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Shimano bb
 

[Closed] Shimano bb

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[#4608215]

Just went on to hollowtech 2 bb for the first time and ive put 2 washers drive side and 1 washer the other but my mech wont go over enough to change to the outer ring should i change washers roung


 
Posted : 29/11/2012 10:47 pm
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yes


 
Posted : 29/11/2012 10:48 pm
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what size BB shell do you have.


 
Posted : 29/11/2012 10:48 pm
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How wide is your BB shell? If it's 73mm, you only need the one (Drive Side) washer.


 
Posted : 29/11/2012 10:48 pm
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nope it 68mm


 
Posted : 29/11/2012 10:50 pm
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Hmm wondering if mine's right

http://singletrackworld.com/forum/topic/68mm-bb-and-ht2-bb-spacers


 
Posted : 29/11/2012 10:53 pm
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Assuming you've adjusted the limit screws and set the cable tension correctly, it may be that you have an old mech designed for a narrower chainline. It may be possible to bodge it by swapping BB spacers, but a newer mech may be required.


 
Posted : 30/11/2012 9:15 am
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Weirdly, my latest HT2 BB came with different sized spacers to the last one - one very thin one instead of one of the 2.5mm spacers. I just used the old ones, and it seems to work fine.

Anyone know if I should have done something different?


 
Posted : 30/11/2012 9:22 am
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No I've got new xt top swing mech


 
Posted : 30/11/2012 1:10 pm
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Andy,

Please specify the model numbers for the crankset and front mech, as well as ring sizes.

PaulD


 
Posted : 30/11/2012 1:13 pm
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Xt m770 front mech top swing
Xt crank set


 
Posted : 30/11/2012 1:54 pm
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Xt m770 front mech top swing
Xt crank set rings are all 2.5 x 3


 
Posted : 30/11/2012 1:55 pm
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Andy,

I was not specific enough, but what chainring sizes?

M770 front mech should be OK for a triple 44-32-22 and be fine for your crankset with the 2+1 spacers on a 68mm shell.

Check the mech limit screws and the shifter cable slack.

PaulD


 
Posted : 30/11/2012 3:19 pm
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Yeah I've checked lot
Screw and try pushing mech over won't go any further


 
Posted : 30/11/2012 4:48 pm
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any suggestions then


 
Posted : 01/12/2012 6:39 pm