Campy Veloce crankset - bottom bracket & q factor
Mike Tsoi
NOS 2006 Campy Veloce compact crank and Campy Chorus 68x102 square
taper bottom bracket and when I installed it, the small chainring
touched the frame. It is obvious now that it was the wrong
combination.
I have a Chorus ultra torque crankset on another bike and the q factor
of 145.5 is perfect for me and I want to match it on this bike. Does
anyone know if I get the Veloce or Centaur bottom bracket of 68x111 if
that will give me the same q factor of 145.5mm?
Does anyone know the difference between the Veloce and Centaur bottom
bracket and which is better?
Thanks in advance for helping out.
Mike
Norman
> I need some help and hoping someone here can help me. I purchased a
> NOS 2006 Campy Veloce compact crank and Campy Chorus 68x102 square
> taper bottom bracket and when I installed it, the small chainring
> touched the frame. It is obvious now that it was the wrong
> combination.
>
> I have a Chorus ultra torque crankset on another bike and the q factor
> of 145.5 is perfect for me and I want to match it on this bike. Does
> anyone know if I get the Veloce or Centaur bottom bracket of 68x111 if
> that will give me the same q factor of 145.5mm?
Without books or the equipment before me, I would
venture a method: draw down on most cranks in
good working order that I have used is between 6 &
1 mm of the end of the tapers inside the cranks.
Measure the relative offsets of the pedal attachment
to a (badly) fudged 4mm of clearance (I ain't gonna
take 'em apart, but my ol' c-records look like about 17
or 18mm) & add that to the spindle length. This would
make my case (with 109mm sugino spindle) 143mm
to 145mm calculated.
An actual measurement gives me 141mm (so it looks
like the actual pedal offset is right at 16mm for my tore
up old c-records) & I was eye-balling from the murky
depths of molto amaretto. I'm sure you can science 35
times better.
>
> Does anyone know the difference between the Veloce and Centaur bottom
> bracket and which is better?
Campagnolo stuff of these levels is all more than good
enough. I have a personal grudge against aluminium
bottom bracket cups (to say nothing of cartridges), ergo
I'd best keep my mouth shut so as no squirrel paste flies
in.
Lou Holtman
With a 111 mm BB it will be 9 mm wider that with the 102 mm. ;-) . Put
the cranks on the 102 mm BB you have got when it not installed and
measure the Q-factor. Then add 9 mm.
Within what margin is the Q factor important to you?
Lou
Qui si parla Campagnolo
Yes. This crank along with non Ultra Torque cranks of Centaur and
Mirage need a ISO symmetrical 111mm BB, like that of Veloce AC-H or
the still made triple bearing Centaur. 'Veloce is Alloy Cup, Hollow
axle. Nice unit with 2 cart bearings. Centaur is much nicer, 3 bearing
design like the 102mm unit you have but longer spindle.
Mike Tsoi
>
> - Show quoted text -
After I sent out this message, I realized that I could install the bb
and crank after taking off the bottom bracket and do the math. Of
course, I haven't gotten around to it yet.
I think the margin has to be within a couple of mm. I have another
bike set up with a q factor of 151mm and after a long ride, my left
knee feels a bit "off". Same pedal system on both.
Mike Tsoi
wrote:
>
> - Show quoted text -
Sorry for being a little slow. So a ISO symmetrical 111mm bottom
bracket will give me a q factor of 145.5mm? If so, then the Centaur
BB it is.
Mike Tsoi
>
> - Show quoted text -
Thanks for the replies. I took off the Chorus bottom bracket and
installed the crankset. The q factor is 141mm so if I put the right
bottom bracket of 111mm, the q factor would be 152mm. This doesn't
work well for me so I'm going to get a Centaur UT which gives me the
same q factor as my Chorus (145.5mm)
Hank
>
> - Show quoted text -
You're sensitive to 6.5 mm of Q? I have that much difference between
pairs of shoes.
Are your shoes slid all the way in on your cleats?
Mike Tsoi
>
> - Show quoted text -
Apparently I am that sensitive. Used the same shoes and the pedals
are either Dura Ace or Ultegra from the same design year. On my
Chorus setup, I've done 200 milers and no knee issues. On the wider
cranks (151mm), I get knee twinges after 50 miles or so. Since I'm
trying to set this bike up for brevets, I need to have the same q
factor as the Chorus. I wish q factor wasn't an issue for me. It
would be much cheaper that way.
AMuzi
You meant 45mm chainline right?
Use ACH/Vel or Cen 111 spindle (115 with fat frame tubes)
Centaur is a higher quality bearing system but ccsts more.
Both work fine.
--
Andrew Muzi
<www.yellowjersey.org/>
Open every day since 1 April, 1971