Stelvio CARC failure in Oz AND South Africa

[bcls482]

Could you post the year and serial number of your bike.  I have a 2012 and I am wondering if Guzzi had a bad batch of swingarms because this problem seems very rare, but very worrying at the same time. 

[pauldaytona]

Could you post the year and serial number of your bike.  I have a 2012 and I am wondering if Guzzi had a bad batch of swingarms because this problem seems very rare, but very worrying at the same time.

 I'm trying to collect numbers, and have now 1.5 If someone knows how to contact the Australian owner to get me the VIN. I can lookup production date with that. Three bikes out of a few thousand is very litte to draw conclusions. Who has seen the production process in  the factory, knows that not all part come and get mounted in a first in first ouit way, it's in batches. If you have a VIn or enginenumber and another that is 10 higher, that doesn't tell you the low number is made earlier. If they are mode then 100 apart, then chances are good that the lower number is made earlier.

 Engines waiting to be tested in the blue test cabines.

[Vasco DG]

Well I can confirm they the holes are threaded, M8. Not sure of the clips are press in or themselves threaded, I pried one out. If I can I'll post a couple of pics later.

[jacksonracingcomau]

If the swing arm supports the wheel from one side, and it broke under the rider's and its own weight,  why is the tire tipped and turned the way it is?   Shouldn't  the gearbox side be down?  Wouldn't such an accident try to pull the unit apart?  The unit looks compressed. It sort of looks more like impact damage to me.  YMMV

You could represent the manufacturer in court, they need expert witnesses like you, in fact they're are a few on here who seem to have this expert opinion, hope none of you have it happen yourselves, be a horrible epitaph.

[jacksonracingcomau]

I'm trying to collect numbers, and have now 1.5 If someone knows how to contact the Australian owner to get me the VIN. I can lookup production date with that. Three bikes out of a few thousand is very litte to draw conclusions. Who has seen the production process in  the factory, knows that not all part come and get mounted in a first in first ouit way, it's in batches. If you have a VIn or enginenumber and another that is 10 higher, that doesn't tell you the low number is made earlier. If they are mode then 100 apart, then chances are good that the lower number is made earlier.

 Engines waiting to be tested in the blue test cabines.

There was link to auction site in other thread would've had VIN but no longer available
Doubt owner kept record of VIN but importer would certainly know, probably Pickles (auction house) too
I'm still puzzled why importer didn't test broken arm and / or shock etc, I would've for sure, selling as is let a whole lot more people know, not wise IMHO

Guess they're treating it like cam problem, case by case appraisal, if in warranty they'll pay
If out you need FSH, guess they'll actually pay in both cases but only if you push. If people pay for cams they're happier, why not swinging arms ?
Doubt they'd fight a claim in court, just down to whether anybody needs to do it, I'd expect dealers to deal with this, if factory don't pay they're next in line for a writ.

[Vasco DG]

Got the Vin# of the Oz bike, PM'd it to Paul to see if its close to the other known failures.

Pete

[MotoZA]

Or preload adjustment. If the preload is not set properly, and the shock is being bottomed out, that might add a lot of impact type stress. I found the spring on the stock 2009 pretty weak when loaded.

Rebound, as one of the forum members PM'd me, can also cause problems. If riding along on a bumpy road with corrugations and rebound damping is set too high compared to compression damping, the spring will pack (basically it doesn't get enough time to expand between loads from the corrugation). The the shock can then easily "bottom out" since the coils will be touching one another at that point, or they might be very close to one another so that effectively you have no more travel on the spring. All the load then goes through the wheel and swing-arm into the frame. Still, one would hope that the swing arm is stronger than the wheel, which clearly was not the case in my failure since the wheel and tyre is still in perfect condition.

I've been on rides where guys hit a washout in a gravel road and they bend rims, if that happens you should definitively inspect the suspension and ancillary parts.

[jacksonracingcomau]

Rebound, as one of the forum members PM'd me, can also cause problems. If riding along on a bumpy road with corrugations and rebound damping is set too high compared to compression damping, the spring will pack (basically it doesn't get enough time to expand between loads from the corrugation). The the shock can then easily "bottom out" since the coils will be touching one another at that point, or they might be very close to one another so that effectively you have no more travel on the spring. All the load then goes through the wheel and swing-arm into the frame. Still, one would hope that the swing arm is stronger than the wheel, which clearly was not the case in my failure since the wheel and tyre is still in perfect condition.

I've been on rides where guys hit a washout in a gravel road and they bend rims, if that happens you should definitively inspect the suspension and ancillary parts.

Nearly right, sorry, have to say it now
Shock will bottom out long before spring coil binds on anything halfway well designed
First you hit the rubbery bump stop, then that compresses till it can't (very high speed comp damping)
Then the load goes somewhere else
Might be problem, might not.

[MotoZA]

Just closing the loop...
Here's another, almost identical failure: http://wildguzzi.com/forum/index.php?topic=79597.0

[Vasco DG]

Yes, perhaps this thread should be merged. That way the poorly analysed target will be even easier for haters to aim at.

Alternatively, we can try and get some USEFUL data and evidence to make informed decisions and choices. Here? Fat chance I fear......

Pete

[brlawson]

With all this negative discussion around the Stelvio it might be good to inject some positive vibe.

50 plus paying homage to the creator.

https://www.youtube.com/watch?v=84taL6pT4og

[MotoZA]

My goal is not trying to make it easier for haters.

I accept that it may be bad luck on my part, but I'm not the only person in the world who can strike it bad, so I think it's fair that other riders of Stelvios should know about this.

If we had useful data, we wouldn't be having this conversation. Perhaps try to see this as an attempt to get some useful data, unfortunately I can't add anything more than what I wrote in my original post.

[Wayne Orwig]

Nearly right, sorry, have to say it now
Shock will bottom out long before spring coil binds on anything halfway well designed
First you hit the rubbery bump stop, then that compresses till it can't (very high speed comp damping)
Then the load goes somewhere else
Might be problem, might not.

Yes, the bump stop was destroyed on my original shock. Not saying anything about the overloaded rear seat.
I had the shock resprung and revalved. Now it never bottom out, and seldom reaches fully extended.

[Triple Jim]

Again, parts like this need to be designed for worst case loads times a safety factor like three.  Worst case could be a bottoming shock with a 250 lb driver and 300 lb passenger.  If it is, design for three times that load.

[WitchCityGuzzi]

With all this negative discussion around the Stelvio it might be good to inject some positive vibe.

50 plus paying homage to the creator.

https://www.youtube.com/watch?v=84taL6pT4og

[canuguzzi]

When you load 500 pounds on a 600 pound motorcycle, your problems started some time before that. Time to rethink what you're doing.

[sib]

When you load 500 pounds on a 600 pound motorcycle, your problems started some time before that. Time to rethink what you're doing.

From my observations, that's more the norm than the exception, at least among the patrons of the motorcycle bars in my area.

[Triple Jim]

Yes, you design not for sensible customers, but for worst case customers.  Back in the '80s I was given the task of designing some quick-erect military vehicle decoys.  The design had been narrowed down to use standard frames that were available like the ones you see at trade shows that start out as a bundle of aluminum sticks, and when you give a pull, they quickly make a wall suitable for hanging display posters and things like that.  My question was then whether or not they'd hold up to life in the military.

I recruited a coworker, and we took two of these frames, one from each of two manufacturers, to a park and dragged them around in the dirt, pulling on single aluminum tubes, dropping large rocks on them, and doing anything we could think of to damage them.  We learned that one was less susceptible to damage than the other, but the damage it did sustain was not field repairable.  The other one suffered more damage, but the aluminum tubes mainly popped out of their end fittings and could be replaced by hand.  The test taught us a lot.

The point is that the design was based on what could happen from abuse, not what happened when treated with respect by nice, careful people.

[rss29]

When you load 500 pounds on a 600 pound motorcycle, your problems started some time before that. Time to rethink what you're doing.

I agree, but I'll bet that's still well within the bike's GVWR. I regularly load 300+ pounds of rider and passenger on my 400 pound bike and it handles it with ease. The Stelvio is marketed as an adventure bike, ready to take you and all your gear to the far corners of the globe. All components on the bike should be up to the task. This certainly isn't cause for panic, but the failures we've seen are pretty dramatic. If I had a Stelvio I'd definitely be out in the garage right now with a flashlight inspecting the swingarm for cracks, assuming there even is a crack that shows up before failure.

[tazio]

When you load 500 pounds on a 600 pound motorcycle, your problems started some time before that. Time to rethink what you're doing.

Ratio seems reasonable to me.
Might be because I ride a mountain bike..

[Chuck in Indiana]

Yes, the bump stop was destroyed on my original shock. Not saying anything about the overloaded rear seat.
I had the shock resprung and revalved. Now it never bottom out, and seldom reaches fully extended.

Uh oh.. She's a redhead, too..

[Vasco DG]

My goal is not trying to make it easier for haters.

I understand that. My feeling is that since all three failures we know about have been on machines from what seems to be a very small window of manufacture there was probably a bad batch of castings. This is particularly worrying because nobody knows how many might be flawed.

I'll be writing to our tech and warranty wallahs later today and trying to see if we can shake some action. If we can get some input from the factory on what Vin's might be affected they can be summoned in for, at the very least, an inspection. The last thing I want is people, particularly my customers, being injured or killed.

Pete

[lucky phil]

Well after reading the details of both arm failures and seeing the pictures I would be drilling out the cable mount hole to the thread root depth and would then do a dye pen check (kit price around $30au) All being well I would then cold work the hole and use a rubber well nut to hold the cable clip.
Looks fairly clear to me the cable clip hole is most likely source of the crack propogation but even if its not the above wouldnt hurt.
Ciao

[canuguzzi]

I understand that. My feeling is that since all three failures we know about have been on machines from what seems to be a very small window of manufacture there was probably a bad batch of castings. This is particularly worrying because nobody knows how many might be flawed.

I'll be writing to our tech and warranty wallahs later today and trying to see if we can shake some action. If we can get some input from the factory on what Vin's might be affected they can be summoned in for, at the very least, an inspection. The last thing I want is people, particularly my customers, being injured or killed.

Pete

That is a very considerate and noble thing to do.

[Vasco DG]

That is a very considerate and noble thing to do.

No, it's the right thing to do and it's also arse-covering. If I think there might be a problem and I've alerted the 'Powers That Be' nobody can complain I didn't pass on information. Arse Covered! An email trail is a useful thing.

[jacksonracingcomau]

Yes, the bump stop was destroyed on my original shock. Not saying anything about the overloaded rear seat.
I had the shock resprung and revalved. Now it never bottom out, and seldom reaches fully extended.

And this is exactly what I'd be looking at if I was inspecting the bikes
Symptom & cause
Repeated bottoming hard could be taking swingingarm where it was never meant to go, finally to heaven, repeat, could be

OP (Bill?)
Is your bump stop intact ?

Pete
Do you know where the Pickles bike went ?

Wayne
 why your shock doesn't fully extend leaving bumps is another issue,  , go pro film of shock working hard would tell you.
If your back wheel leaves the ground without shock extending, next hit will be big & probably harsh, hitting sleeping policeman fast good test.
Hope that translates into Merkan, is colloquial for "speed bump"

[JeffOlson]

I wonder if Ewen McGregor is taking an extra swing arm with him on his next adventure...

[Vasco DG]

No idea where it went. I called pickles and they were less than helpful. I was going to bid on it but it went stupid.

Pete

[canuguzzi]

Can anyone with a Stelvio post the allowable gross weight of the bike? Should be on a sticker somewhere.

[MotoZA]

OP (Bill?)
Is your bump stop intact ?

Yes, as far as I could see. Would even slight damage be visible?