Spoke broken by chain - autopsy and plan of action

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doffcocker
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Spoke broken by chain - autopsy and plan of action

Post by doffcocker »

Less than a month ago I invested in a new Shimano wheel (see link), and had been over the moon with it until last night when true to form my luck ran out and my chain, shifting from 2nd to 1st gear, jumped right over the largest ring and into the spokes. As I just about manage to release it from behind the cassette, I realise that in jamming itself there it had caused a spoke to snap at the hub.

https://www.amazon.co.uk/gp/product/B07 ... UTF8&psc=1

On a more positive note, this happens the night before my 30 day guarantee expires, and Amazon are sending me a replacement. But it could be up to a month before that arrives, so what are my options in the meantime?

Should it be safe enough to get by if I just remove the broken spoke and crack on?
Instead of buying a packet of replacement spokes, I still have my old wheel, is it a done thing at all to remove spokes from an old wheel to be used as replacements, short term or otherwise?

Also, going forward, do I need to review the indexing of my gears? Generally speaking they have been working like a dream this last month in every way, there has only been a few occasions where this has happened. The chain sort of goes flying into the spokes - not from the largest cog - but from 2nd and maybe 3rd, mainly when I'm climbing the gears quite rapidly and maybe putting too much force into the pedals?
Darkman
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Re: Spoke broken by chain - autopsy and plan of action

Post by Darkman »

Sounds like your gears just aren't set up right, otherwise the low limit screw would stop this happening regardless of how far off your indexing is.

I'm surprised Amazon are sending a replacement, given that your gear setup is likely what caused the damage rather than the wheel itself.

I have no idea on spoke etiquette. I'm the happy owner of a dork disc (which saved me from a similar fate after I bent the mech hangar in an earlier fall).
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LinusR
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Re: Spoke broken by chain - autopsy and plan of action

Post by LinusR »

doffcocker wrote: 27 Sep 2021, 1:19pm

Also, going forward, do I need to review the indexing of my gears? Generally speaking they have been working like a dream this last month in every way, there has only been a few occasions where this has happened. The chain sort of goes flying into the spokes - not from the largest cog - but from 2nd and maybe 3rd, mainly when I'm climbing the gears quite rapidly and maybe putting too much force into the pedals?
Yes. You should turn clockwise the "L" limit screw (low) on the mech so that the chain does not overshoot the largest cog. It is best to err on the side of caution and adjust it so that the chain will only just shift to the largest cog. Turn it clockwise a 1/4 turn at a time until it won't shift from 2nd to 1st. Then turn it counterclockwise a 1/8 of a turn at a time until it shifts properly.
richardfm
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Re: Spoke broken by chain - autopsy and plan of action

Post by richardfm »

If the spokes on the old wheel are the same length as the new, give or take a mm or two then it should be ok to reuse one.
Richard M
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doffcocker
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Re: Spoke broken by chain - autopsy and plan of action

Post by doffcocker »

Darkman wrote: 27 Sep 2021, 1:31pm I'm surprised Amazon are sending a replacement, given that your gear setup is likely what caused the damage rather than the wheel itself.
Obviously I know it's not Amazon's fault, but they are incredibly good when it comes to returns, or at least they are with me, probably because of the ungodly amount of money they have gotten out of me over the years.
Valbrona
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Re: Spoke broken by chain - autopsy and plan of action

Post by Valbrona »

Essentially, your new wheel has not placed the cassette in exactly the same place as the old.
I should coco.
Jdsk
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Re: Spoke broken by chain - autopsy and plan of action

Post by Jdsk »

As above: adjust the limit screws.

Jonathan
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tykeboy2003
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Re: Spoke broken by chain - autopsy and plan of action

Post by tykeboy2003 »

Properly set the limit screw as others have said.

Buy a few spare spokes from you LBS and replace the broken spoke. In my experience, it's always the drive-side that loses the occasional spoke probably because of the wheel being slightly dished to accommodate the freewheel/cassette. I wouldn't ride it with a missing spoke for too long as it will increase the likelyhood of losing another one.
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simonineaston
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Re: Spoke broken by chain - autopsy and plan of action

Post by simonineaston »

The redoubtable Calvin Jones treats us to 15 minutes of excellent advice on adjusting rear mech.s here. Be sure to watch as it's invaluable.
(rides: Brompton nano & ever-changing Moultons)
simonhill
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Re: Spoke broken by chain - autopsy and plan of action

Post by simonhill »

Darkman wrote: 27 Sep 2021, 1:31pm
I'm the happy owner of a dork disc (which saved me from a similar fate after I bent the mech hangar in an earlier fall).
Dork disc? Is that the plastic disc that sits between cog and spoke? Used to be essential on very early MTBs. Sadly (?) rarely seen nowadays. I do still use a gear guard (bent bit of wire protecting the rear mech), mainly for when bike is in transit.
Manc33
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Re: Spoke broken by chain - autopsy and plan of action

Post by Manc33 »

doffcocker wrote: 27 Sep 2021, 1:19pmDo I need to review the indexing of my gears?
Not the indexing, the L limit screw.
doffcocker wrote: 27 Sep 2021, 1:19pmGenerally speaking they have been working like a dream this last month in every way, there has only been a few occasions where this has happened.
It shouldn't ever happen. Screw the L limit screw in half a turn and see if it still shifts to the biggest sprocket.
When two cyclists get married, they should throw anodized cable crimps instead of confetti.
Cowsham
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Re: Spoke broken by chain - autopsy and plan of action

Post by Cowsham »

Last night while watching the moto 3 race I noticed some of the 250/300cc motorcycles sporting a solid or covered rear wheel like velodrome bikes.

Image

Don't know if that's for aerodynamics given the lower power available but it looks great. Would stop the chain getting jammed and spitting the pilot off too.
Don't let your children watch television until they know how to read or all they'll know how to do is curse, fight and breed.
Darkman
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Re: Spoke broken by chain - autopsy and plan of action

Post by Darkman »

simonhill wrote: 27 Sep 2021, 6:07pm
Darkman wrote: 27 Sep 2021, 1:31pm
I'm the happy owner of a dork disc (which saved me from a similar fate after I bent the mech hangar in an earlier fall).
Dork disc? Is that the plastic disc that sits between cog and spoke? Used to be essential on very early MTBs. Sadly (?) rarely seen nowadays. I do still use a gear guard (bent bit of wire protecting the rear mech), mainly for when bike is in transit.
Yeah, that. They do still come as standard on many bikes but people usually remove them because they're not deemed "cool", hence the name. In my view it's there for a purpose, as is the bell. Sporting bright yellow lycra, usually, it should be apparent that I don't care what I look like. :mrgreen:
Jdsk
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Re: Spoke broken by chain - autopsy and plan of action

Post by Jdsk »

Cowsham wrote: 28 Sep 2021, 7:52am Last night while watching the moto 3 race I noticed some of the 250/300cc motorcycles sporting a solid or covered rear wheel like velodrome bikes.

Don't know if that's for aerodynamics given the lower power available but it looks great. Would stop the chain getting jammed and spitting the pilot off too.
And makes riding in variable side winds a completely different experience...

: - )

Jonathan
Cowsham
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Re: Spoke broken by chain - autopsy and plan of action

Post by Cowsham »

Jdsk wrote: 28 Sep 2021, 10:11am
Cowsham wrote: 28 Sep 2021, 7:52am Last night while watching the moto 3 race I noticed some of the 250/300cc motorcycles sporting a solid or covered rear wheel like velodrome bikes.

Don't know if that's for aerodynamics given the lower power available but it looks great. Would stop the chain getting jammed and spitting the pilot off too.
And makes riding in variable side winds a completely different experience...

: - )

Jonathan
Yeah -- tt windy corner comes to mind -- wonder how that would go?
Don't let your children watch television until they know how to read or all they'll know how to do is curse, fight and breed.
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