Broken spokes. 27.5" Giant alloy wheels.- Mtbr.com
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  1. #1
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    Broken spokes. 27.5" Giant alloy wheels.

    I KNOW this question has been asked and answered (perhaps many times), but my Google-fu is terrible on this site.

    My son has a Giant ATX. Loves it, rides the heck out of it, and won't even let me do a fork upgrade to it.
    He came home from trail yesterday after two spokes (right next to each other) snapped. We dropped wheel off at shop and the guy said "we can try to fix it, but with snapped spokes the wheel may be done/impossible to get perfectly true".

    Before I start shopping for a replacement bike (this one has seen enough use that I'm not going to throw any money at it), are these rims really that fragile that two snapped spokes will make the rim irreparably out of true? My son does wheelies every chance he gets, so I understand the stress on those spokes, but still...

  2. #2
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    The question is: why did the spokes break in the first place? did they break at the bends near the hub, in the middle, or the ends near the spoke nipples?

    you misunderstood what the bike mechanic was saying (or at least the most rational interpretation of it). the snapped spokes are not the issue. the wheel might not be out of true because of the snapped spokes. the spokes might have snapped because the rim is actually bent.

    if the rim is truly bent, replacing the spokes will only be a temporary fix. to get a bent rim true, they will need to put excessive tension on just a few spokes, and those spokes will eventually break again and again.

    I've built dozens and dozens of new bikes out of boxes, mostly entry-level bikes in the $500-1000 range. almost NONE of those bikes came with wheels that could be sent right out the door without some tweaking. I would inflate the tires, de-stress the spokes by applying force by hand to different parts of the wheel, put them each in the stand to adjust tension, de-stress again, true, then install the wheels and ride the bike. then check true again. if the bike came out of the box and was ridden without being tested and fine-tuned in this way, there's a good chance that the wheels were not as strong as they could be. they were probably strong, just not maximally so.

    you can get some more life out of a rim by forcefully bending it back. this is a temporary fix and usually best left for emergency repairs after taco-ing a wheel during a ride to get it straight enough to finish the ride and not drag the bike back or wait for a bail-out. if you can find the bent spot and wedge the rim between two rigid objects (upright rails on a handrail, two closely-spaced tree branches, etc), you can use the rim as a lever and bend it back into something that more closely resembles "true". if this results in close to even spoke tension all the way around, it was successful.

    this is a good chance for your son to learn a hard lesson: nothing lasts forever, but just about everything is repairable. sometimes repairing or replacing part of something makes it better and more unique than the original. bikes are meant to be ridden, used, repaired, maintained, and sometimes replaced.

  3. #3
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    A lot of info, so I'll answer each paragraph's question if that's OK.

    The question is: why did the spokes break in the first place? did they break at the bends near the hub, in the middle, or the ends near the spoke nipples?
    They broke VERY close to the nipples at the rim.

    you misunderstood what the bike mechanic was saying (or at least the most rational interpretation of it). the snapped spokes are not the issue. the wheel might not be out of true because of the snapped spokes. the spokes might have snapped because the rim is actually bent.
    We put new brake pads in a few days ago. The wheel has never been trued despite the miles on the bike, and was still very straight at that time (when we do a repair or changes, we give all components a "once over" while it's on the stand. The mechanic mentioned the possibility of a toasted rim without even looking at it (it was on floor in front of their counter).

    if the rim is truly bent, replacing the spokes will only be a temporary fix. to get a bent rim true, they will need to put excessive tension on just a few spokes, and those spokes will eventually break again and again.


    I've built dozens and dozens of new bikes out of boxes, mostly entry-level bikes in the $500-1000 range. almost NONE of those bikes came with wheels that could be sent right out the door without some tweaking. I would inflate the tires, de-stress the spokes by applying force by hand to different parts of the wheel, put them each in the stand to adjust tension, de-stress again, true, then install the wheels and ride the bike. then check true again. if the bike came out of the box and was ridden without being tested and fine-tuned in this way, there's a good chance that the wheels were not as strong as they could be. they were probably strong, just not maximally so.
    The store we bought it from does that on new bikes, but I have no guarantee they did it on THIS one


    you can get some more life out of a rim by forcefully bending it back. this is a temporary fix and usually best left for emergency repairs after taco-ing a wheel during a ride to get it straight enough to finish the ride and not drag the bike back or wait for a bail-out. if you can find the bent spot and wedge the rim between two rigid objects (upright rails on a handrail, two closely-spaced tree branches, etc), you can use the rim as a lever and bend it back into something that more closely resembles "true". if this results in close to even spoke tension all the way around, it was successfull
    ‚ÄčNo idea if the rim was out of true (thought I'm sure it was with the spokes gone), but it definitely was not visibly bent or deformed.


    this is a good chance for your son to learn a hard lesson: nothing lasts forever, but just about everything is repairable. sometimes repairing or replacing part of something makes it better and more unique than the original. bikes are meant to be ridden, used, repaired, maintained, and sometimes replaced.
    He already gets it, thankfully.
    A father-son project a few years ago was fully rebuilding and upgrading my 1969 Rupp Roadster. This year, we set up the secondary clutch to double the top speed. LOTS of repairs and handiwork. He has also done many repairs on older bikes along the way.

  4. #4
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    A wheel can go pretty far out of true with only one broken spoke, even more with 2 missing spokes. Usually they can be brought back to true after replacing them no problem but as Mack mentioned if the spokes broke due to a mishap of some sort and the rim is bent then the wheel is mostly doomed.

    The mechanic that looked at your wheel could obviously see more than we can here but for me it's often hard to determine a bent rim from a straight one until I replace the spoke and see how the tensions work out.
    I brake for stinkbugs

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