CARC

[Chris Wilson]

I will never question CARC engineering again!

[docc]

Collision damage?

[Chris Wilson]

I believe that it was rider error in mud!?

Even so, it should not have happened.

Chris.

[LowRyter]

What happened? 

Mud? Should not be. 

Hard accident!  Or?

[fotoguzzi]

That happens to BMW's

 

[Lucky Phil]

4 hours ago, Chris Wilson said:

I will never question CARC engineering again!

Really. Why?

Cracking emanating from a wheel speed sensor retaining clamp tapped hole leads to this result. 

Ciao 

[ScuRoo]

I once knew a woman who turned inside a horse float with rubber flooring. As she swivelled round on one leg her foot stayed planted & her ankle just broke instead!
Bloody hell! 😳Foot pinned & fused lost all function...

 

Oh yeah, she was a stinkin’ huge whoppingly fat lardy lard arsed heifer too!!

 

I mean, sorry, she was a bit overweight. 🧐

Just sayin’. 

[pete roper]

4 hours ago, Lucky Phil said:

Really. Why?

Cracking emanating from a wheel speed sensor retaining clamp tapped hole leads to this result. 

Ciao 

Yup, but I know of four cases of this issue, all from the same model run, in a period of twelve years. From memory it was one run of 2012 Stelvios but don't quote me on that. The factory, naturally, denied it. I keep an eye on this shit because I'm interested.

I think the BMW issue was considerably more common.

Nobody is perfect but the Bavarians are much worse than Guzzi.

[Chris Wilson]

2012 models Pete?

My Bellagio is a 2012!

[pete roper]

As with so many things it seems to have hit Stelvios, and as I said, I know of four. In fact I sent a bloke in South Africa a swingarm when his bust because he was getting stonewalled by the importer. I know of two in Oz. Both of which were denied warranty because they had been 'Abused', (I have it on good authority that they weren't, in any way shape or form.) and the last one was in Canada and resulted in serious injury and it went to court. I do not know the outcome.

[Lucky Phil]

55 minutes ago, Chris Wilson said:

2012 models Pete?

My Bellagio is a 2012!

It's a simple preventative fix anyway. Drill the threads out of the hole and use a Ducati well nut for the clamp instead. Remove the stress raiser. Basic engineering. My main point was don't get too cocky about the other guys engineering failures, nobody is immune.   

Ciao 

[Lucky Phil]

52 minutes ago, pete roper said:

As with so many things it seems to have hit Stelvios, and as I said, I know of four. In fact I sent a bloke in South Africa a swingarm when his bust because he was getting stonewalled by the importer. I know of two in Oz. Both of which were denied warranty because they had been 'Abused', (I have it on good authority that they weren't, in any way shape or form.) and the last one was in Canada and resulted in serious injury and it went to court. I do not know the outcome.

Due I guess to the off road stresses and maybe a stiffer shock spring and greater swingarm loads?

Ciao

[pete roper]

Not seemingly with the ones I know of. The Stelvio's suspension is also longer travel and 'Plusher' than that used on the supposedly purely 'Road' models but it was Stelvios that had the breakages.

Yes, it is thought that the stress raiser was from one of the hose clip holes. I've never been close enough to one that it's happened to to know, but it makes perfect sense.
 

It's also one of the reasons I think fitting a sidecar to a CARC bike is a really silly idea but people do that as well.

[Chris Wilson]

9 hours ago, Lucky Phil said:

It's a simple preventative fix anyway. Drill the threads out of the hole and use a Ducati well nut for the clamp instead. Remove the stress raiser. Basic engineering. My main point was don't get too cocky about the other guys engineering failures, nobody is immune.   

Ciao 

Hi Phil, 

And my main point is that Guzzi had to introduce a point of failure with the secondary operation of added perforation, that is to say, without adding the hole the design is sound.

The BMW design needs no such benefit in order to fail, it's purely a lack of cross section and that is definitely something that could not leveled at a CARC drive.

Tear along the dotted line failures are more easily rectified by not adding the dots in the first place, where as lack of material or section involves a new cast to be made.

Anyhow, from a basic engineering point of view a single sided swing is poor design and is (on road and off road bikes) a purely a nod to fashion.

As we all know it came from endurance track racing where rapid tyre changes outweighed the bizarrely monolithic builds needed in order to combat forces imposed, mainly twist.

Rapid tyre change with my bike is a joke, no centre stand and muffler removal are just two issues to be resolved before getting anywhere removal.

On my K75, yes it was possible to remove the rear tyre more easily but it was hardly classed as 'rapid' dogding around a scaldingly hot stainless muffler that lay across the diameter of the wheel.

So again, I will never question the strength of the CARC system and as its impossible to prove a non failure one must use failures of similar to prove the concept.

Chris.

[Lucky Phil]

10 hours ago, Chris Wilson said:

Hi Phil, 

And my main point is that Guzzi had to introduce a point of failure with the secondary operation of added perforation, that is to say, without adding the hole the design is sound.

The BMW design needs no such benefit in order to fail, it's purely a lack of cross section and that is definitely something that could not leveled at a CARC drive.

Tear along the dotted line failures are more easily rectified by not adding the dots in the first place, where as lack of material or section involves a new cast to be made.

Anyhow, from a basic engineering point of view a single sided swing is poor design and is (on road and off road bikes) a purely a nod to fashion.

As we all know it came from endurance track racing where rapid tyre changes outweighed the bizarrely monolithic builds needed in order to combat forces imposed, mainly twist.

Rapid tyre change with my bike is a joke, no centre stand and muffler removal are just two issues to be resolved before getting anywhere removal.

On my K75, yes it was possible to remove the rear tyre more easily but it was hardly classed as 'rapid' dogding around a scaldingly hot stainless muffler that lay across the diameter of the wheel.

So again, I will never question the strength of the CARC system and as its impossible to prove a non failure one must use failures of similar to prove the concept.

Chris.

Well Kevin Cameron and I might have an interest with regard to that that statement. From a technical purists perspective you have an argument but the reality is Ducati have won quite a few WSB Championships with a single sided arm and as Cameron postulated the single arm may well have an advantage in some ways with regards to tyre wear. Not everything that's superior on the drawing board translates to the real world as KTM have proven with the unfashionable steel trellis frame that has become a MotoGP winner.  As for your "my main point". I don't recall reading that before this quoted post. Remind me where you previously posted the tapped hole crack instigator as your "main point"? Seems something you've just become aware of to me. It doesn't matter what the engineering "weakest link" is the fact that it exists is what counts as I have experienced in over 40 years in aviation and motorcycle engineering. You don't have engineers staring into a smoking hole in the ground saying "but it was only a small engineering error" They all count.  

Ciao