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clweed
11-17-2011, 05:35 PM
I have a chorus triple mounted to a 111 mm spindle. I know the chainline is supposed to be 45 but I'm getting 48mm.

I checked the spindle length and the crank arms are bottomed out tight to the spindle.

Any thoughts on the cause or don't worry about it.

Thanks,

Lee
Mike748
11-17-2011, 05:44 PM
are you using the 3mm offset bb or symmetric 111? chorus should use the offset but that would only make your situation worse if you have symmetric now...

and you are measuring centerline to middle ring?
pavel
11-17-2011, 05:49 PM
I think you might need the 115 for chorus?
clweed
11-17-2011, 05:49 PM
Mike,

Symmetric, center of 28.6 DT to center chainring. I can't figure it out.

Lee
clweed
11-17-2011, 05:51 PM
I think you might need the 115 for chorus?

Wouldn't that make it worse? A 111 is measuring 48
chismog
11-17-2011, 05:59 PM
chorus and record triple require a 111 asymmetrical BB. If you're using the ac-h or centaur, or old record/chorus from the 80s, that is 111 symmetrical BB. I think this may be your problem.

C
Dave
11-17-2011, 06:05 PM
A Chorus crank needs the asymetric BB. The correct chainline is 46.5mm.

Whether an asymteric BB would make the chainline better or worse, depends on the direction of the offset. I've never had one to know if it increases or decreases the chainline.

You need a precison rule to meaure the chainline, from the side of the seat tube to the tip of a tooth on the middle ring. Add half the seat tube diameter to get the total amount. Don't try to eyeball the center of the seat tube.

http://www.campagnolo.com/repository/documenti/en/7225254_Crankset-07-05.pdf
oldpotatoe
11-17-2011, 06:07 PM
Mike,

Symmetric, center of 28.6 DT to center chainring. I can't figure it out.

Lee

Wrong BB.
clweed
11-17-2011, 06:17 PM
Wrong BB.

I'm assuming the the longer side of the spindle would be on the drive side, correct?
pavel
11-17-2011, 06:18 PM
Wouldn't that make it worse? A 111 is measuring 48

sorry - you're right.
oldpotatoe
11-17-2011, 06:18 PM
I'm assuming the the longer side of the spindle would be on the drive side, correct?


Correct. Dry spindle torque to-I use 30 ft-lbs.
clweed
11-18-2011, 08:34 AM
Correct. Dry spindle torque to-I use 30 ft-lbs.

I double checked the BB and it is asymmetrical, dry spindle torqued to 30 ft-lbs yields 47.3mm.
Do you think that is close enough or should I try a different BB ?

Thanks for the replies,

Lee
oldpotatoe
11-18-2011, 09:32 AM
I double checked the BB and it is asymmetrical, dry spindle torqued to 30 ft-lbs yields 47.3mm.
Do you think that is close enough or should I try a different BB ?

Thanks for the replies,

Lee

Hows the small ring to RH chainstay clearance?

Hows the FD action, to all 3 rings?

How's the chainline look, middle of crankset to middle of cogset, that line in relation to the top tube?

If these are OK, I wouldn't fret about 2.5 some mms.
Chance
11-18-2011, 09:45 AM
I double checked the BB and it is asymmetrical, dry spindle torqued to 30 ft-lbs yields 47.3mm.
Do you think that is close enough or should I try a different BB ?

Thanks for the replies,

Lee
If Dave is right about 46.5 mm being the spec then you are within 1 mm. How much closer does it need to be?
clweed
11-18-2011, 09:55 AM
If Dave is right about 46.5 mm being the spec then you are within 1 mm. How much closer does it need to be?

Yes Dave is correct as always, it is 46.5 I'm calling it good.

thanks everyone

Lee