damn front sprocket

[Speeddog]

Their isn't enough room in-between the sprocket and case to slip the chain off. I had to take the rearset off and slide the sprocket and chain past the case and then pull the sprocket. I had the chain completely off of the rear sprocket.

Key phrase for the 696/796/1100.

[matsoutback]

Well, I think I will go back to 15t front. Why? - Because I get this grinding "feeling" at my left ankle when coasting at slow speeds, ie when coming to a stop, clutch in. It feels like the chain is sitting hard on the plastic guide on the SSSA, near the front sprocket, and it is rubbing on that. I cant find an excessive amount of plastic or other material building up around the chain though...

It is a shame, because generally I find ridability 10x better with the 14t.

Does anybody else have that "grinding" sensation?

One more thing I noticed and I'm not sure if it is related to my issue, the 15t "factory" sprocket has a recess (about 2mm) for the mounting plate to bolt up to. This brings the teeth about 2mm further out from the mounting location.. ?

The 14t is flush from the teeth to the shaft, again, anyone else notice this? Bringing the chain 2mm closer to the bike. Am I being too anal about this, or could this be a real issue?

BTW, bike has 2200km on the clock and I did the 14t at the first 1000km service. It is 796ABS, MY2012

[Curmudgeon]

2mm off doesn't sound good. The chain link plates could be rubbing on the center rib of your plastic guide rather than just the pins resting on it. Sure you have the right 14T for that bike?! My Driven Racing 14T has the chain running correctly. Where did you get your 14T?

[matsoutback]

Would you be able to confirm if your original sprocket also has the recess I refer to?

The sprocket that went on was installed by my local dealer on the first service, and has a flush face. It matches the part number required, I did look it up at the time to check.

So, are the 14t sprockets people are putting on, flush or recessed?

[Curmudgeon]

Not sure what you're saying. My dealer installed this one. How does yours compare? http://motowheels.com/i-8051233-driven-light-front-sprocket-525-14t.html

[ungeheuer]

Well, I think I will go back to 15t front. Why? - Because I get this grinding "feeling" at my left ankle when coasting at slow speeds, ie when coming to a stop, clutch in. It feels like the chain is sitting hard on the plastic guide on the SSSA, near the front sprocket, and it is rubbing on that. I cant find an excessive amount of plastic or other material building up around the chain though...

If you put the bike up on a stand and spin the rear wheel.... can you hear/detect your grinding sound??

One more thing I noticed and I'm not sure if it is related to my issue, the 15t "factory" sprocket has a recess (about 2mm) for the mounting plate to bolt up to. This brings the teeth about 2mm further out from the mounting location.. ?  The 14t is flush from the teeth to the shaft..... Bringing the chain 2mm closer to the bike.

I'm sure a clue lies within the differences you've identified between stock and replacement sprockets....

Am I being too anal about this, or could this be a real issue?

If it were mine I wouldnt ride it until I located the source of the "grinding" sound....

It is a shame, because generally I find ridability 10x better with the 14t.

As do many others, myself (M1100) included for a while.  The issue is not the 14t sprocket in general..... but something awry with your 14t sprocket and/or installation by the sound of it.

I've subsequently dumped the 14t front in favour of 15/43 combo, but not because of any fitment issues with the 14t'er.

[matsoutback]

Thanks for the reply;

1. I can't hear any abnormal sound when free wheeling the rear tire when it is on the stand. 

2. The recess I refer to basically moves the teeth out beyond the mounting plate that 2 or so mm. I thought this was the problem too, so I ordered another 14t from Ducati (using their part number) for the 796, this sprocket did not come with the tapped screw holes to mount the retaining plate. (the one you slide over the spline, then rotate in the grove, and screw onto the sprocke with the 2 bolts.) - Does anyone's 14t have this recess, I'm sure Ducati did not produce a one off bike for matsoutback...

3. I have ridden it over 1200km with the 14t, and the feel of the grind is reducing. It must be said, the "grinding" only happen when slowing /  coasting, in nutral. The shop, whom have a great reputation BTW, say it is OK to ride.

4. It is obviously better riding it with the gearing this way, so I have purchased a 41 for the rear and will change it over to 15 /41 this weekend. I also guess I'll be bying a new chain too..

5. Why did you go to a 15/43?

[ungeheuer]

.... I ordered another 14t from Ducati (using their part number) for the 796, this sprocket did not come with the tapped screw holes to mount the retaining plate. (the one you slide over the spline, then rotate in the grove, and screw onto the sprocke with the 2 bolts.)

Sorry if this seems like a dumb question, but just to be clear, does your stock 15t sproket have the 2 bolts and retaining plate (items 12, 13, 14 shown below):



or is it like M1100 with one large retaining nut (items 29, 13,12 shown below):

[matsoutback]

Thanks for your diagram.

It matches the top one, with the retaining plate.

You can't see the recess I refer to on this diagram, because it is on the side the plate mounts to.

[ungeheuer]

Right.  So since M796 uses the locking plate (top pic) like M696 does, then I'd really want to be sure it was mounted correctly.  Despite what your dealer says, I wouldnt ride it until I was sure.

You can't see the recess I refer to on this diagram, because it is on the side the plate mounts to.

So the recess on the stock 15t sprocket allows the retaining plate (item 13) to sit within it, causing the stock sprocket to sit more outboard (as in closer to your left boot) than the unrecessed 14t item?  In other words without this recess your aftermarket 14t is running further in on the output shaft, closer to the motor?

Not wishing to overly alarm you (and the following is related to DSS M696 which uses locking plate for sprocket retention) but you'd wanna make sure you avoid something like this >>  

http://www.ducatimonsterforum.org/index.php?topic=43390.0

The 796 instance begins here  >>  

http://www.ducatimonsterforum.org/index.php?topic=43390.msg1056121#msg1056121

And given the 2mm difference in sprockets which you've described this seems to me to be relevent:

Looks like the wrong sprocket maybe.  Does the one on your bike have the shoulder sticking out toward the engine like the one in the diagram?

I am guessing someone tried going down a tooth in the front, and bought the wrong sprocket for an older monster.

mitt

5. Why did you go to a 15/43

Stock M1100 gearing is 15/39.  Like you I liked the lowered 14/39 gearing.... but then I wanted an AFAM quick change sprocket carrier.... which meant a new rear sprocket... so I took the opportunity to go to 15/42... (+3 on the rear is more or less = to -1 up front) along with a new chain....  Shortly after that... I opted to lower gearing just a little more to the 15/43 which I find perfect.  Wouldnt suit the autobahn bashers like Raux though...

[matsoutback]

You are correct in your description of where my chain runs.
I would suggest everyone who is running the 14t has altered the location of where the chain runs - closer to the bike.

I had read the linked posts - but thanks for bringing those up again. I am not sure if any technical solution came out of that, it is just quite worrying. Good that Ducati came to the party though.

I will be swapping back to the 15t this weekend first to check if the feeling I get disappears, then, if it does (pretty confident it will), I'll be using the 41t on the rear I have already bought.

I will report back with my findings after the weekend.

[ungeheuer]

I would suggest everyone who is running the 14t has altered the location of where the chain runs - closer to the bike.

Nope.  Dont agree.  No reason why a correctly specified, correctly fitted 14t sprocket should alter the chain run.

[Curmudgeon]

Nope.  Dont agree.  No reason why a correctly specified, correctly fitted 14t sprocket should alter the chain run.

[Raux]

I ran an aftermarket 14t bought from a Ducati dealer for most of the first 5000 miles or so. no issues. It was installed correctly.

[matsoutback]

So the consensus is - I have the wrong part on my bike.

Where do you lot recommend getting sprockets from?