7 speed cassette an...
 

[Closed] 7 speed cassette and mech with 8 speed shifter. Can it be done?

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As above really, is the gap between the sprockets the same, such that the 'pull' of the shifter will move the derailleur the right distance?

If so, I guess start indexing with the shifter in 7, and 8 will be a redundant click, with the limit screw stopping the mech dropping the chain off the bottom of the cassette?

Cheers, all advice gratefully received.

Alex


 
Posted : 03/09/2009 10:58 pm
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Yep, that'll work fine.


 
Posted : 03/09/2009 11:11 pm
 Ogg
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Spacing is 0.2mm different from 7 speed to 8 speed by the looks of it
http://www.sheldonbrown.com/k7.html#spacing
so you should only be out by upto 0.6mm in 1st and 7th gear so sounds do-able.
No practical experience though!

Ogg


 
Posted : 03/09/2009 11:13 pm
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what ^ they said (especially Ogg)

make the central sprocket the one that lines up perfectly, not the smallest as you might for perfectly matching shifter


 
Posted : 03/09/2009 11:34 pm
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OK, so index from the middle, and it might get a bit jumpy at the extremes. Ta.

Rolfharris, have you any experience?

Cheers

Alex

PS, Ogg is that you?


 
Posted : 03/09/2009 11:37 pm
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Done it an dyou have to accept a little skip in one gear 4 th in mine but a half click of old STI shifter sorts it
Yes it can be done index is a bit more fidllely (spell?)to get it working OK.


 
Posted : 03/09/2009 11:41 pm
 Ogg
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PS, Ogg is that you?

Yes it is - cheers for the loan of the room last weekend!


 
Posted : 05/09/2009 9:18 am
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No worries, and thanks for the spot-on advice. Gonna see if I can blag a 7 speed unit from the parts bin at the office.

A


 
Posted : 05/09/2009 4:29 pm