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Would it be possible to change a tripple to a double by removing the granny ring, changing the bottom bracket (to a double) and readjusting the front derailure?
Will the shifting be as precise as a true double: crank, bb and derailure?
 

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Banned forever.....or not
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Very close.
 

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NeoRetroGrouch
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Might hit the chainstay....

Even without the granny ring, the inner spider might hit your chainstay if you move it in that far.
TF
 

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close, but no cigar...

Depending on what model of crank you have now, it may be difficult to find the proper spindle length. The typical difference in spindle length between the current Shimnao double and triple spindles is 9mm. Only about 6mm is required to get the proper chainline. If nothing hits the frame you may be OK, but the cranks may also be too close to the seat tube to allow proper adjustment of the front derailleur.

Also, if you really want the function of a double, a double front derailleur should be installed. The narrower front derailleur will shift better and not require as much trimming as the wider triple derailleur.

If you buy a bottom bracket that will fit the double crank that you should have, then the worst case is you'll have to bite the bullet and get the crank if the modified triple doesn't perform as desired.
 

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what triple?

Slip Stream said:
Would it be possible to change a tripple to a double by removing the granny ring, changing the bottom bracket (to a double) and readjusting the front derailure?
Will the shifting be as precise as a true double: crank, bb and derailure?
Might depend on which triple it is. Dura Ace has the granny attach to little tabs on a special middle ring, not directly to the spider. Ultegra and Campy triples attach the granny to the spider itself. I'm not sure either way, but it could make a difference.

You might have some chain line and derailleur alignment issues.

Doug
 
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