Broken Swingarm

Anything to do with the 1200 GranPasso series
Maurizio_Granpasso
Posts: 5
Joined: 08 Aug 2012 12:26
Location: Italy

Broken Swingarm

Post by Maurizio_Granpasso »

Hello, I'm Maurizio from the italian GRANPASSO.EU forum.
In important that you check your swingarm (Granpasso, Scrambler, 1200 Sport) and look for fractures, because it could break near the ohlins shock.
The university of Stuttgart, Germany, found that the broken part is poorly developed and manufactured.
Here you can follow the discussion.
http://www.granpasso.eu/forum/viewtopic.php?f=4&t=3057
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Maurizio_Granpasso
Posts: 5
Joined: 08 Aug 2012 12:26
Location: Italy

Re: Bronken Swingarm

Post by Maurizio_Granpasso »

One of our best Morini mechanic in Italy told us that he don't believe that the problem was a poor develop (as written in the university report), but instead he stress that the problem was a bad welding.

If you look at your welding at it has a concave form, you may experience the fracture of the swingarm.
A concave welding means that the two part of the swingarm were too far during the welding process.

The welding must be convex.
Check also for fracture of the welding.
MonstroMorini
Posts: 81
Joined: 20 Feb 2011 15:48
Location: Wormer, Netherlands

Re: Bronken Swingarm

Post by MonstroMorini »

For those that dare/want to read the report, it is available here (german):
http://ital-web.de/forum/viewtopic.php?p=56296#56296, Siggi's post of 01-01-2016. The report took more than a year and you can not take the words of german engineers/scientists lightly, how much (as a fan) i would like to. The factory has remained silent, although they are aware of the problem.....
So all GP, Sport, Scrambler riders, please check the weld regularly - Hagen's broke while doing 180 km/h - over 110 miles - so he was very lucky to survive.
Painter
Posts: 123
Joined: 12 Nov 2015 20:57
Location: Birkenhead uk

Re: Broken Swingarm

Post by Painter »

Hi
Thanks for this important update,
This is potentially a time bomb for some of us not easily forgotten at 90 mph.
See photos of my swinging arm around the pivot point on the shock mounting side, the images are top and bottom.
Appear to be convex, although the lower weld is not so reassuring.
It would be good if other forum users could photograph there's, we might save a perilous incident.
Cheers Steve
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Maurizio_Granpasso
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Joined: 08 Aug 2012 12:26
Location: Italy

Re: Bronken Swingarm

Post by Maurizio_Granpasso »

Painter, can you attach a better picture?

Now we have reports of a total 8 bikes with a broken swingarm (4 in Italy, 3 in Germany, 1 in Netherlands).
We think it's about 1% of all Granpasso, Scrambler and Sport.

This is another broken swingarm from a member of our forum.
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MickeyMoto
Posts: 2415
Joined: 22 Nov 2008 17:41
Location: Even further oop North

Re: Bronken Swingarm

Post by MickeyMoto »

A recall required?

This could finish Morini.
Painter
Posts: 123
Joined: 12 Nov 2015 20:57
Location: Birkenhead uk

Re: Bronken Swingarm

Post by Painter »

Hi
I had trouble uploading pix with my iPad, so I will use my desktop, later today.
Trying to be a bit more objective here, how much of a real problem is this ?

I am unable to read the German study, to ascertain the full extent of the problem, which might make me more paranoid.
My thoughts are, it's a great bike, nothing else on the market comes close even the new crop of overblown jap and European adventure old gits bikes ( I am an old git). The real pleasure of owning a morini is the simplicity and purity of the design, no abs or traction or keyless etc.
So, what do we do, perhaps refabricate around the pivot point, with bracing running down each arm, custom build another arm, several companies could do this, modify poss a 999 arm which had a similar dog leg.
Any ideas or views from other members....

Cheers steve
Painter
Posts: 123
Joined: 12 Nov 2015 20:57
Location: Birkenhead uk

Re: Bronken Swingarm

Post by Painter »

Hi Maurizio

Please see attached pic of my 09 GP swinging arm, from the shock side.
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MickeyMoto
Posts: 2415
Joined: 22 Nov 2008 17:41
Location: Even further oop North

Re: Bronken Swingarm

Post by MickeyMoto »

Painter wrote: Trying to be a bit more objective here, how much of a real problem is this ?

I am unable to read the German study, to ascertain the full extent of the problem, which might make me more paranoid.
Only a problem if it breaks and you crash. Yes, the bikes are fantastic but surely with 8 broken something must be done?

I own a Corsaro so hopefully does not apply to me, but I would not contemplate one of the affected models now until this is resolved. If I have read the report correctly Morini have been informed.

Is the 91/2 and 111/2 swinging arm different?

Mike.
Painter
Posts: 123
Joined: 12 Nov 2015 20:57
Location: Birkenhead uk

Re: Bronken Swingarm

Post by Painter »

Ok, I think this is going to run and run
Are the stress fractures exacerbated by overloading, riding two up with panniers or very heavy riders.

For my part I travel light and never ride two up or use panniers, been their done all of that.

This issue is not going to stop me using the bike, but I will contact the factory and see if any headway can be made.

I might take the arm off and check it properly and see if it can be strengthened, I will let you all know my progress.
Cheers Steve
Painter
Posts: 123
Joined: 12 Nov 2015 20:57
Location: Birkenhead uk

Re: Bronken Swingarm

Post by Painter »

Hi
I have had an email back from the factory, reassuring me that the stress fractures (quote) represent 3 in 5000,representing 0.5% that they are aware of, and that the component has been tested under severe loads which would be difficult to reproduce in normal riding conditions.
So there you have it or not...
In my opinion its good to know there might be a potential issue on some bikes , we need to keep an eye on this and relay and update any failures to the factory, they appear quite open and are quick to respond to emails which is good.
I have asked them if they would replace any fractured swinging arms may they arise, on our UK bikes.

Hope this helps
Cheers steve
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corsaro chris
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Joined: 13 Jul 2006 21:28
Location: Berks, UK

Re: Bronken Swingarm

Post by corsaro chris »

Steve, all;

This is a vital issue for those of us with GPs, and sincere thanks to Maurizio for raising our awareness. A good example of the collaboration within the Morini community! Also thanks to Steve for raising this so promptly with the Factory (and all credit for their response)...

As you say not a trivial issue, but with eight bikes out of a possible 5,000 (thankfully not the 800 implied by Maurizios' initial report) the percentage failure rate is 0.0016% [8 divided by 5,000] - if there are no more reported failures. One UK-registered GP (in camo livery) suffered a crash last year, and appeared to have a bent swing arm - was this the weld or some other machine / rider failure? There are about 20 other machines in the UK with this swing arm - 15 GPs, a couple of Sports and possibly 3 Scramblers that I'm aware of.

I am concerned, but it would be some comfort if we could know the following for all 8 failures so far (and this might be in the report);

1. How old were the machines that experienced this problem
2. Was each failure experienced by machines regularly subjected to high speeds or off-road riding
3. Were they often used with luggage and two up (I've done over 6,000 miles on my previous GP in that condition, for example)
4. Did the tests replicate the types of twisting motions experienced by the arm under riding conditions or were they carried out on a rig in the laboratory without the loading imposed by a shock absorber located asymmetrically

I'm not an engineer, or in any way qualified (I'm sure that one will be along shortly...) and as I say, the German report may address these questions. I'll just wheel the GP out, wash it down and crawl under the rear wheel now. If I get a picture I'll post it here.

To answer Mikes' query - Corsaro and the 9½ / 11½ machines have a different swing arm; the Corsaro appears to be a one piece casting which is massive and appears very well braced, and the 11½ uses a steel tube fabricated construction from memory.

Never has the sign-off 'Good Riding' been so appropriate

CC
"I'll use the Morini"
MickeyMoto
Posts: 2415
Joined: 22 Nov 2008 17:41
Location: Even further oop North

Re: Bronken Swingarm

Post by MickeyMoto »

Is the GP arm aluminium? The fractures are like fatigue failures..

Just because 'only' 8 have broken is not an excuse for complacency. Anything that could lead to a catastrophic failure must be investigated. I would say that maybe there have only been 8 because most bikes are not used to the full envelope of performance.

Still not buying one!

Mike
Painter
Posts: 123
Joined: 12 Nov 2015 20:57
Location: Birkenhead uk

Re: Broken Swingarm

Post by Painter »

Hi to all
Thanks to Chris for the more in depth analysis of riding and testing.
We have no way of knowing other than fabricating a new arm or modifying the existing one.

I spoke with metamech swinging arm manufactures, re braceing around the pivot points, this is something I would only consider if we get more proof of the liability, just waiting to get more photos to them of the areas around the pivot point as they thought it a little tight, I am inclined to agree.
Anyone up for a custom swinger, I would lower mine by 30 mm as well,

It would not be as nice as the hydro formed cast original but, peace of mind, worth it in my opinion as there is nothing out there at any price close to the granpasso and I have owned most.

Any suggestions on a way forward?

Cheers steve
norbert
Posts: 750
Joined: 15 May 2007 15:15
Location: Lübeck/Germany

Re: Broken Swingarm

Post by norbert »

As far as I know the problem afects the Scrambler, Sport and Granpasso.

Anybody has an idea where these oficial 5000 units are or have been sold? Perhaps in India :roll:

norbert
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