Was cleaning the chain this morning on the 2001 M600 and noticed a circle where the sprocket retaining screws rubbed the front sprocket cover:



I hadn't noticed it before, but it's possible the rub was there even before I bought the bike; this is the first time I've done a really thorough job of grubbing out the area around the front sprocket.

The sprocket has 1mm or less of lateral play along the output shaft (which doesn't move) -- enough to feel, but not much more than that. I checked the retaining screws & they're both good and snug. The sprocket itself looks to be in great shape, though I'm just about due for a new chain & sprockets anyway -- want to go to 14T, and the parts on the bike now have at least 6K miles on them, so it makes sense to replace them all together. Though I didn't think to pull out a straightedge before I put the cover back on, just eyeballing it I could convince myself it's bowed inward just a little bit.

Anyway, is the rub mark on the sprocket cover or the tiny amount of lateral play in the sprocket anything to be immediately concerned over?

Did you take off the retaining plate and have a good look at it?  They wear out over time.. that might be your culpret

Good idea; I didn't do that, but might be worth a quick look while I've got the tools out.

Thanks.

I honestly could be wrong here, but I always thought that most (if not all) Ducati front sprockets were supposed to "float" a little bit. To do that to your sprocket guard, though, is too much I'm guessing. 

Did I dream this up?  I could have sworn they were... 

Quote from: johnster on July 29, 2008, 01:19:06 PM
Did I dream this up?  I could have sworn they were... 

I think you are...  There might be a tiny bit of play due to the different in the thickness of the retainer plate vs the width of the grove it sits in.  But we are talking fractions of a mm.  And to wander all the way over and run on that cover is like a cm or more...

Most of them have a little wobble to them (float?). I've been working on a full floating front sprocket but haven't been real happy with what I've come up with yet.

Norm,

Why would a person want this? 

To eliminate chain bind and let it move around a bit? 

Quote from: Norm on July 30, 2008, 08:51:24 AM
Most of them have a little wobble to them (float?). I've been working on a full floating front sprocket but haven't been real happy with what I've come up with yet.

All normal don't worry about it, the rub mark is just from grit that gets dragged up in to the cover.

Take a look at this keeper, notice the wear on the teeth, this increases the axial clearance.



BTW, the rear sprocket on the S*R's also has some float and wiggles.