rear wheel crack?

[slow1]

I just noticed what appears to be a stress fracture where the spoke meets the rim. Tire holds air (I'm religious about this) and no bubbles form when soapy water is applied. Is this normal or am I'm looking at replacing the rim?

 

Thanks,

 

Sid

'98 r1100rt

[Tony_K]

Wow are you positive they are cracks?

If so REPLACE!

 

Metallurgy has come a long way especially in malleable alloys so that it will not crack...

 

It usually takes a sever impact to fracture so much so that I would think the wheel would not be useable.

 

But I guess anything is possible.

[GordonB]

I'd be concerned of the consequences should that fracture work its way thru and separate the spoke from the rim.

Nice high speed sweeper......Lots of stress on wheel......

[slow1]

You guys are right. I don't like surprises and it's off to the Boneyard.

 

Thanks for the respones, 'tho I'm surpised this occurred.

[Stan Walker]

Pictures, we need pictures....please!

 

Stan

[slow1]

Sorry but I tried to post pictures 2 weeks ago on the Blackbird owners forum and for whatever reason my OS wouldn't upload.

 

The crack is about 3/4" where the spoke meets the rim. From there 4 more "fractures" shoot out toward the rim and stop before it reaches the flange.

 

This wheel is listed as "cast iron" on the parts fiche so maybe advanced metallugy hadn't reached BMW in 1992.

 

Thanks again for the responses.

[slow1]

Update-

 

Wheel specialist today confirmed stress fractures. Cleaning wheels helped avoid a potential disaster.

[nrp]

Please try to post a picture so we all know what to look for. I assume these rims are cast aluminum (& not cast iron?).

[StuGotz]

Cast iron wheel on a motorcycle? YOW!

 

Cast aluminum, yes.

 

How much weight you been carryin' sir??

 

Any fracture in that area usually due to weight issues.

Any road hazard issues usually near edge of rim, and tire will show damage as well.

Casting porosity issues usually get caught at factory.

Anyone heard of recalls on BMW rims?

 

MB>

[E30TECH]

Please try to post a picture so we all know what to look for. I assume these rims are cast aluminum (& not cast iron?).

 

I'd like to see a pic too. I figured that the 'crack' was a spot from the casting, and not an actual crack. Glad you found it!

[Ken H.]

Anyone heard of recalls on BMW rims?

Not only have there never been any recalls, this is the first time I can recall hearing about one that has cracked. Short of a catastrophic impact of course. A one-off anomaly for sure.

[Joe Frickin' Friday]

Anyone heard of recalls on BMW rims?

Not only have there never been any recalls, this is the first time I can recall hearing about one that has cracked. Short of a catastrophic impact of course. A one-off anomaly for sure.

 

I'm curious about this history of this wheel. It's a '98 RT, so there's time enough to have gone plenty of revolutions. I wonder about any hard hits (or, as was asked, how much weight was typically carried)?

[E30TECH]

I wonder about any hard hits (or, as was asked, how much weight was typically carried)?

 

I would think a hit hard enough to cause a crack where the spoke meets the rim, would leave a big impression on the point of contact (not to mention a bent rim).

 

I can't help but think that was due to a bad casting.

 

Hopefully we can see a pic of the damaged part

[slow1]

I'd like to post a pic but can't as explained earlier. It's quite noticeable-you've cleaned your wheel and you see cracks.

Polishing won't remove them and as the Rim guy said, when you run your fingernail over it it "grabs" your nail instead of being a slight bump. The latter usually means just scratched paint. And yes, this just showed up. I did a 525 mile ride on Sat and cleaned the wheels on Sun. Only recall one minor drop in the road on a high speed left hander(Hiway 58, Kern County, CA) causing a slight wobble.

 

Bike has 35k miles, I picked it up at 12.5k. 80-90% of mileage are long trips. I weigh 220# with riding gear and ride solo. Saddlebags have about 15-20# each for longer trips.

 

Earlier responses are correct that the rim is alloy. I was just quoting BMW parts fiche which stated "cast iron rim silver rear". Magnet proved otherwise.

 

A buddy thinks it was a casting issue resulting in metal fatigue lending some credibility that this is an "anomaly" as stated by Ken & Donna. I tend to agree.

[Joe Frickin' Friday]

I'd like to post a pic but can't as explained earlier.

 

email it to me (prestondrake at comcast dot net) and I'll host it/post it.

[slow1]

Mitch,

 

Thanks for the offer. Unfortunately, I didn't take a picture because of earlier problems e-mailing on the Blackbird Owners Forum (heated grip topic). That pic downloaded no problem into Adobe Photoshop, but all I got were "error" messages when I tried to send it. I even tried to send that picture to my Comcast and Yahoo accounts with no success.

 

I dropped it off earlier this morning at the Rim specialist for his inspection/repair and he will get back to me in 2-3 days. I just didn't take a pic considering I couldn't send it. Sorry about that.

[USAF1]

Well...that's slightly wrong. BMW did have a wheel recall, back in the early '80's with the Snow-Flake wheels. Everybody that turned them in received newer "reinforced" wheels.

 

Pat

[nrp]

I recently saw a video of a spoked M/C wheel being tested to failure in a one shot impact. The spokes failed first - and at 90 degrees to the impact point. Two tests - same result.

[Ken H.]

back in the early '80's

I stand corrected. But to my defense, I'm way too young to remember the early '80s.

 

(Or is it I'm way too old to remember the early '80s?)

[scurfer]

This brings back a memory of cracks developing on a certain brand of wheel for the Moto Guzzi Quota several years ago. Can't remember the brand name but it was an issue on the MG boards at the time.

[USAF1]

Mashed green beans have been proven to help with memory retention............

 

Pat