Is my chain too lon...
 

[Closed] Is my chain too long ?

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I changed from 11-42 on a 32t to a 10-42 on a 30t (oval).

I have lost 3 teeth so the chain is never taut even in this max configuration.

Seems to work OK but perhaps a little noisier than before on the 42t. Would it be because the chain is too long ? Or due to the oval ring ? Or neither ? Or both ?

I have a SRAM powerlink so do I simply open it with thin nose plier and remove 2 links (the minimum presumably) ?

Thanks for any guidance.

[url= https://image.ibb.co/nNsxpF/chain.jp g" target="_blank">https://image.ibb.co/nNsxpF/chain.jp g"/> [/img][/url]


 
Posted : 01/09/2017 4:42 pm
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A 30t oval at its maximum eccentricity will be the same as a 32t, your rear is still a 42t so it should remain the same. Ensure your checking with the oval ring at its greatest radius.


 
Posted : 01/09/2017 4:46 pm
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I'd say so looking at that, is it really slack in the 10? If not then I'd just leave it.


 
Posted : 01/09/2017 4:47 pm
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A 30t oval at its maximum eccentricity will be the same as a 32t

You do realise the chain is wrapped around half the ring so a 30 is two teeth less than a 32 regardless of roundness?


 
Posted : 01/09/2017 4:50 pm
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How does the mech look on the smallest cog?


 
Posted : 01/09/2017 4:53 pm
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I found the oval nw superstar chainring I had was quite a bit noisier than the round nw race face chainring I had. After a month or so of riding the oval quietened down a bit - although in really sloppy mud I found it dropped the chain far easier than the round one.

I'm back to a round chainring now and don't plan to swap back to an oval.


 
Posted : 01/09/2017 4:53 pm
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I always thought the mech should be in that sort of position, or maybe a tad back when in the highest gear?


 
Posted : 01/09/2017 4:58 pm
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Posted : 01/09/2017 5:04 pm
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Thx everyone - here is the chain when in the 10t:

[url= http://image.ibb.co/ggB1Ya/chain2.jp g" target="_blank">http://image.ibb.co/ggB1Ya/chain2.jp g"/> [/img][/url]

It's almost resting on the chainstay is there is no pedalling tension.


 
Posted : 01/09/2017 5:48 pm
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I personally would be happy losing a link or so from that (depending whether it's a hardtail or not) and bringing the mech upwards a little when in the biggest cog.

This photo is from a Pinkbike article that shows it about right imho. Obviously whether or not it's a suspension bike is a factor.

[img] [/img]

[url= https://m.pinkbike.com/news/Tech-Tuesday-Chain-Length-Basics-2012.html ]Pinkbike article[/url]


 
Posted : 01/09/2017 5:56 pm
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I would take a link out without hesitation.


 
Posted : 01/09/2017 6:16 pm
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What about deviation or repetition?


 
Posted : 01/09/2017 7:03 pm
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Unless you think you're likely to go up a chainring size I'd take a link out probably. Or not, it's not that bad.


 
Posted : 01/09/2017 7:25 pm
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yeh too long, surprised it's not rubbing on the mech in the smallest cog (looks like it must be close).


 
Posted : 01/09/2017 7:26 pm
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I would take a link out without deviation. If not sufficient, I would take a link out with repetition.


 
Posted : 01/09/2017 8:34 pm
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Thanks a lot - it's a hardtail.

What's deviation / repetition please ?


 
Posted : 02/09/2017 1:20 am
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Link out & some B screw winding in to stop the noise on the 42. This is of course accepting that the low stop screw is adjusted correctly?

What's deviation / repetition please ?

Someone will give you the answer in just a minute


 
Posted : 02/09/2017 5:57 am
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[url= http://si.shimano.com/#/en/DM/RD0004 ]Shimano tech manual link (I think it's the correct model)[/url]
Break the chain and put it around the large ring/large sprocket, sixty seconds tops, don't hesitate


 
Posted : 02/09/2017 6:35 am
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Can i claim my bonus point that rocketdog has actually used repetition?


 
Posted : 02/09/2017 6:55 am
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Rocketdog gets a bash on the head like this. Or like this.


 
Posted : 02/09/2017 6:59 am
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Update - I removed 6 links in the end to make it more or less instruction compliant (max + 2 links)! It makes rear mech adjustment easier and has improved shifting significantly. Still poor compared to old XT-10 speed of course but at least it kinda works for now.

I basically removed twice the length that the loss of 3 teeth equated to so the chain was too long to start with (thanks LBS...).


 
Posted : 19/09/2017 2:28 pm
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caught my wife 'mirin another dudes chain. Its been frosty since.


 
Posted : 19/09/2017 2:48 pm