Transmission problem

[dafunk]

Hi guys,

I've been having shifting issues with my M900, it won't go below 3rd or above 5th.

Before I talk about what I think is happening, let me make sure I understand how the transmission works. Clutch fluid and transmission oil are 2 very different things. The first one is used to move the pressure plate when you press the clutch. The second one is used for lubrication inside the transmission, to facilitate shifting between gears (and for other reasons I'm sure).

Now, assuming this is correct, and assuming the glass on the left side of the engine is to check the transmission oil, I think I need to add some because I'm not seeing anything. Low oil would explain why it won't shift, and why moving the rear wheel seems to make it a little better (since gears eventually align).

Let me know if I'm completely out of my mind but if not, which transmission oil should I use? I can't find any information on it in the owner's manual!

Thanks!

Leo

PS: I've bled the clutch fluid.

[ducpainter]

The transmission runs in the same oil as the engine. You should not see oil in the left side window.

IT most likely has something to do with the adjustment under the left cover, or a bent shift lever

[dafunk]

Which adjustment are you referring to?

[Speeddog]

Which adjustment are you referring to?

Pretty sure this thread covers it:
http://www.ducatimonsterforum.org/index.php?topic=46039.0

Most likely one of the shifter springs has broken.

[dafunk]

Thanks for pointing me in the right direction, I found my problem :



This pin was moving freely back and forth. It moved too far out and was blocking the "wheel" from turning. Looks like it's supposed to be help by a clip, but I can't find it on any of the spare parts catalog diagrams. I've been specifically looking at diagrams 002 and 003 (M900 2002 PDF from ducati.com).

What am I missing?

[Speeddog]

Well, that's a failure I've not seen nor heard of.

The item that's responsible for holding those pins in place is 882.1.006.1A Needle retaining ring (square cross-section), item #16 on diagram 002.

I'm not aware of any way to replace that clip without splitting the cases, but I've never looked at the parts in that way....

[dafunk]

I also originally thought this was part 16 on diagram 002, but it is way too big. It would mean the "wheel" is part 19, and that part is labeled as a shim.

[Duck-Stew]

Well, that's a failure I've not seen nor heard of.

+1

[Speeddog]

The item you call the 'wheel' is #18, common parlance is 'shift drum'.

Item #19 is a shim that is used to adjust the lateral freeplay of the shift drum.

[dafunk]

Ah I see. What's the purpose of the retaining clip (part #16)? If I'm looking at this right, it's as big as the drum diameter and somehow also holds the pin (part #17). Why is that pin removable anyway?

I've been looking for an easy way to fix this but I really can't come up with anything. Putting the pin back with loctite probably won't help considering how hot the engine gets.

[Duck-Stew]

That's a side-to-side shim you're looking at.  The shift-drum needs these (of varying thickness) to account for machining tolerances of the cases & drum.

[Speeddog]

Ducati parts diagrams are not necessarily geometrically correct.
That shim is ~50mm diameter, but only 2mm wide.

The clip is actually a good bit smaller than the drum, and fits inboard of all 6 pins, sitting in the groove of each pin.

You can barely see the clip down in the bottom of the second from the right groove in this pic:

[dafunk]

Great picture, thanks.

How hard is it to remove that drum?

[Speeddog]

Engine removal and nearly complete disassembly to remove that drum.

[dafunk]

Well, I'll try loctite then. The high temp one I have can resist to temperatures above 400F. Since the engine runs around 200-250F, it might work.