Help wanted on bike build

[neily42]

Hi all im new here so a big HELLO. I've got an old claud butler which ive just had powder coated. It was a 21 speed but ive changed it all to a 27 speed. I have changes every thing to so this ie rear derailleur cassette

 

[neily42]

Ok im closer to finding out what my problem is here. My bottom bracket was indeed the wrong size, so I've bought the correct one and fitted it BUT now its fitted I still can't get the chainset to get samllest gear on the chainset what is going on here. Is it my octalink chainset is it my front derailleur. When you look down the chain there is no way the derailleur is going to shift the chain onto the bottom gear, its a deore front derailleur brand new, have I got my calculations wrong with mu set up any help appreciated thanks

 

[RunBikeDog]

It might be a 2x9 rather than a 3x9 front derailuer...in which case it won't shift intot he smallest front gear.

 

[alfeng]

Originally Posted by neily42 .

Ok im closer to finding out what my problem is here. My bottom bracket was indeed the wrong size, so I've bought the correct one and fitted it BUT now its fitted I still can't get the chainset to get samllest gear on the chainset what is going on here. Is it my octalink chainset is it my front derailleur. When you look down the chain there is no way the derailleur is going to shift the chain onto the bottom gear, its a deore front derailleur brand new, have I got my calculations wrong with mu set up any help appreciated thanks

It sounds as though you have the wrong length BB spindle ...

If you have a Dura Ace, Ultegra, or 105 ROAD crank, then the BB which Shimano wants you to use is the one with the Octalkink BB with a 118mm spindle ...

BUT, 'I' found that I could use a 112.5mm XTR Octalink BB with an Ultegra 6503 Triple crankset ...

To state the obvious, the 109.5mm V1 Octalink BB won't work with a Triple.

If you have a Tiagra crankset which has a V2 Octalink BB (the one which XT/LX cranks also use), then the 113mm BB is obviously too short & you will have to get the next size up.