Cracked rim question
 

https://cimg7.ibsrv.net/gimg/bikefor...b9ce73b608.jpg
Pictured is a 36-spoke off-brand double wall aluminum wheel that I purchased off Amazon about two years ago. It's got about 12,000 miles on it. The wheel is true and still runs and appears fine, except for this recent cracking around one spoke hole. Does anyone have any insight? What caused this damage? How much more life is in this rim? Will the double wall make a difference?

1... low grade alloy, and/or poor extrusion technique... plus the possibility of uneven spoke tensioning in an attempt to correct truing problems.

2... none... further failures are coming soon

3... they already did.

The rim is dead. If it's not wobbling now, it will soon as the gap gets bigger and bigger. maddog already explained the causes.

Rim's dead,stop riding it. You got 12k miles out of it,say thank you,it did its job. As to why it failed,things get old and break. Hell,12k on that speaks well of it.

yikes - its only a matter of time before that whole section around the eyelet comes away - you don’t want to be on the bike when it happens. Time for a new rim/wheel

Thanks for the responses - they confirmed everything that I feared.

I went ahead and ordered the exact same pair of wheels from Amazon. The new pair of wheels, with the Shimano freewheel and shipping included, was $99. Cost of doing business - a drop in the bucket.

Just MHO, but a rim should last a multiple of 12,000 miles. It looks like there's plenty of material left on the sidewalls in the picture, so I don't think it was worn down by heavy braking.

Again IMHO, I would not buy the same POS again.

I agree. Wheels are a safety issue. You could die. Don't skimp here.

Willy nilly tightening of spokes will probably do that too. Sometimes it's not the loose spoke that needs to be tightened. Sometimes the tight spokes need to be loosened.

I'd trash that rim.

Why did you do that?

Under the old adage: what's worth doing once, is worth doing again.
Or, you get what you pay for. Personally, I buy the best wheels possible, even on my beater bike.

Buy cheap, buy twice

Literally in this case.

Going on thrice, if #2 is as good as #1 was.

The cause is stupid design to accommodate STUPID eyelets. A square section rim?? LOL
BF needs a comedy forum for these asploding rim threads.
My oldest Velocity Dyad 700c has 32,000 miles including 8,100 with the SA dyno drum brake on the 120 lb tour bike.
Looks as good as new. The nipples settle into the thicker rim alu, that's what makes it solid.

What caused the damage? Any of a number of things. Spokes that are too tight can cause pull through. But spokes that are too loose can also cause cracking and pull through. Too tight is mostly self explanatory. If the spoke is too loose, the spoke goes through a loosening and tightening cycle that works aluminum. Aluminum doesn’t work very well and will eventually crack. Think a pop can that you flatten and bend back and forth repeatedly or a piece of aluminum foil you try to straighten out. Further down on the list is impact although that is way further down on the list and is somewhat related to the loosening/tightening cycle.

How much life left? None. Zilch. Zero. Bupkis. Get some butter and marmalade because it is toast.

Will a double wall make a difference? That is a double wall rim. A better quality double wall rim and, perhaps, double butted (or triple butted) spokes will make a difference, although 12,000 miles isn’t too bad for generic wheels.

In no particular order:

Reason #1 - Convenience. When you need a part ASAP to get to work, having an existing Amazon order that you know will drop in and fit without so much as having to adjust your brakes is a big plus.

Reason #2 - Quality. The wheel is a 26" mountain bike wheel. Serious riders don't hardly ride these anymore - they are typically found on toy store level bikes. Quality offerings from legit brands are far and few between. I knew the product I ordered had a certain level of quality - certainly better than the non-sealed single wall OEM wheels I replaced with my first purchase.

Reason #3 - Continuity. I always keep parts the same when possible. For example, the front wheel of this order can mount with a snow tire for when I need a change on a snowy day, or a regular tire for when I might have to leave for work but find the front tire flat. If the front rim cracks, I'll have an instant replacement. If the rear rim cracks again, I'll have a replacement if I take the front apart. Same with spokes and hubs and such.

Reason #4 - Value. I have no idea how they sell two wheels, complete with shipping, skewers, and a brand name freewheel, at the same price as two years ago - $99.

Reason #5 - Abuse. The bike is a commuter and an old 3x6 speed beater with a milk crate on the back, and it takes a beating. All kinds of roads and weather - 34 miles, 5 days a week. Putting nice anything on it wouldn't make a lot of sense, so I don't.

That rim practically exploded after very little time. Now you have three of them, but only one wheelset and you spent $198 total. Not $99.

I have inexpensive wheels that are 40 years old.

Conveinece, I can go down to my local shop and boom wheel in my hand and I can even have them put tires and cassettes on it,

So all the people riding 26" are joke riders? I know plenty of people who run 26 and I know there is still plenty of quality parts or rims to build a quality wheel with a ton of different hubs of quality. Also plenty of decent tires still out there. People act like it just magically died but when you have plenty of options out there I would hardly call it dead or a joke.

To sell a wheel set at $99 probably means. a lot of ethical concerns and quality concerns as well.

If I am abusing a bike, I should probably learn how to ride and take care of my things. Quality parts aren't a bad thing for commuting because in the end if you are relying on the bike to get to work you want something durable and reliable. However I wouldn't run a 3x6 these days for commuting but that is me I find corncobs to be to small of a ratio and the bigger stuff has too much space in between so I feel like I have missing gears. I have a 2x6 bike and it is fun bike to look at but my modern bikes are way better to ride including a nice 1x9 parts bike.

Might get luckier this time

not sure value = low price though

Double wall makes zero difference UNLESS spoke is tied into both walls, i.e., double eyelet/socket rims, those wear like iron, especially in fatigue. That rim is toast, due to the sidewall crack. One rim I had, crack at only the spoke hole, I fabricated a socket/thimble from copper to tie spoke into the inner wall, I put thousands of miles on that rim and it's still in storage, I was using it to keep wear off my more premium rims that I want good for a long tour.

Maybe it speaks well of a super-low price point wheel, but I would be really frustrated if my current wheels lasted only 12K miles. Velocity A23 rims spoked 32. 98K miles under my 175 lbs. as of today.

Time to call... Powdered Toast Man!

https://cimg2.ibsrv.net/gimg/bikefor...140a1271d.jpeg

Don't Risk Your Bum Riding This Wheel!