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About a month ago I bought a Giant contend AR 3, and have been quite satisfied with the purchase until about 3 days ago when the front wheel started to sound... bad... crackling/poping. From what I could tell, the bearing seemed to have gone bad. Took it to the dealer and he seemed to agree, though it's still in for repairs. It's very unlikely to be due to water entering, as the front usually don't get that dirty, and I just use soap and sponge.

Apart from a defect, the only thing that would come to mind is riding it too "rough". I'm not completely careless while riding, I try to dodge the bumps and podholes whenever I can... but you know, it does happen. If anything, it thought the rim would be the first to give up, but it's perfectly fine, straight no bends, as are the spokes. It doesn't "wobble" or feel loose while mounted either.

So, the TLDR; is this normal? Can the bearings go bad this fast, or does it just come down to lower quality parts? Would upgrading to better bearings help, or do I just need to take better care while out and about? This is my first "racing" bike, so I'm kinda uncertain on how frail these bikes are. Should note that I've clocked around 1500 km over the month I've had it, so it's been used quite a lot.

Cheers from a noob :D

Edit: Will give an update once the bike is back from the dealer. Haven't heard anything yet :(.

The bike is now fixed: Picked up the bike from the repair shop today. Apparently the hub wasn't tightened well enough during assembly, which had caused the bearings to misalign; from what I could understand it doesn't use cartridge bearings, and the bearings themselves were quite small.

He has re-greased the hub etc., and far as I can tell, everything is working a-ok again. No charge.

Thanks a lot for the support everyone :)

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    Now that the bike is fixed - pull the front wheel and make sure the hub is adjusted correctly. Pull the rear wheel and check it too - just in case.
    – David D
    Oct 4 at 16:34
  • Hey David :), will do that. He had looked at the rear wheel as well, as it was making a squeaking sound (didn't sound like anything alarming though).
    – Ills
    Oct 5 at 20:25

3 Answers 3

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It's not clear what the question is, but there are some things you should know. Hopefully this covers the information you were trying to seek.

  1. If the bearings were bad, then this is not normal. There are no realistic scenarios where you could ruin good bearings in 3 days. Never mind how cheap they are or how many potholes you hit.
  2. You can take the wheel out of the dropouts, and try turning the axle by hand. With new wheels, you will feel the bearings turning smoothly. If you feel roughness or grittiness, the bearings may be worn out - that is the steel balls and/or the races they turn on are pitted. Every mechanic will know how to do this test.
  3. It is possible that the bearings were defective from the factory. In particular, the holes the bearings sit in may not be round. That will compress the bearings at certain points in their rotation and cause damage to the balls and/or races. Or there's some other defect. If it were me, I would press for a warranty replacement of the wheel if this is the case. Assessing the tolerances of the bearing seats is probably not something that everyone knows how to do.
  4. Most wheels have cartridge bearings. The bearings plus races are supplied as complete units by third parties, and they're pressed into the hub. Most such hubs can't be adjusted, in that you can't make the bearings tighter or looser. See the link in my comments about preload. If they're cup and cone hubs, then these are adjusted for tightness, and some of them may come too tight from the factory. The store should probably have adjusted them.
  5. If the above case were correct, then upgrading the bearings would do nothing other than waste a nice bearing. If it were the bearing, then just replacing the bearing is acceptable. Bearings do wear, so if you keep this bike, the wheels should eventually need their bearings replaced. However, you might be able to upgrade with a used wheelset, or you may want to pay more for a new and upgraded one, or you may have a spare set of other OEM wheels from another bike.

I realize I am describing sensations and parts where you have no idea what they are or what they feel like. This is the sort of thing that you need to be shown in person. Your mechanic might do this if you ask nicely! Bicycles are complex objects, so there are a lot of parts involved and there is a learning curve if you want to maintain or understand them.

As noted in the comments, if the dealer agreed to replace the wheel under warranty, that seems 100% reasonable.

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    Over tightened bearing will fail prematurely, but probably not in in month...
    – mattnz
    Sep 29 at 4:00
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    Thanks for the reply Weiwen :). I did take the wheel off the bike and tried turning it by hand, no doubt the sound was coming from inside the hub. The dealer noted that it sounded quite bad when I did a demonstation. He also noted that it would likely be replaced under warranty, and that they'll most likely swap the entire wheel for a new.
    – Ills
    Sep 29 at 17:02
  • @mattnz - Hey :), I haven't tightened anything on the wheel myself. I assume the dealer does little other than installing it on the fork - and it certainly wasn't too tight when I took it off to check the bearings.
    – Ills
    Sep 29 at 17:43
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    If the hubs are cartridge bearing, then I believe over-tightening is usually not a thing. However, if they are cup and cone, then they could have been over-tightened (i.e. too much preload). I've heard that cup and cone hubs often come over-tightened from the factory.
    – Weiwen Ng
    Sep 29 at 19:45
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    @Ills - not you - I have had bikes delivered from shop with way overtightened bearings.
    – mattnz
    Sep 29 at 20:01
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TLDR: To me, this sounds like a clear warranty case.

I'm not even sure if intentional misuse like directing a jet washer directly at the hub could ruin bearings that quick if there wasn't an issue from factory or initial assembly.

1500 km are some distance but realistically, people take bikes out on ultra-cycling races and go for longer distances without cleaning and maintenance in one go, in many instances with full days in the rain and over gravel/dirt tracks (see this year's Transcontinental Race edition).

Bearings should be able to take bumps, road and gravel bikes don't have any suspension and the latter take even more abuse on gravel tracks, just hitting a pothole that doesn't do any other damage isn't very likely to kill bearings that quick.

Unless you have done some service/adjustments to the hub on your own, I can't see any reason how this could go wrong so quickly from the user perspective.

I'd make sure that this is covered by warranty and the dealer doesn't charge you for service/bearings. My first road bike had a noisy rear hub after a few months and my dealer swapped it for free without any discussion (covered by the manufacturer's warranty conditions).

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    Thanks for the reply DoNut :) Being new to the sport, I don't really have a point of reference nor know how easy these bikes damage - so it's good to hear that it's unlikely to have been damaged due to misuse. The bumps certainly hit hard, but yes, rim and spokes are fine. I haven't serviced/adjusted anything on the wheel. Been driving once in the rain, and all cleaning has been done with a bucket of water and sponge in hand. I considered replacing the bearings myself, but also assumed it would be fixed under warranty.
    – Ills
    Sep 29 at 17:26
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    @Ills That absolutely sounds like something is wrong and you're not to blame. Few bumps and a normal wash certainly don't ruin bearings. Wouldn't touch it and check with your shop, I'd be surprised if they don't fix it hassle-free. Also good to know what was actually wrong in the first place.
    – DoNuT
    Sep 29 at 17:39
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Certainly not normal. Most likely installation error or manufacturing defect.

I’ve never heard of bearings failing because somebody rides “too rough”. Usually the wheel’s spokes fail long before anything else.

The sealed cartridge bearings in wheel hubs should usually last >10Mm unless you are really heavy or seriously abusing them (e.g. aiming a pressure washer right at the bearings).

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  • Thanks for the reply Michael :) The wheel seemed to be installed correctly. The release was firmly tightened, but not excessively. No pressure cleaning has been done, I barely have to clean it given how little dirt that gathered.
    – Ills
    Sep 29 at 17:39

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