Bead corrosion?

[Daniel Meyer]

A new one on me...never seen this on an aluminum rim in all my years, machines, and miles...

I developed an annoying bead leak on my front wheel a while back...Fairly new tire, didn't do it when first installed...knew I would have to pull the tire to fix it so had pondered running it till replacement. It was only losing a pound or so a day.

Lately it got much worse...so I pulled it down...yanno...ya ought to make sure your tires will at least hold air before a few thousand miles of gallivanting about the country in the hot summer...

Massive corrosion of the bead area on my rim. To the point where white powder went flying when I broke it down.

I had like...10 minutes of free time until July so I simply cleaned the bead of the tire and rim with Emory cloth, and hit the entire thing with bead sealant (essentially, black rubber cement), and put 'er back on. No, it won't glue the tire to the rim...it really won't stick to metal...it just provides a "gasket" so to speak.

I've never had to use this on an aluminum rim. I've never even heard of somebody needing this on an aluminum rim.

Not sure why the sudden corrosion...why now? It's been fine through more than 10 tire changes. Weird. Like I said...never seen it on an aluminum rim.

So...good for now. When I need to replace the skin...probably end of summerish...I'll need to REALLY clean up the inner rim and bead area. Then what? Seal it? Not talking the outside pretty polished area...talking inside the tire and the bead area. Polyurethane maybe?

Anybody seen this? Suggestions?

[biguglyman]

Seen a similar thing on my wife's old van with "alloy" wheels. Guy at Monro said it was due to other places using soap/soapy water to lube for assembly of new tire and bad cleaning practices when changing the tires. I find it hard to believe you would be guilty of THAT. You been riding up north where we salt the roads in winter?

[BonS]

I thought that this link is interesting, if not a little over my head.
http://aluminium.matter.org.uk/content/html/eng/default.asp?catid=180&pageid=2144416698

The article mentions chlorides and water as a culprit. Here in the Midwest, we get a lot of aluminum rim corrosion and subsequent bead seal failure. The roller coaster Winter weather results in lots of ice and a lot of liquid salt and/or thrown rock salt. Warmer weather combined with rain or even a heated garage makes for the perfect storm for aluminum corrosion.

Aluminum is anodized to prevent corrosion but the anodized layer is easily removed with either a high or low pH. so either a salt or an acid can strip the aluminum and leave it exposed to corrosion.

The anodized layer can also be damaged from tire friction/heat and tire changes as it has only a moderate wear resistance.

[hubcapsc]

Soap (pure Dawn, and too much of it) killed a rim on my CR500...

Now I use the stuff-which-must-not-be-googled:



-Mike

[pancho]

Yeah,, I was thinking that it probably had been the last thing that was used to lube the tire and rim  during assembly.

[tonyfan70]

Guess it's not common on bike rims? When I worked tire shops, bead leaks due to corrosion was a non stop problem. Weather would get cold and it seemed like every car with aluminum wheels had a slow leak or four. I'd have to wear goggles and the cloud of corrosion dust would choke you.  I know it seems odd, but Caddy's were by FAR the worst at this and I don't know why. Cleaning the beads and using bead sealer would work..for a while. I'd even have to wire brush the tires to get a good seal, due to flakes stuck to them. Seems I also remember fix a flat doing a number on fancy wheels if left inside too long.

[The emperor has no clothes]

Soap (pure Dawn, and too much of it) killed a rim on my CR500...

Now I use the stuff-which-must-not-be-googled:



-Mike

Thanks for the heads up on that. I've been using soap & water. Not now!