How did I bend my wheel in half!

General cycling advice ( NOT technical ! )
gbnz
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How did I bend my wheel in half!

Postby gbnz » 18 Oct 2019, 8:42pm

Hmm.......any thoughts? Further to an accident last weekend my front wheel is bent in two. If not in half by ay least 40 degrees! I can't figure it out! It's the front wheel on the bike, a moderate strength exal rim, 32 spoked, home built, five years use but minimal wear (NB. despite a good mileage).

1. Has the wheel dropped into a grated manhole and effectively bent in two as I've toppled over? (NB. There are grated manholes on the road section in question)
2. Has the construction itself failed? I put it together as a temporary wheel five years ago, a bit concerned that a good few spokes were differing lengths. But following five years use it remained in near perfect true, spokes all tensioned, perfectly acceptable wear to the rim, no sign of issues developing (NB. I check as a matter of routine)
3. Has a vehicle run over it and bent it out of shape?

Can't figure it out (NB. I'll have had a seizure resulting in the accident, but I can't see merely toppling off the bike resulting in this damage :? )

Brucey
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Re: How did I bend my wheel in half!

Postby Brucey » 18 Oct 2019, 9:56pm

if you turn the steering sideways violently/suddenly enough, the front wheel will just fold over. Wheels are not that strong laterally; I have folded them over in exactly that way (e.g. swerving to avoid someone who stepped out from between parked cars). In Richard's bicycle book I think it describes the result as being like "the front wheel melts into the tarmac" or similar. Maybe something like that is what happened?

cheers
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~~~~~~~~~~~~~~~~~~~~~~Brucey~~~~~~~~~~~~~~~~~~~~~~~~

PH
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Re: How did I bend my wheel in half!

Postby PH » 19 Oct 2019, 7:59am

When I had a handlebar break, the wheel turned sharply and did just that.

iandriver
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Re: How did I bend my wheel in half!

Postby iandriver » 19 Oct 2019, 9:14am

This photo of it happening to Cav shows it rather well.
https://www.reddit.com/r/peloton/commen ... does_best/
Supporter of the A10 corridor cycling campaign serving Royston to Cambridge http://a10corridorcycle.com. Never knew gardening secateurs were an essential part of the on bike tool kit until I took up campaigning.....

gbnz
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Re: How did I bend my wheel in half!

Postby gbnz » 19 Oct 2019, 9:22am

Thanks to both, have to admit the concept that a wheel could simply "fold" isn't one I'd have thought of. But it's clearly happened to others, so clearly it can! On a postive note, a passing delivery driver picked the bike up, returned it home and took the care to carefully tuck it behind the wheelie bins.

A fantastic sight to see on arriving home at 04.30am, 40 odd hours post accident :D

mercalia
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Re: How did I bend my wheel in half!

Postby mercalia » 19 Oct 2019, 11:49am

half the spokes break at the same time? does that ever happen. maybe a few then the stress does the rest?

pwa
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Re: How did I bend my wheel in half!

Postby pwa » 19 Oct 2019, 7:03pm

Isn't what happened to that wheel sometimes called "crisping", in the sense that the wheel ends up bent like a crisp? I've done it with a rear wheel when I skidded in a crash. Many years ago.

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RickH
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Re: How did I bend my wheel in half!

Postby RickH » 19 Oct 2019, 8:04pm

pwa wrote:Isn't what happened to that wheel sometimes called "crisping", in the sense that the wheel ends up bent like a crisp? I've done it with a rear wheel when I skidded in a crash. Many years ago.

I think what you call "crisping", & I have generally heard called "pringling", is a somewhat different phenomenon where the rim twists into another fairly stable state (which it sometimes possible to get the wheel to spring back to something like true from).

I've seen it happen in a cyclocross race where a rider trying to regain control has turned the bars too far & bent the wheel ending up with 2 semicircles of wheel more-or-less at right angles to each other, but the 2 halves each still looking reasonably true.

pwa
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Re: How did I bend my wheel in half!

Postby pwa » 19 Oct 2019, 8:10pm

RickH wrote:
pwa wrote:Isn't what happened to that wheel sometimes called "crisping", in the sense that the wheel ends up bent like a crisp? I've done it with a rear wheel when I skidded in a crash. Many years ago.

I think what you call "crisping", & I have generally heard called "pringling", is a somewhat different phenomenon where the rim twists into another fairly stable state (which it sometimes possible to get the wheel to spring back to something like true from).

I've seen it happen in a cyclocross race where a rider trying to regain control has turned the bars too far & bent the wheel ending up with 2 semicircles of wheel more-or-less at right angles to each other, but the 2 halves each still looking reasonably true.

Pringles didn't exist in about 1990 when I did it to a wheel and told my better half that I needed a new wheel because I had "crisped" one. Whatever it was called, it wasn't rectifiable with a spoke key. Definitely cause by dragging sideways a loaded wheel that wasn't designed for that.

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RickH
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Re: How did I bend my wheel in half!

Postby RickH » 19 Oct 2019, 8:19pm

pwa wrote:Pringles didn't exist in about 1990 when I did it to a wheel and told my better half that I needed a new wheel because I had "crisped" one. Whatever it was called, it wasn't rectifiable with a spoke key. Definitely cause by dragging sideways a loaded wheel that wasn't designed for that.

I've never had cause to try it but the situation I'm thinking of is where the distortion is symmetrical - diametrically opposite sides go a bit one way & the opposite sides in between go the other way. Rather than use a spoke key, the roadside repair is to whack one side of the wheel (with the tyre still on) on the ground to try to get it to spring back into shape (or near enough to ride to somewhere where a more permanent repair can be done).

pwa
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Re: How did I bend my wheel in half!

Postby pwa » 19 Oct 2019, 8:49pm

RickH wrote:
pwa wrote:Pringles didn't exist in about 1990 when I did it to a wheel and told my better half that I needed a new wheel because I had "crisped" one. Whatever it was called, it wasn't rectifiable with a spoke key. Definitely cause by dragging sideways a loaded wheel that wasn't designed for that.

I've never had cause to try it but the situation I'm thinking of is where the distortion is symmetrical - diametrically opposite sides go a bit one way & the opposite sides in between go the other way. Rather than use a spoke key, the roadside repair is to whack one side of the wheel (with the tyre still on) on the ground to try to get it to spring back into shape (or near enough to ride to somewhere where a more permanent repair can be done).

I almost want that phenomenon to happen so I can give that "fix" a try.

Jamesh
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Re: How did I bend my wheel in half!

Postby Jamesh » 19 Oct 2019, 11:08pm

:( :( :( :(
pwa wrote:
RickH wrote:
pwa wrote:Pringles didn't exist in about 1990 when I did it to a wheel and told my better half that I needed a new wheel because I had "crisped" one. Whatever it was called, it wasn't rectifiable with a spoke key. Definitely cause by dragging sideways a loaded wheel that wasn't designed for that.

I've never had cause to try it but the situation I'm thinking of is where the distortion is symmetrical - diametrically opposite sides go a bit one way & the opposite sides in between go the other way. Rather than use a spoke key, the roadside repair is to whack one side of the wheel (with the tyre still on) on the ground to try to get it to spring back into shape (or near enough to ride to somewhere where a more permanent repair can be done).

I almost want that phenomenon to happen so I can give that "fix" a try.

Think I would first of all remove my front teeth from the tarmac before trying! :( :(

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RickH
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Re: How did I bend my wheel in half!

Postby RickH » 20 Oct 2019, 1:00am

pwa wrote:I almost want that phenomenon to happen so I can give that "fix" a try.

I found a short video on YouTube demonstrating the technique! :shock:


Darkman
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Re: How did I bend my wheel in half!

Postby Darkman » 23 Oct 2019, 12:35pm

"and in my next tutorial video, I'll be showing you how to dig up and replace cracked paving slabs" :mrgreen:

rjb
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Re: How did I bend my wheel in half!

Postby rjb » 23 Oct 2019, 12:59pm

In an idle moment whilst channel hopping i came across the red bull soapbox challenge on the TV. It spiked my interest as I have a 6 year old grandson and was thinking about building one with him. Several of those soapboxes had wheels fold up on them during the run and it surprised me to see that it didn't take much to do it. It's broadcast on Dave at 6pm on Sundays. :wink:
Or look on u tube.
At the last count:- Focus Variado, Peugeot 531 pro, Dawes Discovery Tandem, Dawes Kingpin, Raleigh 20, Falcon K2 MTB dropped bar tourer, Longstaff trike conversion on a Falcon corsa. :D