Broken Swingarm

[corsaro chris]

Steve;

The German forum includes quite a bit of chatter about investigating a batch run of replacements. I'd like a little more information before I signed up for a replacement; most fabrications include welding these days; look at some BMW, Ducati etc., but we haven't heard of any problems there as we're very focused on our own sort!

I'd also welcome input from an engineer - I've read through the German site (thanks to Google translate) and will send a sample of information out to those interested...

As you say, this is going to run and run, and quiet rightly so as eight failures is a few (8?) too many!

As to numbers (as queried by Norbert), the GP was introduced in late 2007, and probably became the best selling bike in the range from 2008. Coupled with the Scrambler and to a lesser degree the Sport they probably sell more than the Corsaro - probably more than 1,000 a year across all three models (which have the same swing arm components), and maybe another 1,000 or so since 2011; but not many in India, I'd guess!!!

So close to 5,000 sales might be creditable, although only 800 in Germany (16% of those sold) might indicate that the total numbers are lower than Morini are claiming? Certainly in the UK the Corsaro is the most common model sold from 2007 through to 2009. Maybe it's 5,000 modern Morinis that have been sold and they're just confused...

Good riding,

CC

[miguel]

Due to the size of the company I would assume that the swing arms are sourced in batches and therefore if the swing arms have failed over a range of close VIN numbers it would indicate a manufacturing error.

If the failures have occurred over more than one batch and appear to be all model years then it would indicate a design issue.

From reading the original post it suggests that checking the welds indicates that it is more likely a manufacturing issue than a design (different manufacturing methods appear to have been used). Isolating it down to a manufacturing issue means that you could simply fit a different swing arm from another model year bike rather than going down the custom route.

Steve,

Since you have already struck up the conversation with the factory, would you be able to ask them the range of VIN numbers they believe could be effected? We may find its 2008MY, 2009MY, all post 2013, etc...

Miguel

[corsaro chris]

Hi Miguel;

Not what you want to be reading having just purchased a GP!

For what it's worth, one of the early pictures on the German forum is of a 2007 model year GP (i.e. - first production year), and the first reported failure may be from an early Scrambler.

As you suggest (and we are all secretly hoping) it could be that the fault is a rogue batch of swing arms which have failed in service, and that there are no more out there... It is worth reading the German site thread in detail, and a report will be published in their magazine, La Strega in due course. The ATG editor will have a copy of this, after which we can perhaps have a precis of once published...

Good riding,

CC

[günni]

schwinge_komplett_1.jpg (135.6 KiB) Viewed 31080 times

Steve,

Since you have already struck up the conversation with the factory, would you be able to ask them the range of VIN numbers they believe could be effected? We may find its 2008MY, 2009MY, all post 2013, etc...

no chance! i had the broken swingarm of the german scrambler in my hands. there is no production code on the swingarm, no production year, nothing!
no chance to identify a defective series.
the reaction of moto morini is a bad joke. we talk about broken swingarms, a safety-related component. each broken swing arm is one too much!

[MickeyMoto]

The more I see the more I think it is stress related.

I think the failure is 1/600 at the moment. Would you fly in an aircraft with a 1/600 chance of a stress fracture in a component? This assumes there were 5,000 models with that swinging arm made!

Surprised TuV not taken an interest....

[Painter]

Hi Chris
I have just contacted the factory again, with an updated appraisal of the current situation and concerns on this and other forums.
I have asked them to clarify the nature of the failures that they have identified, were they poor fabrication or stress related, don't hold your breath but at least we can ask!
I pointed out the negative impact on potential sales as the forum is an important point of reference for many potential buyers.
Perhaps this business will never be conclusively investigated to the point that we all can ride in the knowledge that out bikes are safe, the factory, as other members have pointed out will not admit any issues until it knocks on their door.
For my part I think constant vigilance, persistent emails to the factory from everyone on all the forums and then they might get fed up and have to accept or prove there is no issue.

Cheers Steve

[miguel]

schwinge_komplett_1.jpg

Steve,

Since you have already struck up the conversation with the factory, would you be able to ask them the range of VIN numbers they believe could be effected? We may find its 2008MY, 2009MY, all post 2013, etc...

no chance! i had the broken swingarm of the german scrambler in my hands. there is no production code on the swingarm, no production year, nothing!
no chance to identify a defective series.
the reaction of moto morini is a bad joke. we talk about broken swingarms, a safety-related component. each broken swing arm is one too much!

Hi Gunni,

In order to identify a range of faulty of effected vehicles you do not need the part to be date stamped. It is the VIN number on the chassis that will give us a range of failures for a given vehicle.

It is how all manufacturers work out which vehicles to recall and which ones to leave.

Chris,

I have tried joining the forum Granpasso.EU but my login details have still not been accepted so I cannot read it.

I am not too worried as if the bikes have been around since 2007 and sold in numbers in excess of 5000 then the failure rate is very low however, I believe that the company needs to conduct further investigation into the cause. It wont stop me form riding my bike but I think I will do as Steve says and send an email with some questions to MM.

[günni]

I am not too worried as if the bikes have been around since 2007 and sold in numbers in excess of 5000 then the failure rate is very low however,

sorry, the number is not correct! in the last 11 years, less than 5000 morinis were built and so this number includes corsaro, 9 1/2 and 11 1/2 too.
in germany, one of morinis main markets, we had round about 800 registrations in the last 11 years.
404 of them were corsaro, 132 granpassos and the rest are 9 1/2, scrambler and 1200 sport.

2006 = i could not find
2007 = 114
2008 = 145
2009 = 242
2010 = 108
2011 = 38
2012 = 16
2013 = 21
2014 = 2
2015 = 2

i think morini is not able to identify affected vehicles. my 2013 scrambler was produced with parts from 2007-2009. if they would do a good job, they would call back all.
in the moment tüv and kba has not been informed to protect the registration of our bikes.

[corsaro chris]

Thanks Gunni;

That's really useful information - I had suspected that about 5,000 was the total number of bikes produced, and that 50% of these would be Corsaro of one type or another... Perhaps we all need to sell our GP / Scrambler / Sport and ride Corsaro

However, I will stick with the GP for now (I can always wheel the Corsaro out when I need to have solo fun...) and we in the UK will all pester the Factory with e-mails etc., of concern and worry. I've also just booked a place to the German Teffen in June, so we might see a couple of GP riders there (and maybe some from Italy?)

Good riding, I think that 'winter is coming' to the UK...

CC

[Painter]

Hi Chris

Yes I share your concerns, but what can we do, sell our bikes refabricate or do as you keep riding and enjoy.

I will send once a week an email to the factory, perhaps others might want to do the same.

Went out the other evening, after I have fitted a modified BMW adventure screen, yes winter is here.

All the best

Steve

[Jay]

I just checked mine ( 2013 GP) - the welds I can see are quite chunky, regular, and convex, but it's dark and the bike is dirty. I'll clean it next weekend and post pictures.

Jeremy

[Red S]

Had a look at mine as well. The welds look fine, but there are some rather nasty gouges on the drive side near the pivot when a chain went. Some look to be maybe 2mm deep, which is worrying.

[RHThomas]

Here’s a thing:

I was down at Moto Corsa earlier having my MV serviced and talking to Ed who works there (and is always very helpful) I asked if they’d supplied any Morinis this year, he told me about a GP they supplied which the new owner took straight off on a trip and crashed it, riding quite hard by the sound of it though some S bends with a poor looking road surface. The swinging arm broke at the same place as in the pictures above, Ed showed me pictures of the road and the breakage.

As the bike was new, it went back to the factory for investigation and Moto Corsa received an email in due course stating that chain slack on these bikes be doubled from 25mm to 50mm. Leading one to conclude that a tight chain was thought to contribute to the problem.

I guess if the suspension was fully compressed of fully extended then the torque of the engine could put a lot of force on one side of the swinging arm through a tight chain…

I don’t know if the GP owners manual specified the change slack as 25mm, if it does then the word needs to be spread to increase to 50mm. Maybe a GP owner could confirm with the factory?

I think I shall be running the chain on my Sport on the slack side from now on.

Cheers,
Robin

[corsaro chris]

Robin;

Thanks for this; I'd noticed that the service manual for the 'As New' Granpasso I bought from the Factory last year had a increased movement range for the chain, and I'd chatted about this with Moto Corsas' mechanic (as you say, good people). I'd put the information in to issue 340 of ATG, and after to-days ride back from meeting Les, Jane and others at Buckfastleigh (including Ian, the chap we'd bought a house from in the early 1990's!) the bike has now done over 5,000 miles in the UK...

Prompted by your comments, I checked the revisions on the supplemental details on the data stick for the Gran Passo (there is no longer a printed manual...) and this is what I found (obviously copyright Moto Morini S.r.l.). Note that this is for the Gran Passo - I'd presume that the 9.5/11.5, Corsaro/Avio remain unchanged, although the Sport and Scrambler probably have similar modifications;

PAGE 75
Checking the chain tension every km 700
REPLACE BY
Checking the chain tension every km 500
PAGE 75
When the chain tension is correct a maximum travel of 20-25 mm is allowed.
REPLACE BY
When the chain tension is correct a maximum travel of 40-45 mm is allowed.

Useful information, I hope?

Good riding,

CC

[miguel]

Hi guys,

Chain tension for the GP is below: