campy chainline?

Brian Plaugher said:

After a repaint, I faced the bottom bracket shell on a 2001 Bianchi
Eros. It had not been done before, judging from the previous paint
stuck in a groove on the right side. After my careful work, the
bottom bracket seems to be shifted to the left. Drive side crank
almost bottoms out, while plenty of spindle is showing on the
left. Is it possible my facing removed enough material to shift the
BB significantly to the left? What is the suggested measurement for
the Campy chainline (Veloce triple)? Is there any problem,
aesthetics aside, with a not-quite-symmetrical bottom bracket?

Not possible. Are you sure you haven't reversed the spindle? The
only result from facing the BB is to expose more left hand cup, the
right bearing cup always bottoming on its shoulder, so the left cup
sticks out farther, the spindle being as long as it always was.

Jobst Brandt
[email hidden]

On 10 Jun 2004 12:13:38 -0700, [email hidden] (Brian Plaugher)

Quoted message said:

After a repaint, I faced the bottom bracket shell on a 2001 Bianchi
Eros. It had not been done before, judging from the previous paint
stuck in a groove on the right side.

Trivia: that groove marks the drive side so the frame builder welds
the shell into the frame facing the right way. The shell could have
been faced without getting that paint out, so your frame *might* have
been faced before hand after all.

Quoted message said:

After my careful work, the bottom
bracket seems to be shifted to the left. Drive side crank almost
bottoms out,

On the chain stay? Not on the bb cup, right?

Quoted message said:

while plenty of spindle is showing on the left. Is it
possible my facing removed enough material to shift the BB
significantly to the left?

Not likely, but an overzealous or inexperienced person might get half
a millimeter (if the cutter is sharp).

Quoted message said:

What is the suggested measurement for the
Campy chainline (Veloce triple)?

I think Shimano is 46mm; Campy should be close.

Quoted message said:

Is there any problem, aesthetics
aside, with a not-quite-symmetrical bottom bracket?

Been used for decades.

I think Jobst may have got it right -- if your spindle is asymmetrical
it might be turned around.

It was queried:

Quoted message said:

I think Jobst may have got it right -- if your spindle is asymmetrical
it might be turned around.

This is a cartridge bb, with the fixed cup, well, fixed to the
cartridge, so I don't see how it could be reversed. The crank is not
touching the chainstay, it is simply closer to the bb cup on the
right/drive side than on the left.
If I did in fact remove as much as a millimeter of material from the
bb shell, I suppose an equivalent spacer would reduce the amount it
sticks out on the left, and put the chainline closer to where it is
supposed to be.
Brian Plaugher