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25 votes

Is this rim still safe to use?

Sorry, those rims are trash (or wall art). I'd chase down the seller and demand your money back, and report them on whatever sites they were advertising on for selling items in a known dangerous state....
Argenti Apparatus's user avatar
21 votes
Accepted

Can this rear wheel be straightened or does it need to be replaced?

That rim is dead. You need to replace the rim at least. Being Aluminium it won't straighten, it will crack if you un-bend it. If you choose to continue riding it then you may get more punctures, ...
Criggie's user avatar
  • 127k
18 votes
Accepted

Cracked seat post

That seat post is made of carbon fiber tube and metal seat mount that plugs into it. The carbon tube is about to split and the inner part you see is the metal plug. It should be replaced immediately ...
ojs's user avatar
  • 22.2k
15 votes
Accepted

Rim cracks on spoke adjustment holes, how much should I panic?

To me, it looks like whoever (or whatever, as it was likely machine built) used the wrong size tooling to hold and screw the spoke nipples as the wheel was built. Not a rim manufacturing defect but a ...
RoboKaren's user avatar
  • 29.3k
14 votes

Frame dropout cracked, what can I do? (Allied Alfa Disc / carbon)

A crack, unfortunately, is a crack. That’s dangerous no matter what the material. You could contact Allied to see if you have any options in terms of warranty. However, if you didn’t secure the bike ...
Weiwen Ng's user avatar
  • 32.8k
12 votes

Should I ask for my money back - crack in Titanium frame

As you're in the UK, the Consumer Rights Act applies. It would seem that a £5,500 bike that lasts less than two years isn't of "satisfactory quality", but I would be surprised if the shop simply gave ...
srank's user avatar
  • 1,195
12 votes

Scratch or damage on carbon frame

That's just a light scratch. No issues. if you are worried that the carbon-fiber composite has been damaged by an impact or scratch, the abrasion is far too shallow for that. It has not even ...
Argenti Apparatus's user avatar
12 votes

Is it safe to ride on cracked carbon rims (Zipp 404 Firecrest 2010 edition)?

This doesn’t look like a simple scratch from grazing the side of the pothole. It almost looks like it buckled or severely deformed and now you have loose/delaminated fibers sticking out. Even if the ...
Michael's user avatar
  • 28.3k
12 votes

Can I trust my bike’s frame after I was hit by a car if there's no visible cracking?

Ideally, you should find someone who repairs carbon composites and who has ultrasound imaging equipment. They can detect delaminations (i.e. invisible fractures under the surface of the carbon) that ...
Weiwen Ng's user avatar
  • 32.8k
11 votes
Accepted

Cracked frame riding into the back of car, what's salvageable?

I've worked on a couple bikes that have had frontal impacts. Check the underside of the downtube for any abrasions or rubber marks. You might find the front tyre has touched the downtube in the ...
Criggie's user avatar
  • 127k
11 votes
Accepted

Crack/fissure in the headtube

Q: "[W]ould a competent welder be able to fix that crack[?]" No, that frame is done for. By attempting to weld such a crack, a welder would prove their incompetence. Even if you fix that crack you ...
gschenk's user avatar
  • 9,778
11 votes

Can this rear wheel be straightened or does it need to be replaced?

If its an aluminium rim it will most likly break when trying to bend out the dent. But if the dent isn't being bent back but just the wheel straightened I would be scared of the brakepad getting ...
Xenox's user avatar
  • 346
11 votes

Is it safe to ride on cracked carbon rims (Zipp 404 Firecrest 2010 edition)?

Sorry to hear about your damage. I don't think the crack is due to impact. Maybe, maybe not, but regardless of a reason the wheel has become damaged. On the two sided likeness of damage — things are ...
Grigory Rechistov's user avatar
11 votes

Is My Rim Cracked?

I will be the suspicious person, and I will wander a bit off-topic. No offense intended, I will only describe a worst-case scenario. I make one assumption: did you buy it second-hand because the price ...
EarlGrey's user avatar
  • 3,712
10 votes

Cracked chainstay weld -- now what?

Get in touch with Surly even if it out of warranty. The worst they can do is say no, and even if they won't fix it, they should be able to offer advise on the the best way to proceed. They live or die ...
mattnz's user avatar
  • 51.3k
10 votes

Crack in fork or just paint

I'm sorry to say that looks like a crack rather than a scratch. Bike looks quite new (I notice the dual pivot calipers), but I believe Trek's lifetime warranty covers CF frames and forks beyond 5 ...
Argenti Apparatus's user avatar
10 votes
Accepted

Crack in fork or just paint

On the surface it doesn't look good, but I wonder if there is a reinforcement wrap for the brake posts, with an unfinished edge). There are some informal ways to try and confirm whether the structural ...
Rider_X's user avatar
  • 30.7k
10 votes
Accepted

Repair frame with crack by seatpost clamp

Is it feasible to repair a crack in a frame around the seatpost clamp? feasible: 1. possible to do easily or conveniently. 2. likely; probable. It is possible to repair an aluminum frame. It is not ...
David D's user avatar
  • 22k
10 votes
Accepted

Does this carbon fork have a crack in it that would make you replace it?

What is visible in the photo is a paint scratch. Letting the bike simply fall over will not structurally damage carbon fiber composite. People seem to think CFC is fragile but it’s really quite robust....
Argenti Apparatus's user avatar
10 votes

Crack in aluminum seat lug on carbon-aluminum frame

The problem you're up against here is the cracked area of the seat lug is probably taking significant load in the original configuration of the seat cluster design. That implies you have to make it ...
Nathan Knutson's user avatar
10 votes
Accepted

Is it safe to ride a frame with a hairline crack in the head tube lug?

Answering your questions in the wrong order, it isn't a sign of "something more serious", it is though a serious defect in the frame. At best, the bottom cup will be a loose fit, and the ...
Noise's user avatar
  • 14.4k
9 votes

Big crack on my Schwalbe Marathon Plus tire

you can carefully prize the crack apart and see if it is just the rubber that is damaged or if it goes through to the casing. Your main focus should be where it extends to the sidewall as the tread ...
Andy P's user avatar
  • 18.3k
9 votes

Scratch or Crack?

That is bad news. It's too clean looking and parallel to the headtube top face to be at all likely to be a random scratch. It looks like a defect with the headtube. Even if it were a scratch, it would ...
Nathan Knutson's user avatar
8 votes
Accepted

Is this a cracked frame?

Yep, that looks like some pretty extensive cracking. I'm sure this is obvious to you, but do not ride this bike as the frame may fail catastrophically. Update: Sorry your three year old frame ...
Argenti Apparatus's user avatar
8 votes
Accepted

Cracks on tire - still safe to ride?

The type of tire cracking that is most worrisome is when it's accompanied by bulging areas from the tube pressure. This implies damage to the casing, which in turn implies a tire that might very ...
Nathan Knutson's user avatar
8 votes

Scratch or damage on carbon frame

If you saw my Stevens Team Carbon cyclocross frame you'd feel much better.
bradly's user avatar
  • 1,475
8 votes

Frame dropout cracked, what can I do? (Allied Alfa Disc / carbon)

Yes it's dangerous. Contact Allied.
Adam Rice's user avatar
  • 30.1k
8 votes

Is this crack in a used bike's head tube safe enough to purchase the bike?

That spot on the headset is not normally loaded during steady-state riding, because the weight is normally on the opposite side of that bearing. Option 1 The prime suspect for this is a frontal impact ...
Criggie's user avatar
  • 127k
8 votes

Can I trust my bike’s frame after I was hit by a car if there's no visible cracking?

No one can say for certain the frame is now safe to ride without ultrasound imaging. Bike frames are designed to handle normal use forces of riding and maybe a crash where the rider falls off. They ...
mattnz's user avatar
  • 51.3k
8 votes

Can I trust my bike’s frame after I was hit by a car if there's no visible cracking?

Let's get this out of the way: IMO any carbon-fiber bike that's actually been run over by a car would probably require more testing than it's worth to make sure nothing is cracked - think "close-...
Andrew Henle's user avatar
  • 10.7k

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