Recent odd failures on bikes that have come into my shop...

[Speeddog]

'06 S2R800, 22k miles

Brought in for service, owner mentioned odd noise/clunk from driveline.

Noticed that there was something trapped in the safetywire on the axle clip.
Closer inspection determined it was a piece of the nut.
That's odd.





Also, there was swarf appearing at the intersection of the cone and the wheel.
Visible in the above pic, here's a closer pic and I've circled some of it.
This isn't looking good.





Here's the nut, piece missing, also note the ragged lower edge of the cone:





Other side of the cone.
Ow.





Mating surface of the wheel.





Finally, the back side of the wheel, where this ugly little party got started.
When the wheel was installed, the pegs on the hub went into the big open slots, rather than the holes.
Disturbingly easy to do.





Mating part of the hub, just to help clarify it a bit for those who haven't seen an SSS wheel setup.

[Duck-Stew]

Peeples is dumm sumtimes I sweers... 

That's a good one Speeddog.  I haven't seen that failure before! 

[♣ McKraut ♣]

we had someone locally do that a while back...  i'm really surprised i haven't done it myself yet actually       makes me think i should just grab a spare hub setup from the parts for sale section just in case.  i've heard a noticeable (even with ear plugs in) "squeak squeak squeak" for a while when taking off from a stop...and wondering if that's coming from the hub area.

[mitt]

WHY didn't the wheel / hub designers make that interface pok-a-yoke (1 way to install - error proof)!  It would have been soooo easy with a web of material in the wheel pockets or extra pins in the hub...

This is more than 3 times I have seen this on the dmf, although this is the worst example of wear.


mitt

[Langanobob]

Also looks like pipe wrench or Channelok pliers teeth marks on the nut in the first pictures.  Tells something about the care taken in the past installation.

[Christian]

Exactly. It's not "fool proof" but the wheel clearly only goes on one way. A lazy or bad mechanic is going to screw things up no matter what.

[jim_0068]

To over engineer something to help out the stupid is a waste of an engineers time imho. Next time, just do it right.

[Popeye the Sailor]

To over engineer something to help out the stupid is a waste of an engineers time imho. Next time, just do it right.

If you can easily assemble it incorrectly in a way that is not noticeable and causes great expense, it was never engineered in the first place.


It would not be difficult to make it so that rim fits on one way only.

[Christian]

True, but the 5-spokes are specifically trying to be lightweight.

There are four posts on the hub, and four post holes in the wheel. Any mechanic worth their salt would look at that and install accordingly.

We're getting a bit off topic here, though. We could start a new thread for proper bickering.

[Speeddog]

If you can easily assemble it incorrectly in a way that is not noticeable and causes great expense, it was never engineered in the first place.

It would not be difficult to make it so that rim fits on one way only.

That's the real problem with this.
It's easily avoidable from the very start, at the factory.

The wheel could be just as light, and still prevent incorrect assembly.

[Popeye the Sailor]

That's the real problem with this.
It's easily avoidable from the very start, at the factory.

The wheel could be just as light, and still prevent incorrect assembly.

It sounds like you may have had issue with it in the apst?

"Finally, the back side of the wheel, where this ugly little party got started.
When the wheel was installed, the pegs on the hub went into the big open slots, rather than the holes.
Disturbingly easy to do."

That true? Because AFAIK, you're considered a truly excellent Duc mech-and I figure if you can almost do it, the process is in need of help.

[Christian]

Okay, MrIncredible - I concede. It's a bad design. You've made your point.

[corey]

I'm sorry, but bad design or not, you gotta be paying pretty much ZERO attention to make the beast with two backs that one up.
Do you not even spin the wheel a little after you slide it on? I mean christ, even tightening the nut by hand at first should slide the wheel enough for you to notice something isn't right.... but hey, he probably just air-hammered it on there to about 900ft lbs...

[Speeddog]

It sounds like you may have had issue with it in the apst?

"Finally, the back side of the wheel, where this ugly little party got started.
When the wheel was installed, the pegs on the hub went into the big open slots, rather than the holes.
Disturbingly easy to do."

That true? Because AFAIK, you're considered a truly excellent Duc mech-and I figure if you can almost do it, the process is in need of help.

No, haven't done it or almost done it, but I always take care to ensure that the wheel is going on correctly.

Yes, I'd rather that Ducati had done the job right at the start.

I'm sorry, but bad design or not, you gotta be paying pretty much ZERO attention to make the beast with two backs that one up.
Do you not even spin the wheel a little after you slide it on? I mean christ, even tightening the nut by hand at first should slide the wheel enough for you to notice something isn't right.... but hey, he probably just air-hammered it on there to about 900ft lbs...

I haven't tried an improper assembly to see how it looks, but....

The wheel will sit flat, as it's resting on the shoulders of the pins.
There will be a gap at the back for that same reason.
It might not torque down with a proper 'feel'.

A lot of picking up on that comes with experience.
I've been working on cars and bikes for 40 years.
Learned from my dad, who's a mechanical engineer.
I'm a mechanical engineer as well.
So stuff that's obvious to me isn't necessarily the same for other folks.

[junior varsity]

this thread has some awesome wowza's.