can this be used on...
 

[Closed] can this be used on xt crank. problem?

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hi all.just fitted an 09 xt ht2 crank set.
xt 22 and standard deore 36t+bash.
when in 7,8,and 9th the chain catches on the raised forms on the inside of the 36t.
is the width inbetween the ring mounts narower on the xt so the deore cannot be used or am i missing somthing.
cheers gang.


 
Posted : 13/09/2009 11:16 pm
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this is the 36.
http://www.chainreactioncycles.com/Models.aspx?ModelID=5699


 
Posted : 13/09/2009 11:19 pm
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Sounds like a chainline issue, made worse by the larger diameter of the 36t ring, a larger granny to match may help.


 
Posted : 14/09/2009 7:45 am
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Im assuming that this is happening when you're in the granny ring? Also by 7th, 8th and 9th you mean the 3 smallest sprockets?
Perhaps you need to move the RHS cup of the BB out a smidge to stop it catching on the shift tabs on the middle chainring.
If you have 68mm BB width you need 2 spacers on the drive side and 1 on the non drive side.


 
Posted : 14/09/2009 9:00 am
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Why are you using Granny with 7/8/9?

Those ratios will be available on the 36 with better chainline.


 
Posted : 14/09/2009 9:13 am
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bigyinn.yes there are 2x 2.5mm spacers on the drive side
and yes the 3 smallest sprockets.
there was no problem befor i changed the crank from fsa mega gap exo to the xt771.if it is achain line issue how is it resolved??


 
Posted : 14/09/2009 5:52 pm
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bump


 
Posted : 14/09/2009 11:05 pm
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Just don't use those gears - they are duplicated on the middle ring.

Bad chain crossing anyway.


 
Posted : 14/09/2009 11:39 pm
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tj it,s just anoying me.
what do you mean when you say, Bad chain crossing.
cheers


 
Posted : 14/09/2009 11:41 pm
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Look at the angles on the chain when you are in granny 9. the chain is being bent badly - thats chain crossing.

A dérailleur system works best when the chain is as straight as possible.

My bikes are set up so that granny 1-5 and all all nine on the 36 are usable withouut rub. No need for those othere gears as they are duplicated and the chain will be bent and slack


 
Posted : 14/09/2009 11:48 pm
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so basicly just don,t wory about it and forget about granny 6-7-8-9.


 
Posted : 15/09/2009 12:02 am
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Yep, TJ is correct. Just the angles on the chain relative to the chainring is too extreme and catches the shift ramps.
I've got mine (its a triple, but the principles are the same) so that in the granny i can use sprockets 1-4 in the granny and everything else in the middle, although i rarely use the gears at either extremes.


 
Posted : 15/09/2009 8:54 am
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Increases the chance of snapping your chain if you load it hard when it's bent across the rings.


 
Posted : 15/09/2009 12:12 pm
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cheers all. sound advice once again.


 
Posted : 15/09/2009 7:23 pm