Aonther Scura clutch broken

[jrt]

Hex head and no, not with a ratchet/socket. Maaaybe with a spanner, but I'm skeptical. I'll put up a picture in a couple hours.

J

[Paul Minnaert]

I just found 2 nice flywheel pictures in a german forum. This is a ergal flywheel, made to be used with the original 2 plate clutch. It didn't last long.:-(

[Baldini]

Paul,

 

Do you know what happened with this flywheel? The bolts have sheared? There appears to be no impact damage on the outer edge - did the crank spin in the flywheel? Is it known did the cracks come before the bolts sheared? Thanks.

 

KB

[richard100t]

I just found 2 nice flywheel pictures in a german forum. This is a ergal flywheel, made to be used with the original 2 plate clutch. It didn't last long.:-(

44357[/snapback]

Ouch :!: Thats the same flywheel/clutch setup as mt Rosso Mandello right? Did it say what the cause of the damage was? Oh well I just hope its one out of thousands of good flywheels <_>

[Baldini]

...Thats the same flywheel/clutch setup as mt Rosso Mandello right?...

 

No. Rosso Mandello has the single plate clutch, with ali flywheel. There have been some instances of the single plate clutch breaking on Scuras, (but that is not necessarily the same unit as on your bike). The flywheel in Paul's pic appears to be an ali replacement unit for the std Guzzi twin plate clutch.

 

KB

[richard100t]

No. Rosso Mandello has the single plate clutch, with ali flywheel. There have been some instances of the single plate clutch breaking on Scuras, (but that is not necessarily the same unit as on your bike). The flywheel in Paul's pic appears to be an ali replacement unit for the std Guzzi twin plate clutch.

 

KB

44370[/snapback]

Thats a relief. If that happened to my bike I think I'd

[Paul Minnaert]

this one was only maybe 1000 km old. What the owner thinks is that the bolts presure , combined with alu softness, makes the alu flow away where the bolts are, so the come loose, that will end the clutch in no time. The breakage paterns look like the failed single plates, around the center, and acoss

[richard100t]

The damage stayed contained in the tranny housing this time? No blowouts?

[Paul Minnaert]

yes no further damage

[Baldini]

I notice the bolts have a washer each. The RAM I put in Tonti came with one large steel washer that sat under all the bolt heads.

I presume that flwheel is not original Guzzi - were bolts correctly torqued when fitted? From what we've seen the problem seems to stem from bolts coming loose rather than flaws in flywheel material, although compression of the material itself maybe the reason the bolts come loose?

 

Do you run steel twin plate in your Daytona Paul?

 

KB

[luhbo]

I just found 2 nice flywheel pictures in a german forum. This is a ergal flywheel, made to be used with the original 2 plate clutch. It didn't last long.:-(

44357[/snapback]

 

The bolts all have sheared, in deed! I would post such pictures more carefully, to be honest. You have or at least share no information how the clutch was mounted, who did it, with what tools, what torques and so on. You don't even tell us the source of the pics!

 

I think it's just a wonderfull example of how desinformation works! This clutch is sold since many years, as you probably know, without any problems or even safety issues as I think to know. I do know that it is shit anyway, as even the steel original shows too much wear. Also it is seldom a good practice just to change the material without any design or mounting adjustments.

 

Hubert

[Paul Minnaert]

Do you run steel twin plate in your Daytona Paul?

Yes, orginal with better plates to withstand the power.

 

@hubert

 

This pictures are from Ernst@ world-of-guzzi forum.

http://www.world-of-guzzi.de/ivb13/index.php?showtopic=8193

You're correct that this is an aftermarket flywheel. The problems are from years ago, and Ernst showed the picture in an discussion about lighting flywheels.

Pretty common knowledge about these ergal flywheels, is that there are 2 versions, and that the lightest one won't last long.

I found the resemblance between the failing scura clutches and this remarkable.

The forces on both centers are roughly the same, and still I have no defenitve answer how the failure goes, first loose bolts and than the cracks in the aluminium? or else?

[jrt]

That sounds like a reasonable hypothesis. Two alternatives are materials defects (has anyone looked into that?) and uneven loading. The latter is unlikely I would think.

Jason

[dlaing]

I

I think it's just a wonderfull example of how desinformation works!

Hubert

44426[/snapback]

It is only disinformation if Paul is lying or we rush to judgement against the rider, the installer or the manufacturer.

It is a motorcycle clutch and not a car clutch, so yah, we are going to have more problems.

Our clutches are lighter, we rev the heck out of our bikes, and shit happens.

We can hypothesis all we want and until we irresponsibly blame someone, there is no disinformation.

But it is good advice not to blame someone or some manufacturer, without solid evidence.

This could have been prevented possibly through the use of a ring to evenly distribute the bolt torque. Possibly the torque was off too much between bolts. Maybe they should have used Loctite®. Possibly popping the clutch is a bad thing to do to a guzzi and the rider MAY have abused the clutch.

Certainly the product could have been made heavier and reduced the chance of it cracking the way it did. This is a compomise that is engineered into the clutch. It is not bad that they do this unless we see too many failing, which is apparently not the case with this manufacturer.

Of course if your clutch is the one that fails, you might say there are too many failures....But you also have to look at it and think what you could have done wrong.

 

Oh sh^t I am late for work

[luhbo]

Hi dlaing,

 

I mean disinformation does not mean lying. I call it disinformation, when correct informations are shared, but either in a compromising context or without any further but important informations that were available and so on. Maybe this fellow killed this clutch with excessive wheelies (probably not, of course) but that's what I wanted to say. And look at the bolts again, these were 10.9 ones. The mechanic must have done something wrong IMHO

 

Hubert