Singlespeed & Fixed Gear - Campy bottom bracket/chainline question

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cbieryla
06-07-09, 07:20 AM
Hi,

I am helping a friend source parts for his first fixed gear project. He recently purchased a campy mirage triple crank arm set on the cheap. Having only used Shimano/Sram compatible components thus far, I was unsure which size ISO bottom bracket would be best matched with these cranks to achieve a decent chainline. I realize that he could use spacers in the rear, but I know if it were my bike, I would prefer to not have to go that route, or at least keep the spacers to a minimum. A bit more info...the rear spacing on this bike is 120mm.

p.s. I have already checked to see what Sheldon had to say on the matter, and found very little info as it specifically relates to Campy BB's. If anyone has any info. I would greatly appreciate it.


Bianchigirll
06-07-09, 08:23 AM
WHat year is the crankset? that might make a difference but according to my 1999 Campi catalog the Mirage triple takes a 115.5. if you are not using the inner ring position you might beable to use a shorter one but that may require trial and error.

dookie
06-07-09, 04:43 PM
the Mirage triple takes a 115.5.

yes.


clink83
06-07-09, 06:17 PM
WHat year is the crankset? that might make a difference but according to my 1999 Campi catalog the Mirage triple takes a 115.5. if you are not using the inner ring position you might beable to use a shorter one but that may require trial and error.
You can only use the middle and outer chain rings on a triple to get any meaningful gear ratio. If you use a triple BB you are not going to be able to get anything close to a useable chainline.