Why does my sons re...
 

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[Closed] Why does my sons rear wheel fall off

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So the last 2 or 3 times my 11yr old son has been lifting his voodoo bike into the shed after a spin the rear wheel has dropped out. I have put it back on and re tightened it but today he took a header as it came off while riding outside the house.

Any suggestions as to cause? Its a 135mm qr and he is only riding about the street. I have put on an old Hope skewer for now to see if that stops it but he is a bit scared it will happen again and i cant see anything wrong.


 
Posted : 17/09/2019 6:04 pm
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Probably just a cheap shit qr, crank the hope one up tight, take it out for a spin and do some bunny hops. If it doesn't fall out, you've cracked it. Well hopefully not but you know what I mean.....

If that doesn't work try it with a shimano one.


 
Posted : 17/09/2019 6:10 pm
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I would probably just go straight for the Shimano one.

It is being used correctly, not just screwed up, isn't it?


 
Posted : 17/09/2019 6:13 pm
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My daughter's bike started doing this. QR is pretty sturdy and goes over-centre. Cannot figure it out.


 
Posted : 17/09/2019 6:16 pm
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I'm sure I've read other threads about this but can't remember the conclusion. I think it's not always the qr that can cause it from memory though. Can be a twist in the frame/drop out or something?


 
Posted : 17/09/2019 6:17 pm
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Is the axle protruding from the frame.

If the axle is misadjusted and the qr tightens against the end of the axle ....it's not clamping the frame.

It's reasonably common on bikes taken from boxes and badly assembled.


 
Posted : 17/09/2019 6:18 pm
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Yep tightened correctly (not screwed up). I tried an old shimano one first  but its a couple of mm too short for some reason, the hope one is a couple off mm longer (like the one on the bike) so fitted that. Had a spin (no bunny hop skills here but managed an endo or two😉) and it seems fine, but then again it did the last time too. If it is just the skewer is sh!t then i think i better swap out the front one too.


 
Posted : 17/09/2019 6:24 pm
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I am thinking it may be the hub, the nut that is meant to be serrated and grip the dropout looks like its made of cheese and has gone rather smooth, so may not be gripping when doing the skewer up. I will need to hunt down the old shimano hub i have god knows where, and swap this too i think.


 
Posted : 17/09/2019 6:32 pm
 ajaj
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Does your son have friends that enjoy opening and closing levers?


 
Posted : 17/09/2019 6:38 pm
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Like poopscoop I'm pretty certain this came up before on a voodoo.


 
Posted : 17/09/2019 7:50 pm
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Has your son been fiddling with it and not closed the lever properly?


 
Posted : 18/09/2019 10:49 am
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I would wager the bearings are locked up and the axle is undoing itself.

Are they loose bearings or cartridge?

I would service the hub to be sure.


 
Posted : 18/09/2019 12:25 pm
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Thanks for replies and thoughts. It was definitely not any friends (he was on his own) or him going at the skewer (i thought maybe his heel was hitting it but its not) and i had a look at the bearings when I changed the end nut over, its cup and cone and looks like new inside and running free from what i can see. Worrying that it seems to be common on voodoos, just glad it didnt happen belting down the trails as he got enough cuts/grazes coming of on the street. I will see if it happens again now i have changed the skewer and hub end bolts.


 
Posted : 18/09/2019 3:40 pm
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I had a similar problem, turned out to be the QR spring was getting caught in the hollow axle and giving a false tightness when doing it up.


 
Posted : 18/09/2019 3:44 pm
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^^^hmmm this might of been the issue, when i took the old skewer off the spring seemed caught up a wee bit .


 
Posted : 18/09/2019 4:07 pm
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Many years ago I had a similar problem on my Marin Quake. Turned out the gear hanger was steel and the knurled bits of the axle nut & QR wouldn't grip properly on it as it was too hard & smooth, so the axle kept slipping in the dropout.

IIRC I resolved it by attacking the hanger with a Dremel and carved some grooves in the hanger.


 
Posted : 18/09/2019 4:12 pm
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^^^ I was contemplating doing the same too. Cheers.


 
Posted : 18/09/2019 4:14 pm
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Just to add to the anecdata I had this happen on a voodoo bizango a few times.

No explanation offered, and I know how to correctly operate a QR, and checked it frequently after the first time.


 
Posted : 18/09/2019 4:42 pm
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According to the Worst bike “improvements” thread, you are simply imagining things.


 
Posted : 18/09/2019 6:43 pm

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