrod group configurations, and I will digest the Forum info and hope for the best. I have polished the hole in the clutch actuator arm, as it was quite rough, and hope that the rounded rod end will be happier in its smoother home, especially with some good grease, both there, and on the pushrod "train".

I am now waiting for a plastic piston stop (one that cannot hurt the piston top) to find spot-on TDC when I time the new Sachse ignition. Test rotation showed good results looking at the LEDs on the timing sensor plate. I don't know if my unit has the cylinders' connections backwards on the ignition module or not (per previous posts...), but if so, my right leg will eventually find out, and it is easy enough to switch at the module if I still have two good legs to stand on.

Best Regards,

Richard

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Craig in France
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Re: 860GT flywheel pinion washers

Post by Craig in France » Sat Jul 14, 2018 12:34 am

rjk40 wrote:
Fri Jul 13, 2018 10:36 am
There are many variations on pushrod group configurations <snip>
This is at least partly down to minor changes that Ducati made to the crankcases over the course of production. One of the reasons you have that train of bits is to compensate for any slight differences in the mating of the crankcase halves. Otherwise the clutch pushrod tunnel would have had to have been bored after crankcase assembly - impractical, time wasting and expensive. (It was Tony Brancato who explained that to me, btw).

So my advice would be to use the sequence that is 'right' for your engine number, i.e. that matches your cases and the components they house.

Be confident: these clutches work well. Problems are almost always down to abuse or incorrect assembly.

rjk40
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Re: 860GT flywheel pinion washers

Post by rjk40 » Tue Jul 17, 2018 12:35 pm

Hi Craig,

Here is a link to a pic showing clutch rods et al:

https://www.flickr.com/photos/124760992 ... ed-public/

The pieces sitting on the balsa rail are the old pieces in the order of removal; there are TEN pieces (TEN pieces; REALLY?). You can see a bit of surface rust on the long rods, but no damage, galling, etc.

The pieces directly on the blue towel are the new ones from BH. There are eight pieces, and their total length is slightly less than the length of the ones I retrieved from my engine, even though the new one that fits into the clutch lever is longer than the old one; no great surprise as my old ones have an extra small roller ( ???????, or WTFO?), and are not an exact matching lineup for any drawing in the parts manual, as none of them have ten pieces. The "newest" config has eight pieces, and the older two both have nine, the difference being one less small roller between the two long rods.

My best guess will be to put all of the new pieces in, per the "newest" drawing in the manual, the one for my 851539 engine.

I'm really wondering what went on at the factory, since I bought this bike new from the dealer in Tulsa, Oklahome (Atlas Cycles, now out of business).
Mayhaps a trainee was assigned to install the durned rods; maybe that happened after a long Italian lunch hour.

If the original configuration was too long because of the extra small roller, I am unsure whether that was just adjusted out (if that's even possible...), or if it could have been the cause of the chatter.

Regards,
Richard, still somewhat confused in Malabar (small town in Florida)


Anyways, I will install the new rods per the drawing for engines above # 851194, and hope for the best, and try to ignore what was put in by the factory.

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Craig in France
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Re: 860GT flywheel pinion washers

Post by Craig in France » Tue Jul 17, 2018 10:58 pm

rjk40 wrote:
Tue Jul 17, 2018 12:35 pm
My best guess will be to put all of the new pieces in, per the "newest" drawing in the manual, the one for my 851539 engine.
Agree, Richard. The critical thing is that your push rods match the rest of the clutch assembly. And at this stage, without evidence to the contrary, you have to assume that all is 'as it should be' :?
rjk40 wrote:
Tue Jul 17, 2018 12:35 pm
The "newest" config has eight pieces, and the older two both have nine, the difference being one less small roller between the two long rods.
Small correction :) . ONLY the pre-851194 engines had 9 components. Post-851194 has 8; and a quick check shows that this configuration continued to be used on the MHR and the Darmah.

FWIW here's a check list of the bits with their sizes. Note that the roller and ball dimensions are in inches :) .

Image

Btw, once all is in place, you can of course do a basic check on the operation of the clutch - i.e that the plates are separating - before going any further.
Last edited by Craig in France on Thu Jul 19, 2018 3:11 am, edited 1 time in total.

rjk40
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Re: 860GT flywheel pinion washers

Post by rjk40 » Wed Jul 18, 2018 4:48 am

Craig,

Thanks as always for the good info, and especially for the dimensions of the clutch pushrod pieces.

Regards,
Richard

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