Stelvio CARC failure in Oz AND South Africa

[jacksonracingcomau]

Yep, very well done
But
I know you have enough on your plate working out cam & big end problems, Pete
How about someone with the technical ability / equipment get the broken arm and analyse for the WHY
Loads of expert opinions on here from pictures, I'm sure conclusive could be ascertained from real thing, odd that neither importer wanted to do this or send it home to Italy.

Pete's got the bike working again, anyone here who can do the analysis ?

[Vasco DG]

If the owner sends me the broken shit I can take it to the Australian Mint and ask their opinion.

I still believe it must of been a batch of bad castings, similar sort of problem to the shock linkage issue. Thing is there are tens of thousands of these things out there and then there was a few failures from the same manufacturing period after which it was all good again. Design flaw doesn't add up. Manufacturing flaw does. It doesn't make any difference, Piaggio is still denying responsibility. I have my arse covered, I wrote to our importer expressing my concerns. No reply was forthcoming unfortunately...... ...

Pete

[MotoZA]

Just to update this in case people thought it was bullshit. Swingarm and torque rod got on the 'Big White Bird' this AM, Should be in the steaming fleshpots of Kyalami in seven to ten days.

 

Thanks!

[Vasco DG]

There is no need for this bowing shit! What else was I going to do with it? Skip it in ten years time! Fer fucks sakes!

[canuguzzi]

From a purely safety standpoint, is there something Stelvio owners should look for in a specific area or is this just something not to worry about because if it happens, it develops so quickly that cusory inspection is worthless?

[Vasco DG]

Very hard to say but given the nature of cast aluminium my guess would be that once started failure would be very rapid, maybe within only a handful of stress cycles but I don't know for certain.

Obviously it would pay to check regularly, especially if you own a machine manufactured mid 2012 but whether there would be anything to see is a different matter.

Pete

[RANDM]

Hi people,
I'm new around here - trying to learn before joining the Family so to speak.
Forgive me if this suggestion is dumb but why not be proactive and just Tig
the threaded hole if that's the weak spot and Araldite a clip into place to hold
the Brake Line?

Cheers Maurie.

[lucky phil]

Hi people,
I'm new around here - trying to learn before joining the Family so to speak.
Forgive me if this suggestion is dumb but why not be proactive and just Tig
the threaded hole if that's the weak spot and Araldite a clip into place to hold
the Brake Line?

Cheers Maurie.

Well you could, but getting a competent welder that knows what material to use and is ok to weld cast might be the issue. Just adding another variable.
I'd still go with the open the hole to the thread root dia, dye pen test, cold work and use a rubber well nut.

Ciao

[rboe]

I wonder if there is anyway to look at the casting to figure out what batch it came from. See if an owner can inspect their arm for a smoking gun.

[Bonafide Bob]

 My riding Bud and I are removing my CARC tomorrow to service the swing arm bearings and will do a visual inspection of the CARC while it is off.  We did his Stelvio a few weeks ago and the CARC looked fine, the bearing were in need of grease, it seems a lot of these bikes leave the factory with minimal grease in the bearings.
 Bob

[HDGoose]

I am planning on buying another bike next year. Because I am 'Goose', I Guzzi's will get a hard long look first. But what ever bike I buy, I will buy the software and hardware to maintain these newer bikes. And if I get the house I am looking at, I'll even have my own large 2 bay garage! So I can also then buy my Ambo/Eldo...

[RANDM]

Well you could, but getting a competent welder that knows what material to use and is ok to weld cast might be the issue. Just adding another variable.
I'd still go with the open the hole to the thread root dia, dye pen test, cold work and use a rubber well nut.

Ciao

Point ……… what about filling with quick metal and
reinforcing in and out with carbon fibre?

Maurie.

[Chuck in Indiana]

Point ��� what about filling with quick metal and
reinforcing in and out with carbon fibre?

Maurie.

I'm with Phil. I feel the thread is the stress riser. Maybe.  At any rate, doing that wouldn't get rid of the thread.

[Wayne Orwig]

  it seems a lot of these bikes leave the factory with minimal grease in the bearings.

My theory is that some bonehead at a bearing manufacturer specs a very tiny layer of grease for bearings, assuming they are well sealed, and assuming they are used at higher speeds. Any more grease would just get hot and leak out.
But they don't realize that in this application, the swingarm pivot bearings only have a slight amount of motion, and the seals are lacking. So they really need a heavy dose of grease to protect them from rust.
But that connection is never made, and the bearing manufacturer doesn't even see the issue. Well, he does see additional bearings sold to repair the rusted out, under greased, bearings.

[Bonafide Bob]

My theory is that some bonehead at a bearing manufacturer specs a very tiny layer of grease for bearings, assuming they are well sealed, and assuming they are used at higher speeds. Any more grease would just get hot and leak out.
But they don't realize that in this application, the swingarm pivot bearings only have a slight amount of motion, and the seals are lacking. So they really need a heavy dose of grease to protect them from rust.
But that connection is never made, and the bearing manufacturer doesn't even see the issue. Well, he does see additional bearings sold to repair the rusted out, under greased, bearings.

 I bet the steering head bearings need more grease too.
  Bob

[canuguzzi]

My theory is that some bonehead at a bearing manufacturer specs a very tiny layer of grease for bearings, assuming they are well sealed, and assuming they are used at higher speeds. Any more grease would just get hot and leak out.
But they don't realize that in this application, the swingarm pivot bearings only have a slight amount of motion, and the seals are lacking. So they really need a heavy dose of grease to protect them from rust.
But that connection is never made, and the bearing manufacturer doesn't even see the issue. Well, he does see additional bearings sold to repair the rusted out, under greased, bearings.

If true, the bonehead would be the moron at Moto Guzzi, not the bearing maker. Moto Guzzi is supposed to spec the right bearing and know the application. That is what application engineers are for. The bearing maker isn't making the motorcycle nor the swingarm.

Blame where blame is due, the company making the motorcycle. If the suppliers have problems, that too is on MG. They are supposed to do QA and the buck stops with them.

Bearing maker probably sells a lot of bearings and selling a few more to MG because the application spec is crappy doesn't mean much to them, a few more bearings to MG doesn't mean anything to them.

[Cool Runnings]

Kinda glad I got a Norge.

[Wayne Orwig]

Kinda glad I got a Norge.

Right, since it doesn't have the CARC crap.

[John Warner]

I bet the steering head bearings need more grease too.
  Bob

The Headstock Bearings are better protected from the Elements (at least they are on the Stelvio), and they don't do quite so much 'work' either, rotation-wise, so the Grease issue isn't so critical.

Always best to check/clean/re-lube as required though. 

[Bonafide Bob]

I greased the swing arm and shock pivot bearings on my 2013 Stelvio today, all the bearings were in need of grease. My riding Bud...Jay came over to help it, it took about two hours to do the service. It seems these bikes leave the factory with very little grease in these bearings and I bet other bearing on the bike need attention too.  FYI.... I bought the bike new this year it has under 12,000 miles in it.
 I inspected the CARC and didn't see any hair line fractures.

 Bob

[MotoZA]

You won't see the fracture (if there is one), it's like trying to spot a crack in a weld. One way to see a potential crack would be to dye-pen the area close to the threaded hole, and you'll have to do it on the inside to be safe since the paint will most likely cover up the crack.

[motrhead]

The Headstock Bearings are better protected from the Elements (at least they are on the Stelvio), and they don't do quite so much 'work' either, rotation-wise, so the Grease issue isn't so critical.

Always best to check/clean/re-lube as required though. 

 In my current career as a millwright, I have found that bearings that don't spin (in other words bearings that operate through less than 360 degree rotation) fail early. I have my own theories as to why this is, but I see it often. Yes, this is an oversimplification, but this is my empirical observation. I grease these more often than bearings that rotate. Swingarm bearings and headstock bearings kind of match that description for me.

[Triple Jim]

In my current career as a millwright, I have found that bearings that don't spin (in other words bearings that operate through less than 360 degree rotation) fail early. I have my own theories as to why this is, but I see it often.

You're certainly correct.  Bicycle and motorcycle head bearings not only don't rotate a full 360 degrees, but they spend most of their time at or near the center of travel.  The races get dents worn in them and things go downhill from there.  Any repetitive non-fully-rotating application is likely to cause non-uniform race wear.  At least Guzzi swing arms use roller bearings, which aren't quite as bad as ball bearings in this kind of application.

[RANDM]

In my current career as a millwright, I have found that bearings that don't spin (in other words bearings that operate through less than 360 degree rotation) fail early.

I found that with my R1150R Paralever Bearings, replaced the $60ea. OEM's with Nylatron Bushings care of an ADV. inmate - I'm one of the riders testing them.
 
The TRB's were badly Brinelled, they have little movement and end up wearing grooves across the race that the rollers just sit in.

Cheers Maurie.

[canuguzzi]

I found that with my R1150R Paralever Bearings, replaced the $60ea. OEM's with Nylatron Bushings care of an ADV. inmate - I'm one of the riders testing them.
 
The TRB's were badly Brinelled, they have little movement and end up wearing grooves across the race that the rollers just sit in.

Cheers Maurie.

I was going to ask, would not synthetic plain bearing types work better for those applications?

Seems someone thinks so, test results will be interesting. The nylatron is in the class is self lubing plastics yes? Self cleaning too if I remember correctly and this is the same material I was thinking if. Even when gritty they continue to function well.

[Vasco DG]

F*ck this shit! Has the new swingarm arrived yet?

Should be there before Christmas!

Pete

[MotoZA]

F*ck this shit! Has the new swingarm arrived yet?

Should be there before Christmas!

Pete

It has, on Tuesday. Sent you a PM about it (?), will reply via email to.

Thanks.

[Vasco DG]

Nah, that's OK. Must of been a cock-up with the PM. As long as it's there? All good! Keep us posted.

 

Pete

[MotoZA]

I've got a dodgy internet connection at work, plus they're busy upgrading us to fibre so the connection is up and down the past week.

Waiting for a quote from the local dealer to fix the bike, then have to decide if I'm going to sell or keep her. Lately I've been leaning towards keeping her.

Do you have an idea how many Stelvio's (specifically) have been sold since circa 2012, can one perhaps estimate looking at the last/latest VIN numbers of ones sold?

[RANDM]

I was going to ask, would not synthetic plain bearing types work better for those applications?

Seems someone thinks so, test results will be interesting. The nylatron is in the class is self lubing plastics yes? Self cleaning too if I remember correctly and this is the same material I was thinking if. Even when gritty they continue to function well.

It's a Molybdenum infused type of Nylon so yes self lubing. ADVrider decided to try it as it's used for
Suspension Bushes in NASCAR. There are around 20 or so of us testing them - so far boringly simple
and totally reliable with no reported problems and I guess maybe 15,000 miles on the longest travelled
tester so far.
We did have one guy "take one for the team" have an accident and actually deform (but not break or crack) them - but his back wheel/FD got run over by a 5 ton truck towing a trailer with a medium sized
Bobcat on board and dragged 15/20 yds down the road.

Maurie.