Author Topic: On a scale of 1 to dead, how dangerous is it to ride on a cracked bike rim?  (Read 4222 times)

Guses

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Commuting to work this morning, my back wheel was making this weird "tick-tick-tick" noise since about halfway. Upon closer inspection, I noticed an outward bulge in my rim with a small protrusion and a crack.

Looks like I will be needing a new set of rims.

Here is my question:   

How dangerous would it be to ride my bike home tonight? It is about 8 miles by the shortest route.

I am mostly climbing on the way home and I would be disconnecting the back brake and going slowly. If it gets too bad, I can always walk the rest of the way (like I did when my chain broke that one time).

driftwood

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My opinion:  I think the biggest risk is the potential for the rim to break and the subsequent fall to put you out into traffic in front of a vehicle.  I don't really know if your route has much traffic or not, or if you can stay on sidewalks where a broken rim would probably just end up in a spill.


Guses

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It is exclusively bike paths except for a couple of blocks to reach the path.


GuitarStv

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Once a crack gets to the side of the rim it's just a matter of time before the pressure from the wheel makes it burst . . . I've had a rear tire pop on me in traffic (after going over a particularly assholish nail), and it's more exciting than I would care to go through again.  If you're going to ride back home, be very very careful, go slow, and ride like it's about to fail (because it is).

Syonyk

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So... did you make it?

I'd have tried it if it was the rear wheel.  I probably wouldn't with the front.  Most rear wheel failures are easy enough to "ride it out" and come to a stop on.  Front wheel failures are radically less forgiving.

stripey

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I'd have tried it if it was the rear wheel.  I probably wouldn't with the front.  Most rear wheel failures are easy enough to "ride it out" and come to a stop on.  Front wheel failures are radically less forgiving.

That would have been my advice too.

Also, I got sucked in by the tread title! Scale of '1 to dead'

Guses

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I made it!!!!!

Looking at the rim, the splinter/crack appears to be longer. I probably won't ride on it again.

Any recommendations for replacement rims?

Would any 26 inch rim word or does it need to have the same number of holes or something?

CletusMcGee

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Any recommendations for replacement rims?

Would any 26 inch rim word or does it need to have the same number of holes or something?

You're going to want to take it to a bike shop.  Wheelbuilding is best left to the professionals and geeks like me who know what flange PCD, offset and ERD mean.  But yeah, if you have a 32 spoke hub, then you need a 32 spoke rim.  Hopefully the replacement rim will have the same ERD so that they can re-use your existing spokes.

Guses

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Any recommendations for replacement rims?

Would any 26 inch rim word or does it need to have the same number of holes or something?

You're going to want to take it to a bike shop.  Wheelbuilding is best left to the professionals and geeks like me who know what flange PCD, offset and ERD mean.  But yeah, if you have a 32 spoke hub, then you need a 32 spoke rim.  Hopefully the replacement rim will have the same ERD so that they can re-use your existing spokes.

I just checked rims and it looks like they are running about 30$+ spokes + installation.

How about just switching the entire wheelset? There is a 26 inch mtb for sale on my local BST for 20$. If I confirm that it uses a cassette system, I could just plop my own in there and just do a switch no?

Syonyk

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Yup. Assuming the dimensions are the same.

moustacheverte

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Re: On a scale of 1 to dead, how dangerous is it to ride on a cracked bike rim?
« Reply #10 on: December 06, 2015, 11:26:32 AM »
Maybe check if there is a community bike workshop where you live? I have 2 in my city and it's great, you can buy parts from them at cost, they also sell used/salvaged parts and you do the installation yourself. They have all the tools and guidance you need, you'll save big on labor and you'll learn how to fix your own bike.

In my city, used rims with spokes (may need to be trued) go for about 10$, gently used tires are free and a tube is 3$.

spokey doke

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Re: On a scale of 1 to dead, how dangerous is it to ride on a cracked bike rim?
« Reply #11 on: December 07, 2015, 07:46:56 AM »
shopping for a an entire used wheel is a possible option if you are in a decent sized town - lots of places have community bike shops that take in used bikes and parts and fix them up and resell them as a form of community support...bike shops might also have one that would work (but they will try to sell you a new wheel, and some factory built wheels might be less than paying to relace a new rim to your old hub).

give used wheels a spin test, not only to see how true they are, but feel the vibrations in the axle to see how smooth the bearings/cones/races are in the hub.