Serious Safety Issue on a 2009 Monster 696

[DucatiSTi]

On the upside, I don't think the swingarm looks that bad from the pictures.  If just a 1/8" of material was removed, I would call it a weight reduction/mod and keep on riding it after getting a new sprocket and plate for about $100.

And, in ranking of mechanical failures that could have lead to crashes, I had a rental 620 monster that the rear axle feel out of the swingarm while I was riding because the rental owner didn't torque the axle nuts properly.   I don't blame the bike or design though.


mitt

I agree

Based on the pics, I would say that the swing arm is perfectly fine

Dumor/polish the damaged area or drop a puddle of weld in the damaged area and clean it up

Then get it repainted

This is a good story of why I do my own bike service - I just don't trust many techs out there

[Speeddog]

It could have worn through the teeth on the plate, but I've not seen one wear through, and definitely not at such a low mileage.

Perhaps the plate or sprocket were manufactured incorrectly.
This retention system depends on proper alignment of the bolt holes and the spline teeth at manufacture.

[mikesmithmjs]

I don't have any current photos of the rear.

In terms of alignment, i have used the built in gauges on both sides of the swing arm to check before each ride.  Both sides have been equal since I bought it 18 months ago.  Are they a good indicator for alignment, or are they just for show?

[ducpainter]

I don't have any current photos of the rear.

In terms of alignment, i have used the built in gauges on both sides of the swing arm to check before each ride.  Both sides have been equal since I bought it 18 months ago.  Are they a good indicator for alignment, or are they just for show?

The marks are not the best way to align your wheel. 

You can use a laser, or an old fashioned tape measure.

[battlecry]

"Are they a good indicator for alignment, or are they just for show?"

Wouldn't call them "for show", rather an "uncalibrated instrument". 

Follow Nate's advice and use a simple tape measure from the swingarm pivot to the axle.  No need to locate the centers by eye, measure to the edges of the holes and average the measurements to calculate the location of the centers.  See how close you are and whether you can use the markings to give you a meaningful alignment reference.  On my bike with the older style DSS I found too much play in the plates so I do not use the markings.

   

[mikesmithmjs]

Is the DID chain I see in the picture stock?  Is there any indication the rear sprocket has been changed or worked on?

I bought it used with 182 miles on it from the local Ducati dealer.  I haven't changed anything since I bought.  The local dealer did 600 mile service last year.

[WetDuc]

Just sayin, the rear wheel adjusters on the 696 are FAR BETTER than the ones used on the previous DSS monsters.  They are a completely different design.

[Raux]

I bought it used with 182 miles on it from the local Ducati dealer.  I haven't changed anything since I bought.  The local dealer did 600 mile service last year.

Mike, I think we are all under the same assumption... someone did something to this bike before you got it, it somehow wasn't aligned/installed right.

[mikesmithmjs]

I understand that assumption, nonetheless i would like to know if there is a better way to attach the sprocket in a more error proof way?

[mitt]

I understand that assumption, nonetheless i would like to know if there is a better way to attach the sprocket in a more error proof way?

Of course there are better ways.  For example I imagine MotoGP bikes do not use this setup.  For another example, look up the parts diagram for the bigger Ducati bikes - they use a nut and the output shaft splines are threaded. 

The real question is - is this plate design good enough for an entry level Ducati Monster - and I think the overwhelming answer is yes - if everything else is correct also and the parts are to spec and they are installed correctly.  You are the only one I have seen documented to have such and early problem with it.

Can you realistically change the design on your bike - probably not without considerable expense.

mitt

[Porsche Monkey]

I understand that assumption, nonetheless i would like to know if there is a better way to attach the sprocket in a more error proof way?

http://www.millerwelds.com/products/mig/

[mikesmithmjs]

http://www.millerwelds.com/products/mig/

Nice!

[Ddan]

Of course there are better ways.  For example I imagine MotoGP bikes do not use this setup.  For another example, look up the parts diagram for the bigger Ducati bikes - they use a nut and the output shaft splines are threaded. 

The real question is - is this plate design good enough for an entry level Ducati Monster - and I think the overwhelming answer is yes - if everything else is correct also and the parts are to spec and they are installed correctly.  You are the only one I have seen documented to have such and early problem with it.

Can you realistically change the design on your bike - probably not without considerable expense.

mitt

This design was acceptable for way more than entry level, small displacement bikes for years.  Nothing is idiot proof but your problem is not a design problem or flaw.  Something is screwed up and the retainer plate is a symptom.  Be thankful that the problem has shown up there and not in a broken chain, which will often means broken cases.

[junior varsity]

I hate to pile on, but this should have been caught by routine inspection way before it got this bad.  Believe it or not, motorcycles used to be unreliable pieces of machinery, and before each ride, you did a walk around and looked at things like the chain and where it was touching.

The original owner screwed up this plate somehow, and traded it in before the damage was realized.

mitt

+1. Before every ride. Its not just checking tire pressure, but its looking at the parts of the bike that shouldn't wear, etc. Its incredibly important. I make the wife do it too so she is more familiar with the motorcycle.


and +1 to the design being acceptable for a variety of motorcycles. The other choice from Ducati is a giant freakin nut and a chisel-bent plate below it.

[ducpainter]

My 996 uses the same retainer plate design.

No issues in 10 years of racing and track riding.

The design isn't the issue.