Ilmberger Hugger Failure - Page 2

roger albert · 09-30-2002, 08:56 AM

Youch,

I do need to look mine over too then, as I've had it for a long time.

Roger, Miles on your hugger?

The fracture was shortly outside of the CF reinforced region, so about where you'd expect some sort of vibrating/resonance fatigue failure.

What's interesting is (and this may just be poor pic quality) the multiple apparent colors at the fracture. The lower 3/4 looks to have happened over time, and the upper 1/4 snapped cleanly when it could no longer handle the load. Anyway, there could well have been a stress/strain/corrosion thing that happened with the crack propagating out over time. i.e. a small nick or manufacturing/finishing defect there _could_ have been the issue, rather than simple fatigue. Tough to tell from the pic. There are a couple good materials guys on the board, so maybe
one of them will chime in.

Let's hope.

Roger

DCooper · 09-30-2002, 11:19 AM

Apparenly not an isolated event. I saw an S at Laguna sporting only the mounting arm attached to the caliper. Borken in the same location.

Roger Justus · 09-30-2002, 02:02 PM

I got an e-mail from Mitch Herman today as he had heard back from Julius Ilmberger. Not bad response time as I had only reported this to Mitch on Thursday. They were sorry for the trouble this had caused me and are shipping me a new hugger.

The gist of Ilmberger's thoughts were that: if you do not remove the black plastic OEM shock muck protector piece that it can cause this problem and that everybody should make sure they do this. He said it happened to his own bike. I am enclosing the gist of his message:

Hi Mitch,
we are very sorry what happend. I was able that we answered you at this time, because we were not here.
I think I know what happend, because on my bike it was the same. If you mount the rear fender, you must remove the original shockabsorber cover (its the black plastic thing who is mounted with two sreews on the rear shock absorber). If you dont move this part, it will hit the rear fender if you drive with the bike. If the fender goes on the cover the back tyre damaged the rear fender.

--------------

I answered Mitch back as follows: Thanks for the response. Yes I had the original black plastic shock cover in place but the Ilmberger cover didn't hit it. A couple of the R1100S owners from the Pelican Parts Bulletin board think it is a resonance fracture which occurs in instances where the metal part of the hugger makes contact with part of the caliper body. In one of my pictures that shows the break you can see a small nick off the paint on the caliper where the metal part of the hugger arm made contact when torqued to specification. Some think that this point contact might be able to generate stresses at the site which fatigue the metal which results in the fracture. You may want to pass this information on to Julius for his consideration. I will certainly mention his advice to others about ensuring to remove the OEM small shock protector piece."

I noted that still have confidence in his product and was encouraged by them wanting to make this right.

Lennie notes that like with all things, there will always be some failures. Mitch had said that he had not seen a failure in all of the huggers that have come into the US.

So, consider checking your hugger and its installation carefully for clearance and any signs of fatigue. If there are more hugger failures I imagine we will be hearing about them on this board. All the best,

markjenn · 09-30-2002, 02:17 PM

It's great they got back to you, but I doubt the black plastic shock protector is a factor, at least if there is as much clearance between the hugger and the plastic as there is on my bike. It's a solid 3/4" and I doubt there are circumstances where it would make contact.

My $0.02 is that when you get an item mounted the way the hugger is, you're always running some risk the hugger might start resonating at a particular frequency, given that it is unsprung and that the tire and wheel assembly will likely offer a complex source of periodic inputs. If the thing starts vibrating, I could see it developing fatigue cracking very easily. And the hugger probably has several different ways it can vibrate, both due to translation and rotation. Throw in a contributing stress riser due to brake caliper contact and you have everything you need for failure. It may be a statistical thing - some percentage of huggers will just happen to resonate at a frequency that can be excited by the tire/wheel and failure may be inevitable.

On the positive, we appear to only have one known failure and the thing looks fairly overbuilt to me, so maybe it was a defect and the thing has sufficient fatigue margins built in to last indefinitely. But my money is that some percentage of non-defective units will eventually fail.

I'm going to be going over mine with a fine tooth comb at tire changes and if I see anythign that looks suspicious, it will go into the trash. Keeping my rear shock clean is hardly worth risking a wreck.

- Mark

roger albert · 09-30-2002, 02:19 PM

Interesting that another one was seen at Laguna.

I'm not sure we're seeing the same failure mode
(or at least not root cause) that Julius did, but, it
would seem to be a large coincidence. I know I
really like my hugger, but it does vibrate a good
deal. I'm sure those amplitudes are sometimes
large enogh to more than eat into that 1/8" clearance.

I'm more and more convinced that it's a stress fracture
caused by contact with the caliper. Almost no way
the corresponding markings/abrasions are coincidence.

One a little nick starts, you don't even need subsequent
contact for the stress riser to eventually split it up.
It looks like it did just that through about 3/4 of the
metal, and then it just snapped. Doesn't look to be
because the arm was too weak, so much as it allowed
contact. Ironically, a smaller arm (radiused as was
suggested here -- good call, btw, imo) might have done
a better job. There are many many bolt and fastener and
beam applications where things are made more durable
and stress tolearant by _removing_ material from the
appropriate place.

Odds are, a little felt or cork self-adhesive pad could have prevented it. (no nick, no real stress, other than perhaps
fatigue over a MUCh longer period of time) I already have
a felt pad than prevents mine from making other contact,
but I should go back and add another this eve near the caliper.

Thanks for sharing this with us Roger J. Very valuable.

later
roger

Roger Justus · 09-30-2002, 02:26 PM

Roger, Roger

Roger Justus · 10-02-2002, 02:57 PM

Mitch has heard further from Ilemberger who wants to get the hugger back to examine and probably send it to a lab. I am sending it back rather than just chuck it. I had given Mitch the link to this thread and it seems that Ilemberger wants to go beyond the possibility of it perhaps just failing from just striking the OEM plastic shock splash cover.
-----------------

Mitch enclosed Ilemberger's response:

Hi Mitch,
thank you for the Email.
In normal situation the plastic cover didnt hit the hugger, but if you drive hard and the rear suspension goes in very deep, I think than it can be, that the hugger hits it.
But it can be also resonances.
The only way to check it, is to see the part. So please ask the customer if he can send it back to us. Because I want to check if there is any different problem. Please understand that its very hard to say something, if you dont have the part in the hand.
So its very important for me to see it, because if there is something to change on the part, you know we do it.
---------------
Thanks for the helpful input from this Board. Looks like the distributer and the maker will be taking it into consideration.

Dave Grinsel · 10-05-2002, 08:20 PM

I have the same hugger and it broke leaving the parking lot from work on Wednesday. My bike made a strange noise and wobbled a bit as though I had left my side stand down. I stopped looked around and found nothing so I continued home. As I was out of town the next few days, I didn't check my bike until this morning before a Saturday ride. To my surprise, no hugger. All that was left was a small stub of a bracket.

I purchased mine this past winter, torqued it properly when installing, and it lasted only 10,000 miles. Fortunately, I was only going about 15 MPH when it broke. I don't think I would feel safe installing a second one.

tominator · 10-05-2002, 08:28 PM

I like the look of the Ilmberger...but this is the one I own.
Good thick bracket, excellent water protection and stays secure!

And the other side!

Made in France

Cheers
Tomas

pdonnell · 10-05-2002, 08:35 PM

Tom,
.
I don't think its sized for the Staintune Exhaust or a 5.5 rim? Am I wrong on this?

tominator · 08:56 PM

Pat,
Don't know about the staintune, but the hugger is made for both the 5 inch and 5.5 inch wheel. I tried it....That's what's great about this hugger.
Only real issue I have had is my rear spring is getting tired and when two up riding+camping gear, hugger does get a little close to the Vanderlinde under the seat.

Here is the link to a guys site in France. Has some more pics of the French Hugger.
Whats different now is the newer hugger does not include the disk vent. Instead has a wide mounting bracket, leaving out the slot for brake venting. Who uses the rear brake anyway?

French Hugger pics

Cheers
Tomas

R-monster · 10-06-2002, 12:57 AM

Greetings,

I had the Hugger that Tomas is mentioning from France. I looked long and hard at all the available huggers at the time I purchased the French made unit. The hamburgler ( Ilmberger) hugger mounting system looked real flimsy too me and had absolutely no real coverage for the elements. It does look way sexier for the time it does work though!

Most of the hamburger huggers will fail over time due to the way it is constructed. The only caveat with the French hugger is dealing directly with the Manufacturer in France who speaks no english.

HE WILL SEND YOU A HUGGER IF YOU PRE-PAY HIM.

I hope Illmberger stands behind the product and gives everybody new units which will need to be checked frequently. Below is the old thread on TCV and its offerings:

French Hugger

It is quite apparent from the different mounting system TCV employs that you will obtain better durability .

Busabim

roger albert · 10-07-2002, 08:28 AM

Hi all,

Roger, thanks for keeping us updated. Following this one closely.

Later
Roger

Kam · 10-07-2002, 02:48 PM

So what are you guys thinking? Take the burgler off? Check it every time you get on the bike? Fzuck it and throw caution into the wind? I personally wish this would all go away, but I like my little hugger.

VR4-Quest · 10-08-2002, 10:54 AM

I noticed my Illmburger rubbing on the stock rear plastic shock protector, most are thinking that it vibrating could no way touch it, but under a load (1 or 2 up) and deflection (hitting a bump), the 2 can rub (my hugger showed sum rubing and wear). Combine that with the vibrations due to the single cantilever type design, and a small nick or crack from the caliper, and the forces created (the moment transmitted when the hugger hits the stock plastic shock guard - the force times the distance which is from the point of contact back to the support - things could get pretty big).

I dont think any one of these events would have caused the failure, rather the combination of them.
I will definitely be checking mine!

roger albert · 10-08-2002, 10:59 AM

Hi,

The movements of the hugger are pretty large. I have no doubt they hugger could hit that little black piece of plastic. Otoh, if I had a stock shock that had that minimal (but useful) bit of protection, I wouldn't have put the hugger on in the first place.

Maybe ShoxSox or similar would be good. Certainly lower mass.

roger

Kam · 10-09-2002, 04:28 AM

ShoxSox?????? What is it?

roger albert · 10-09-2002, 07:17 AM

Just kind of a condom sort of affair, typically neoprene, that
goes over the spring and shaft to keep unwanted debris off.

Can't find my notes on the ones I was thinking of, but here's the link to a nylon one (3 sizes) from Traxxion:

http://www.traxxion.com/products.shock.shocksocks.shtml

hth
roger

Roger Justus · 10-11-2002, 12:18 PM

Well.....received my replacement hugger this week and fitted it to the bike. Sent the old one back to Motorsports Imports for their study. The new hugger now has a manufacture date on the underside (month, day and year in my case 03/17/02) and the name of person (presumably who made it). Also had an "R2" on it. Don't know if that refers to a particular edition of the hugger or not. The piece went on easily with no fuss or allignment problems.
I noticed that the L - shaped metal bracket that mounts to the brake caliper has a more open (greater) angle by a about a couple of degrees from my older failed 2000 vintage hugger. This elevates the upper part of the "L" of metal bracket so that it easily clears the caliper body. Some on this board think that such contact might be at least part of the problem if this was a resonance-type failure. The different cant of the bracket also seems to put the hugger slightly higher and more towards the rear of the bike than the old one did. Possibly less opportunity to move forward and hit things? I also took off the old OEM black plastic shock splash guard as they suggested. Will keep an eye on it and take the hugger off for track days. Rather err on the side of caution when there are large brake forces. Hope they take advantage of the constructive wisdom of this board to improve their product and develop some clear instuctions for mounting and use. All the best.

Chris Canning · 10-11-2002, 02:30 PM

Posted mine direct to Ilmberger in Germany from the UK had an e-mail yesterday saying a new ones in the post,will be interested to see the difference,and particularly as my failure was different from the others on the board.

Chris