Manufacturing error or impending doom

I recently changed the brakes on my Bacchetta bella from disc to rim brakes. Since I don't tour with it at present, and there are no hills here in Florida, I decided to save a bit of weight and put a pair of brand new brake calipers I've had sitting around to use. I took it out on a ride today and noticed a strange pulsing in the rear wheel when I applied the brakes. When I stopped and inspected the rear wheel I could see that there was a slight discontinuity where the rim was welded into a circle.

At first I thought it might just be a manufacturing defect that I've never noticed before, since I have been using disc brakes. I figured I'd just dremel it smooth. But on closer inspection it seems that the wheel might be on the verge of fracturing. Unless someone tells me that this is a common quality control issue with aluminum rims, and that I'm safe to smooth it down, I'm inclined to not chance it and get a new wheel. I have a few other rim brake aluminum wheels around, and I can't see or feel anything like this on them.

Opinions?

 

It's not too uncommon on inexpensive rims. Many rims are pinned and have such a joint, but most are smoother than that. I have had such rims with a bad seam. The thumping is annoying, and does lead to momentary grabbiness, so I would try to sand it smoother. I doubt it's an indication of eminent rim failure.

 

Well that's encouraging. I'll need to smooth it for sure since it is acting like a rotating knife, and it will shave down the brake pad. I think I'll over inflate the tire a bit and let it sit in my garage a day or two, and see if there are any changes just to be sure.

 

I have assumed that rims were welded where the extruded ends come together. I had never heard of the pinned or sleeve joining method, but now that i've looked that up, that totally seems to be what I'm looking at. Well, you learn something new every day!

 

However, if the thumping continues, then you might want to removed the tire/rim strip and take a look in side just for the "knowing" and then consider getting a new wheel, keeping this one as a spare.

 

What Steamer said. Pinned rims always have a seam and some are much worse brake thumpers than others. Most Alex rims I have owned were brake thumpers. Not sure why the Alex rims have a more protruding seam than other rims unless they have poor quality control. Anyway, I have never had the brake thumping cause an issue other than be annoying.

It's funny OP mentioned he went to rim brakes from disc brakes to save a little weight. I recently did the same thing on my Cycle Genius LTX. I had a pair of Avid SD7 V-brakes sitting in my parts bin and decided to use them on my LTX in place of the disc brakes. Another reason is I find disc brakes fiddly. With V-brakes once I have them setup I can pretty much forget about them. I also live in a flat area and never ride in the rain unless I just happen to be out riding and get caught in a pop-up storm. For my type of riding the V-brakes are more than adequate.

 

While I defer to those of greater experience, I'd err on the side of caution. I notice that the decal over the seam is deformed, which may indicate that the seam is "working" under load. If it's pinned, it may last awhile, but I wouldn't trust it, especially not here in the Pothole Center of the Continent.