Serious Safety Issue on a 2009 Monster 696

[mikesmithmjs]

no jb weld for me. i wouldn't feel comfortable using an aluminum swingarm that is no longer up to initial specs. too brittle of a metal?

[WetDuc]

Yea, it would be it would be totally gangsta.

[greenmonster]

I'm betting this is human error of some sort--either in assembly(?), from the prior owner or from the shop.

+1.

It looks more like it has vibrated a short period of time, wear marks looks like retainer has beated against axle.

Changed 2 on mine due to slow wear during 130 000 km`s, they didn`t look like that, much smoother wear.

[floyd turbo]

It would take some serious work to install that retainer plate wrong.

bfh?

[ScottRNelson]

I saw this same thing on my ST2, but no swingarm damage from that.  The first time I had a retainer plate break.  I overtightened one of the two screws and after a few thousand miles the one screw broke, then the plate flexed and snapped at the other end.  That one ate an aluminum sprocket in just a few hundred miles, but didn't damage anything else.

I've posted the photo of the damaged sprocket before: http://i25.photobucket.com/albums/c67/scottrnelson/Ducati/Sprockets.jpg

I replaced the retainer plate with a gold colored one and within about 1000 miles it did just what I see in the photos in the original post.  It apparently pounded against the splines until it wore new grooves in it, then slid to the inside in exactly the same way.  It's probably sitting around somewhere in my garage still.  Fortunately I had started checking for stuff like that whenever I lubricated the chain, so I caught it before any damage was done.  I made sure to get one of the harder black retaining plates the next time and didn't have any more problems with it.

You'll also get less vibration if you lubricate the splines with grease once in a while.

The sliding retaining plates are something that happen once in a while to Ducatis.  You have to check for it whenever you lubricate the chain, which should be every 300-500 miles.

[mikesmithmjs]

Hi Scott,

Thanks for the similar situation.  However, I cant seem to find in the owners manual where it says to check the sprocket plate ever time you lube the chain. Otherwise i would have checked it.  Is there a secret manual like the secret menu at in and out burger that as a ducati owner one should know about to prevent getting seriously messed up?

Even though these plates have been used for some time, that doesn't mean it is the optimal mechanism.

I don't mean to come across wrongly, but I am so upset at this situation and don't know how to go forward.

It used to look like this

[Buckethead]

Is there a secret manual like the secret menu at in and out burger that as a ducati owner one should know about to prevent getting seriously messed up?

It's called the DMF. Welcome. 

Sorry we couldn't help you sooner. 

[mitt]

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

[ducpainter]

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

Thanks mitt...

+1

[mitt]

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

[koko64]

I hope the factory comes through for you.

My old 900 has the same set up as others have mentioned. My retaining plate chewed out at 20,000 miles. It was the original (15 years old) one and I noticed it due to a change in how my chain was positioned. It created premature wear on the rear sprocket by altering the chain alignment, but no other damage. This occurred in a short time as I clean, lube and check my chain regularly. I inspect the chain weekly. I use a straight edge and measure axel alignment, etc also. I don't rely on the indicators on the swing arm 'plates'.

My local dealer told me that it was common enough for them to keep a few retainer plates in stock. I did notice that the original plate was thinner than the replacement one which was a more substantial item.

Come to think of it the same thing happened on my '92 Superlight. I replaced the plate and all was well with no damage. I don't understand how it happens because it looks an ok system when you replace the plate and see how it works. Yet it does fail but I haven't worked out how. Possibly severe chain/sprocket misalignment would do it, but it would have to be way out you'd think.

[ScottRNelson]

Thanks for the similar situation.  However, I cant seem to find in the owners manual where it says to check the sprocket plate ever time you lube the chain. Otherwise i would have checked it.  Is there a secret manual like the secret menu at in and out burger that as a ducati owner one should know about to prevent getting seriously messed up?

If you follow the Tech forum for a long enough time, all of this stuff eventually comes up.  I posted about the broken retainer plate when it happened, and I posted something else when I had the other one wear through.  If there were someone dedicated enough, they would gather all of the good information like that into one place.  But that requires someone who understands the difference between the quality posts and the trash that shows up on any large forum.

I've been studying Ducatis and Monsters since I got my first one in 1997.  After a couple of years of following several different forums, I had learned most of what I needed to know, although I still didn't believe that I needed a steering damper on a 1997 M900 until I needed it and didn't have it, crashing and totaling the bike.

Anyway, I still have an interest in Ducatis even though I no longer own one.  I'm trying to learn all of the secrets about the big KTMs now.

[koko64]

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

Nothing quite like human error. .

[brad black]

i've seen about 1/2 a dozen do this in 16 years.  mainly smaller engined bikes from memory - never seen a 996 do it for instance.  probably all dual sided swingarms too, which may be a point about alignment.

there was a recall on the early st2 for this, altho none of the ones we did had any problem.  i replaced one of those plates with a chain and sprocket change (900ss) yesterday that was half worn thru, usually they're reusable with only minor marking.

possibly a chain alignment issue, get a laser aligner to make sure it's straight.  apart from that (and without good photos of the swingarm) i'd fit a new plate and go.  and go to the dealer and demand a new swingarm, just for the hell of it.  it's not a serious safety issue, and if you're looking at the chain you should see aluminum shavings fairly quickly.

there's a few reasons they put that "before you ride" stuff in manuals.

1/ for owners to ignore it.
2/ to point out your failings when it goes pear shaped
3/ to protect their arses.

[WetDuc]

There's no secret manual, but there is the workshop/service manual.  That's full of good stuff.  The user manual that is free to download and comes with the bike is pretty basic and quite useless.
You can get the workshop manual as download or CD for a few bucks on google searches or ebay.